diff --git a/Makefile b/Makefile
index 7c055ffae..8d13b9890 100644
--- a/Makefile
+++ b/Makefile
@@ -48,6 +48,9 @@ styles:
 	@lessc -x searx/static/themes/default/less/style.less > searx/static/themes/default/css/style.css
 	@lessc -x searx/static/themes/courgette/less/style.less > searx/static/themes/courgette/css/style.css
 	@lessc -x searx/static/less/bootstrap/bootstrap.less > searx/static/css/bootstrap.min.css
+	@lessc -x searx/static/less/bootstrap/bootstrap_simplex.less > searx/static/css/bootstrap.simplex.min.css
+	@lessc -x searx/static/less/bootstrap/bootstrap_yeti.less > searx/static/css/bootstrap.yeti.min.css
+	@lessc -x searx/static/less/bootstrap/bootstrap_readable.less > searx/static/css/bootstrap.readable.min.css
 	@lessc -x searx/static/themes/oscar/less/oscar/oscar.less > searx/static/themes/oscar/css/oscar.min.css
 
 grunt:
diff --git a/searx/static/css/bootstrap.min.css b/searx/static/css/bootstrap.min.css
index fb0e84ae4..691604be6 100644
Binary files a/searx/static/css/bootstrap.min.css and b/searx/static/css/bootstrap.min.css differ
diff --git a/searx/static/css/bootstrap.readable.min.css b/searx/static/css/bootstrap.readable.min.css
new file mode 100644
index 000000000..41fd654a8
Binary files /dev/null and b/searx/static/css/bootstrap.readable.min.css differ
diff --git a/searx/static/css/bootstrap.simplex.min.css b/searx/static/css/bootstrap.simplex.min.css
new file mode 100644
index 000000000..2a34b36ff
Binary files /dev/null and b/searx/static/css/bootstrap.simplex.min.css differ
diff --git a/searx/static/css/bootstrap.yeti.min.css b/searx/static/css/bootstrap.yeti.min.css
new file mode 100644
index 000000000..e98a99e62
Binary files /dev/null and b/searx/static/css/bootstrap.yeti.min.css differ
diff --git a/searx/static/less/bootstrap/bootstrap_readable.less b/searx/static/less/bootstrap/bootstrap_readable.less
new file mode 100644
index 000000000..cb504f3e3
--- /dev/null
+++ b/searx/static/less/bootstrap/bootstrap_readable.less
@@ -0,0 +1,55 @@
+// Core variables and mixins
+@import "variables.less";
+@import "theme_readable/variables.less";
+@import "mixins.less";
+
+// Reset and dependencies
+@import "normalize.less";
+@import "print.less";
+@import "glyphicons.less";
+
+// Core CSS
+@import "scaffolding.less";
+@import "type.less";
+@import "code.less";
+@import "grid.less";
+@import "tables.less";
+@import "forms.less";
+@import "buttons.less";
+
+// Components
+@import "component-animations.less";
+@import "dropdowns.less";
+@import "button-groups.less";
+@import "input-groups.less";
+@import "navs.less";
+@import "navbar.less";
+@import "breadcrumbs.less";
+@import "pagination.less";
+@import "pager.less";
+@import "labels.less";
+@import "badges.less";
+@import "jumbotron.less";
+@import "thumbnails.less";
+@import "alerts.less";
+@import "progress-bars.less";
+@import "media.less";
+@import "list-group.less";
+@import "panels.less";
+@import "responsive-embed.less";
+@import "wells.less";
+@import "close.less";
+
+// Components w/ JavaScript
+@import "modals.less";
+@import "tooltip.less";
+@import "popovers.less";
+@import "carousel.less";
+
+// Utility classes
+@import "utilities.less";
+@import "responsive-utilities.less";
+
+// own additions
+@import "typeahead.less";
+@import "theme_readable/bootswatch.less";
diff --git a/searx/static/less/bootstrap/bootstrap_simplex.less b/searx/static/less/bootstrap/bootstrap_simplex.less
new file mode 100644
index 000000000..4390b668d
--- /dev/null
+++ b/searx/static/less/bootstrap/bootstrap_simplex.less
@@ -0,0 +1,55 @@
+// Core variables and mixins
+@import "variables.less";
+@import "theme_simplex/variables.less";
+@import "mixins.less";
+
+// Reset and dependencies
+@import "normalize.less";
+@import "print.less";
+@import "glyphicons.less";
+
+// Core CSS
+@import "scaffolding.less";
+@import "type.less";
+@import "code.less";
+@import "grid.less";
+@import "tables.less";
+@import "forms.less";
+@import "buttons.less";
+
+// Components
+@import "component-animations.less";
+@import "dropdowns.less";
+@import "button-groups.less";
+@import "input-groups.less";
+@import "navs.less";
+@import "navbar.less";
+@import "breadcrumbs.less";
+@import "pagination.less";
+@import "pager.less";
+@import "labels.less";
+@import "badges.less";
+@import "jumbotron.less";
+@import "thumbnails.less";
+@import "alerts.less";
+@import "progress-bars.less";
+@import "media.less";
+@import "list-group.less";
+@import "panels.less";
+@import "responsive-embed.less";
+@import "wells.less";
+@import "close.less";
+
+// Components w/ JavaScript
+@import "modals.less";
+@import "tooltip.less";
+@import "popovers.less";
+@import "carousel.less";
+
+// Utility classes
+@import "utilities.less";
+@import "responsive-utilities.less";
+
+// own additions
+@import "typeahead.less";
+@import "theme_simplex/bootswatch.less";
diff --git a/searx/static/less/bootstrap/bootstrap_yeti.less b/searx/static/less/bootstrap/bootstrap_yeti.less
new file mode 100644
index 000000000..1fe014cd2
--- /dev/null
+++ b/searx/static/less/bootstrap/bootstrap_yeti.less
@@ -0,0 +1,55 @@
+// Core variables and mixins
+@import "variables.less";
+@import "theme_yeti/variables.less";
+@import "mixins.less";
+
+// Reset and dependencies
+@import "normalize.less";
+@import "print.less";
+@import "glyphicons.less";
+
+// Core CSS
+@import "scaffolding.less";
+@import "type.less";
+@import "code.less";
+@import "grid.less";
+@import "tables.less";
+@import "forms.less";
+@import "buttons.less";
+
+// Components
+@import "component-animations.less";
+@import "dropdowns.less";
+@import "button-groups.less";
+@import "input-groups.less";
+@import "navs.less";
+@import "navbar.less";
+@import "breadcrumbs.less";
+@import "pagination.less";
+@import "pager.less";
+@import "labels.less";
+@import "badges.less";
+@import "jumbotron.less";
+@import "thumbnails.less";
+@import "alerts.less";
+@import "progress-bars.less";
+@import "media.less";
+@import "list-group.less";
+@import "panels.less";
+@import "responsive-embed.less";
+@import "wells.less";
+@import "close.less";
+
+// Components w/ JavaScript
+@import "modals.less";
+@import "tooltip.less";
+@import "popovers.less";
+@import "carousel.less";
+
+// Utility classes
+@import "utilities.less";
+@import "responsive-utilities.less";
+
+// own additions
+@import "typeahead.less";
+@import "theme_yeti/bootswatch.less";
diff --git a/searx/static/less/bootstrap/theme_readable/bootswatch.less b/searx/static/less/bootstrap/theme_readable/bootswatch.less
new file mode 100644
index 000000000..6404ff231
--- /dev/null
+++ b/searx/static/less/bootstrap/theme_readable/bootswatch.less
@@ -0,0 +1,187 @@
+// Readable 3.3.1
+// Bootswatch
+// -----------------------------------------------------
+
+@import url("//fonts.googleapis.com/css?family=Raleway:400,700");
+
+// Navbar =====================================================================
+
+.navbar {
+  font-family: @headings-font-family;
+
+  &-nav,
+  &-form {
+    margin-left: 0;
+    margin-right: 0;
+  }
+
+  &-nav > li > a {
+    padding: @padding-base-vertical @padding-base-horizontal;
+    margin: 12px 6px;
+    border: 1px solid transparent;
+    border-radius: @border-radius-base;
+
+    &:hover {
+      border: 1px solid #ddd;
+    }
+  }
+
+  &-nav > .active > a,
+  &-nav > .active > a:hover {
+    border: 1px solid #ddd;
+  }
+
+  &-default .navbar-nav > .active > a:hover {
+    color: @navbar-default-link-hover-color;
+  }
+
+  &-inverse .navbar-nav > .active > a:hover {
+    color: @navbar-inverse-link-hover-color;
+  }
+
+  &-brand {
+    padding-top: 20px;
+  }
+}
+
+@media (max-width: @grid-float-breakpoint) {
+  .navbar {
+    .navbar-nav > li > a {
+      margin: 0;
+    }
+  }
+}
+
+// Buttons ====================================================================
+
+.btn {
+  font-family: @headings-font-family;
+}
+
+// Typography =================================================================
+
+// Tables =====================================================================
+
+// Forms ======================================================================
+
+legend {
+  font-family: @headings-font-family;
+}
+
+.input-group-addon {
+  font-family: @font-family-sans-serif;
+}
+
+// Navs =======================================================================
+
+.nav {
+  .open > a,
+  .open > a:hover,
+  .open > a:focus {
+    border: 1px solid #ddd;
+  }
+}
+
+.pagination {
+
+  font-family: @headings-font-family;
+
+  &-lg > li > a,
+  &-lg > li > span {
+    padding: 14px 24px;
+  }
+}
+
+.pager {
+
+  font-family: @headings-font-family;
+
+  a {
+    color: @text-color;
+  }
+
+  a:hover {
+    border-color: transparent;
+    color: #fff;
+  }
+
+  .disabled a {
+    border-color: @pager-border;
+  }
+}
+
+// Indicators =================================================================
+
+.close {
+  color: #fff;
+  text-decoration: none;
+  text-shadow: none;
+  opacity: 0.4;
+
+  &:hover,
+  &:focus {
+    color: #fff;
+    opacity: 1;
+  }
+}
+
+.alert {
+  .alert-link {
+    color: @alert-success-text;
+    text-decoration: underline;
+  }
+}
+
+.label {
+  font-family: @headings-font-family;
+  font-weight: normal;
+
+  &-default {
+    border: 1px solid #ddd;
+    color: @text-color;
+  }
+
+}
+
+.badge {
+  padding: 1px 7px 5px;
+  vertical-align: 2px;
+  font-family: @headings-font-family;
+  font-weight: normal;
+}
+
+// Progress bars ==============================================================
+
+// Containers =================================================================
+
+.panel {
+  .box-shadow(none);
+
+  &-default {
+    .close {
+      color: @text-color;
+    }
+  }
+
+  &-primary,
+  &-success,
+  &-warning,
+  &-danger,
+  &-info {
+    .panel-heading {
+      color: #fff;
+    }
+
+    .panel-body {
+      border: 1px solid #ddd;
+      border-top-width: 0;
+      border-radius: 0 0 @border-radius-base @border-radius-base;
+    }
+  }
+}
+
+.modal {
+  .close {
+    color: @text-color;
+  }
+}
diff --git a/searx/static/less/bootstrap/theme_readable/variables.less b/searx/static/less/bootstrap/theme_readable/variables.less
new file mode 100644
index 000000000..071cdec93
--- /dev/null
+++ b/searx/static/less/bootstrap/theme_readable/variables.less
@@ -0,0 +1,856 @@
+// Readable 3.3.1
+// Variables
+// --------------------------------------------------
+
+
+//== Colors
+//
+//## Gray and brand colors for use across Bootstrap.
+
+@gray-base:              #000;
+@gray-darker:            lighten(@gray-base, 13.5%); // #222
+@gray-dark:              lighten(@gray-base, 20%);   // #333
+@gray:                   lighten(@gray-base, 33.5%); // #555
+@gray-light:             lighten(@gray-base, 70%);   // #999
+@gray-lighter:           lighten(@gray-base, 93.5%); // #eee
+
+@brand-primary:         #4582EC;
+@brand-success:         #3FAD46;
+@brand-info:            #5bc0de;
+@brand-warning:         #f0ad4e;
+@brand-danger:          #d9534f;
+
+
+//== Scaffolding
+//
+//## Settings for some of the most global styles.
+
+//** Background color for `<body>`.
+@body-bg:               #fff;
+//** Global text color on `<body>`.
+@text-color:            @gray-dark;
+
+//** Global textual link color.
+@link-color:            @brand-primary;
+//** Link hover color set via `darken()` function.
+@link-hover-color:      darken(@link-color, 20%);
+//** Link hover decoration.
+@link-hover-decoration: underline;
+
+
+//== Typography
+//
+//## Font, line-height, and color for body text, headings, and more.
+
+@font-family-sans-serif:  "Raleway", "Helvetica Neue", Helvetica, Arial, sans-serif;
+@font-family-serif:       Georgia, "Times New Roman", Times, serif;
+//** Default monospace fonts for `<code>`, `<kbd>`, and `<pre>`.
+@font-family-monospace:   Menlo, Monaco, Consolas, "Courier New", monospace;
+@font-family-base:        @font-family-serif;
+
+@font-size-base:          16px;
+@font-size-large:         ceil((@font-size-base * 1.25)); // ~18px
+@font-size-small:         ceil((@font-size-base * 0.85)); // ~12px
+
+@font-size-h1:            floor((@font-size-base * 2.6)); // ~36px
+@font-size-h2:            floor((@font-size-base * 2.15)); // ~30px
+@font-size-h3:            ceil((@font-size-base * 1.7)); // ~24px
+@font-size-h4:            ceil((@font-size-base * 1.25)); // ~18px
+@font-size-h5:            @font-size-base;
+@font-size-h6:            ceil((@font-size-base * 0.85)); // ~12px
+
+//** Unit-less `line-height` for use in components like buttons.
+@line-height-base:        1.428571429; // 20/14
+//** Computed "line-height" (`font-size` * `line-height`) for use with `margin`, `padding`, etc.
+@line-height-computed:    floor((@font-size-base * @line-height-base)); // ~20px
+
+//** By default, this inherits from the `<body>`.
+@headings-font-family:    @font-family-sans-serif;
+@headings-font-weight:    bold;
+@headings-line-height:    1.1;
+@headings-color:          inherit;
+
+
+//== Iconography
+//
+//## Specify custom location and filename of the included Glyphicons icon font. Useful for those including Bootstrap via Bower.
+
+//** Load fonts from this directory.
+@icon-font-path:          "../fonts/";
+//** File name for all font files.
+@icon-font-name:          "glyphicons-halflings-regular";
+//** Element ID within SVG icon file.
+@icon-font-svg-id:        "glyphicons_halflingsregular";
+
+
+//== Components
+//
+//## Define common padding and border radius sizes and more. Values based on 14px text and 1.428 line-height (~20px to start).
+
+@padding-base-vertical:     8px;
+@padding-base-horizontal:   12px;
+
+@padding-large-vertical:    14px;
+@padding-large-horizontal:  16px;
+
+@padding-small-vertical:    5px;
+@padding-small-horizontal:  10px;
+
+@padding-xs-vertical:       1px;
+@padding-xs-horizontal:     5px;
+
+@line-height-large:         1.33;
+@line-height-small:         1.5;
+
+@border-radius-base:        4px;
+@border-radius-large:       6px;
+@border-radius-small:       3px;
+
+//** Global color for active items (e.g., navs or dropdowns).
+@component-active-color:    #fff;
+//** Global background color for active items (e.g., navs or dropdowns).
+@component-active-bg:       @brand-primary;
+
+//** Width of the `border` for generating carets that indicator dropdowns.
+@caret-width-base:          4px;
+//** Carets increase slightly in size for larger components.
+@caret-width-large:         5px;
+
+
+//== Tables
+//
+//## Customizes the `.table` component with basic values, each used across all table variations.
+
+//** Padding for `<th>`s and `<td>`s.
+@table-cell-padding:            8px;
+//** Padding for cells in `.table-condensed`.
+@table-condensed-cell-padding:  5px;
+
+//** Default background color used for all tables.
+@table-bg:                      transparent;
+//** Background color used for `.table-striped`.
+@table-bg-accent:               #f9f9f9;
+//** Background color used for `.table-hover`.
+@table-bg-hover:                #f5f5f5;
+@table-bg-active:               @table-bg-hover;
+
+//** Border color for table and cell borders.
+@table-border-color:            #ddd;
+
+
+//== Buttons
+//
+//## For each of Bootstrap's buttons, define text, background and border color.
+
+@btn-font-weight:                normal;
+
+@btn-default-color:              @text-color;
+@btn-default-bg:                 #fff;
+@btn-default-border:             #ddd;
+
+@btn-primary-color:              #fff;
+@btn-primary-bg:                 @brand-primary;
+@btn-primary-border:             @btn-primary-bg;
+
+@btn-success-color:              #fff;
+@btn-success-bg:                 @brand-success;
+@btn-success-border:             @btn-success-bg;
+
+@btn-info-color:                 #fff;
+@btn-info-bg:                    @brand-info;
+@btn-info-border:                @btn-info-bg;
+
+@btn-warning-color:              #fff;
+@btn-warning-bg:                 @brand-warning;
+@btn-warning-border:             @btn-warning-bg;
+
+@btn-danger-color:               #fff;
+@btn-danger-bg:                  @brand-danger;
+@btn-danger-border:              @btn-danger-bg;
+
+@btn-link-disabled-color:        @gray-light;
+
+
+//== Forms
+//
+//##
+
+//** `<input>` background color
+@input-bg:                       #fff;
+//** `<input disabled>` background color
+@input-bg-disabled:              @gray-lighter;
+
+//** Text color for `<input>`s
+@input-color:                    @text-color;
+//** `<input>` border color
+@input-border:                   #ddd;
+
+// TODO: Rename `@input-border-radius` to `@input-border-radius-base` in v4
+//** Default `.form-control` border radius
+@input-border-radius:            @border-radius-base;
+//** Large `.form-control` border radius
+@input-border-radius-large:      @border-radius-large;
+//** Small `.form-control` border radius
+@input-border-radius-small:      @border-radius-small;
+
+//** Border color for inputs on focus
+@input-border-focus:             #66afe9;
+
+//** Placeholder text color
+@input-color-placeholder:        @gray-light;
+
+//** Default `.form-control` height
+@input-height-base:              (@line-height-computed + (@padding-base-vertical * 2) + 2);
+//** Large `.form-control` height
+@input-height-large:             (ceil(@font-size-large * @line-height-large) + (@padding-large-vertical * 2) + 2);
+//** Small `.form-control` height
+@input-height-small:             (floor(@font-size-small * @line-height-small) + (@padding-small-vertical * 2) + 2);
+
+@legend-color:                   @text-color;
+@legend-border-color:            #e5e5e5;
+
+//** Background color for textual input addons
+@input-group-addon-bg:           @gray-lighter;
+//** Border color for textual input addons
+@input-group-addon-border-color: @input-border;
+
+//** Disabled cursor for form controls and buttons.
+@cursor-disabled:                not-allowed;
+
+
+//== Dropdowns
+//
+//## Dropdown menu container and contents.
+
+//** Background for the dropdown menu.
+@dropdown-bg:                    #fff;
+//** Dropdown menu `border-color`.
+@dropdown-border:                rgba(0,0,0,.15);
+//** Dropdown menu `border-color` **for IE8**.
+@dropdown-fallback-border:       #ccc;
+//** Divider color for between dropdown items.
+@dropdown-divider-bg:            #e5e5e5;
+
+//** Dropdown link text color.
+@dropdown-link-color:            @gray-dark;
+//** Hover color for dropdown links.
+@dropdown-link-hover-color:      #fff;
+//** Hover background for dropdown links.
+@dropdown-link-hover-bg:         @component-active-bg;
+
+//** Active dropdown menu item text color.
+@dropdown-link-active-color:     #fff;
+//** Active dropdown menu item background color.
+@dropdown-link-active-bg:        @component-active-bg;
+
+//** Disabled dropdown menu item background color.
+@dropdown-link-disabled-color:   @gray-light;
+
+//** Text color for headers within dropdown menus.
+@dropdown-header-color:          @gray-light;
+
+//** Deprecated `@dropdown-caret-color` as of v3.1.0
+@dropdown-caret-color:           #000;
+
+
+//-- Z-index master list
+//
+// Warning: Avoid customizing these values. They're used for a bird's eye view
+// of components dependent on the z-axis and are designed to all work together.
+//
+// Note: These variables are not generated into the Customizer.
+
+@zindex-navbar:            1000;
+@zindex-dropdown:          1000;
+@zindex-popover:           1060;
+@zindex-tooltip:           1070;
+@zindex-navbar-fixed:      1030;
+@zindex-modal:             1040;
+
+
+//== Media queries breakpoints
+//
+//## Define the breakpoints at which your layout will change, adapting to different screen sizes.
+
+// Extra small screen / phone
+//** Deprecated `@screen-xs` as of v3.0.1
+@screen-xs:                  480px;
+//** Deprecated `@screen-xs-min` as of v3.2.0
+@screen-xs-min:              @screen-xs;
+//** Deprecated `@screen-phone` as of v3.0.1
+@screen-phone:               @screen-xs-min;
+
+// Small screen / tablet
+//** Deprecated `@screen-sm` as of v3.0.1
+@screen-sm:                  768px;
+@screen-sm-min:              @screen-sm;
+//** Deprecated `@screen-tablet` as of v3.0.1
+@screen-tablet:              @screen-sm-min;
+
+// Medium screen / desktop
+//** Deprecated `@screen-md` as of v3.0.1
+@screen-md:                  992px;
+@screen-md-min:              @screen-md;
+//** Deprecated `@screen-desktop` as of v3.0.1
+@screen-desktop:             @screen-md-min;
+
+// Large screen / wide desktop
+//** Deprecated `@screen-lg` as of v3.0.1
+@screen-lg:                  1200px;
+@screen-lg-min:              @screen-lg;
+//** Deprecated `@screen-lg-desktop` as of v3.0.1
+@screen-lg-desktop:          @screen-lg-min;
+
+// So media queries don't overlap when required, provide a maximum
+@screen-xs-max:              (@screen-sm-min - 1);
+@screen-sm-max:              (@screen-md-min - 1);
+@screen-md-max:              (@screen-lg-min - 1);
+
+
+//== Grid system
+//
+//## Define your custom responsive grid.
+
+//** Number of columns in the grid.
+@grid-columns:              12;
+//** Padding between columns. Gets divided in half for the left and right.
+@grid-gutter-width:         30px;
+// Navbar collapse
+//** Point at which the navbar becomes uncollapsed.
+@grid-float-breakpoint:     @screen-sm-min;
+//** Point at which the navbar begins collapsing.
+@grid-float-breakpoint-max: (@grid-float-breakpoint - 1);
+
+
+//== Container sizes
+//
+//## Define the maximum width of `.container` for different screen sizes.
+
+// Small screen / tablet
+@container-tablet:             (720px + @grid-gutter-width);
+//** For `@screen-sm-min` and up.
+@container-sm:                 @container-tablet;
+
+// Medium screen / desktop
+@container-desktop:            (940px + @grid-gutter-width);
+//** For `@screen-md-min` and up.
+@container-md:                 @container-desktop;
+
+// Large screen / wide desktop
+@container-large-desktop:      (1140px + @grid-gutter-width);
+//** For `@screen-lg-min` and up.
+@container-lg:                 @container-large-desktop;
+
+
+//== Navbar
+//
+//##
+
+// Basics of a navbar
+@navbar-height:                    65px;
+@navbar-margin-bottom:             @line-height-computed;
+@navbar-border-radius:             @border-radius-base;
+@navbar-padding-horizontal:        floor((@grid-gutter-width / 2));
+@navbar-padding-vertical:          ((@navbar-height - @line-height-computed) / 2);
+@navbar-collapse-max-height:       340px;
+
+@navbar-default-color:             @text-color;
+@navbar-default-bg:                @body-bg;
+@navbar-default-border:            #ddd;
+
+// Navbar links
+@navbar-default-link-color:                @link-color;
+@navbar-default-link-hover-color:          @link-color;
+@navbar-default-link-hover-bg:             transparent;
+@navbar-default-link-active-color:         @navbar-default-link-color;
+@navbar-default-link-active-bg:            transparent;
+@navbar-default-link-disabled-color:       #333;
+@navbar-default-link-disabled-bg:          transparent;
+
+// Navbar brand label
+@navbar-default-brand-color:               @navbar-default-link-color;
+@navbar-default-brand-hover-color:         @navbar-default-link-hover-color;
+@navbar-default-brand-hover-bg:            transparent;
+
+// Navbar toggle
+@navbar-default-toggle-hover-bg:           #ddd;
+@navbar-default-toggle-icon-bar-bg:        #ccc;
+@navbar-default-toggle-border-color:       #ddd;
+
+
+// Inverted navbar
+// Reset inverted navbar basics
+@navbar-inverse-color:                      @text-color;
+@navbar-inverse-bg:                         @body-bg;
+@navbar-inverse-border:                     #ddd;
+
+// Inverted navbar links
+@navbar-inverse-link-color:                 @text-color;
+@navbar-inverse-link-hover-color:           @text-color;
+@navbar-inverse-link-hover-bg:              transparent;
+@navbar-inverse-link-active-color:          @text-color;
+@navbar-inverse-link-active-bg:             transparent;
+@navbar-inverse-link-disabled-color:        #ccc;
+@navbar-inverse-link-disabled-bg:           transparent;
+
+// Inverted navbar brand label
+@navbar-inverse-brand-color:                @navbar-inverse-link-color;
+@navbar-inverse-brand-hover-color:          @navbar-inverse-link-hover-color;
+@navbar-inverse-brand-hover-bg:             transparent;
+
+// Inverted navbar toggle
+@navbar-inverse-toggle-hover-bg:            #ddd;
+@navbar-inverse-toggle-icon-bar-bg:         #ccc;
+@navbar-inverse-toggle-border-color:        #ddd;
+
+
+//== Navs
+//
+//##
+
+//=== Shared nav styles
+@nav-link-padding:                          10px 15px;
+@nav-link-hover-bg:                         @gray-lighter;
+
+@nav-disabled-link-color:                   @gray-light;
+@nav-disabled-link-hover-color:             @gray-light;
+
+//== Tabs
+@nav-tabs-border-color:                     #ddd;
+
+@nav-tabs-link-hover-border-color:          @gray-lighter;
+
+@nav-tabs-active-link-hover-bg:             @body-bg;
+@nav-tabs-active-link-hover-color:          @gray;
+@nav-tabs-active-link-hover-border-color:   #ddd;
+
+@nav-tabs-justified-link-border-color:            #ddd;
+@nav-tabs-justified-active-link-border-color:     @body-bg;
+
+//== Pills
+@nav-pills-border-radius:                   @border-radius-base;
+@nav-pills-active-link-hover-bg:            @component-active-bg;
+@nav-pills-active-link-hover-color:         @component-active-color;
+
+
+//== Pagination
+//
+//##
+
+@pagination-color:                     @text-color;
+@pagination-bg:                        #fff;
+@pagination-border:                    #ddd;
+
+@pagination-hover-color:               #fff;
+@pagination-hover-bg:                  @brand-primary;
+@pagination-hover-border:              @brand-primary;
+
+@pagination-active-color:              #fff;
+@pagination-active-bg:                 @brand-primary;
+@pagination-active-border:             @brand-primary;
+
+@pagination-disabled-color:            @gray-light;
+@pagination-disabled-bg:               #fff;
+@pagination-disabled-border:           #ddd;
+
+
+//== Pager
+//
+//##
+
+@pager-bg:                             @pagination-bg;
+@pager-border:                         @pagination-border;
+@pager-border-radius:                  15px;
+
+@pager-hover-bg:                       @pagination-hover-bg;
+
+@pager-active-bg:                      @pagination-active-bg;
+@pager-active-color:                   @pagination-active-color;
+
+@pager-disabled-color:                 @gray-light;
+
+
+//== Jumbotron
+//
+//##
+
+@jumbotron-padding:              30px;
+@jumbotron-color:                inherit;
+@jumbotron-bg:                   darken(@body-bg, 3%);
+@jumbotron-heading-color:        inherit;
+@jumbotron-font-size:            ceil((@font-size-base * 1.5));
+
+
+//== Form states and alerts
+//
+//## Define colors for form feedback states and, by default, alerts.
+
+@state-success-text:             @brand-success;
+@state-success-bg:               #dff0d8;
+@state-success-border:           @brand-success;
+
+@state-info-text:                @brand-info;
+@state-info-bg:                  #d9edf7;
+@state-info-border:              @brand-info;
+
+@state-warning-text:             @brand-warning;
+@state-warning-bg:               #fcf8e3;
+@state-warning-border:           @brand-warning;
+
+@state-danger-text:              @brand-danger;
+@state-danger-bg:                #f2dede;
+@state-danger-border:            @brand-danger;
+
+
+//== Tooltips
+//
+//##
+
+//** Tooltip max width
+@tooltip-max-width:           200px;
+//** Tooltip text color
+@tooltip-color:               #fff;
+//** Tooltip background color
+@tooltip-bg:                  rgba(0,0,0,.9);
+@tooltip-opacity:             .9;
+
+//** Tooltip arrow width
+@tooltip-arrow-width:         5px;
+//** Tooltip arrow color
+@tooltip-arrow-color:         @tooltip-bg;
+
+
+//== Popovers
+//
+//##
+
+//** Popover body background color
+@popover-bg:                          #fff;
+//** Popover maximum width
+@popover-max-width:                   276px;
+//** Popover border color
+@popover-border-color:                rgba(0,0,0,.2);
+//** Popover fallback border color
+@popover-fallback-border-color:       #ccc;
+
+//** Popover title background color
+@popover-title-bg:                    darken(@popover-bg, 3%);
+
+//** Popover arrow width
+@popover-arrow-width:                 10px;
+//** Popover arrow color
+@popover-arrow-color:                 @popover-bg;
+
+//** Popover outer arrow width
+@popover-arrow-outer-width:           (@popover-arrow-width + 1);
+//** Popover outer arrow color
+@popover-arrow-outer-color:           fadein(@popover-border-color, 5%);
+//** Popover outer arrow fallback color
+@popover-arrow-outer-fallback-color:  darken(@popover-fallback-border-color, 20%);
+
+
+//== Labels
+//
+//##
+
+//** Default label background color
+@label-default-bg:            @btn-default-bg;
+//** Primary label background color
+@label-primary-bg:            @brand-primary;
+//** Success label background color
+@label-success-bg:            @brand-success;
+//** Info label background color
+@label-info-bg:               @brand-info;
+//** Warning label background color
+@label-warning-bg:            @brand-warning;
+//** Danger label background color
+@label-danger-bg:             @brand-danger;
+
+//** Default label text color
+@label-color:                 #fff;
+//** Default text color of a linked label
+@label-link-hover-color:      #fff;
+
+
+//== Modals
+//
+//##
+
+//** Padding applied to the modal body
+@modal-inner-padding:         20px;
+
+//** Padding applied to the modal title
+@modal-title-padding:         15px;
+//** Modal title line-height
+@modal-title-line-height:     @line-height-base;
+
+//** Background color of modal content area
+@modal-content-bg:                             #fff;
+//** Modal content border color
+@modal-content-border-color:                   rgba(0,0,0,.2);
+//** Modal content border color **for IE8**
+@modal-content-fallback-border-color:          #999;
+
+//** Modal backdrop background color
+@modal-backdrop-bg:           #000;
+//** Modal backdrop opacity
+@modal-backdrop-opacity:      .5;
+//** Modal header border color
+@modal-header-border-color:   #e5e5e5;
+//** Modal footer border color
+@modal-footer-border-color:   @modal-header-border-color;
+
+@modal-lg:                    900px;
+@modal-md:                    600px;
+@modal-sm:                    300px;
+
+
+//== Alerts
+//
+//## Define alert colors, border radius, and padding.
+
+@alert-padding:               15px;
+@alert-border-radius:         @border-radius-base;
+@alert-link-font-weight:      bold;
+
+@alert-success-bg:            @state-success-border;
+@alert-success-text:          #fff;
+@alert-success-border:        @state-success-border;
+
+@alert-info-bg:               @state-info-border;
+@alert-info-text:             #fff;
+@alert-info-border:           @state-info-border;
+
+@alert-warning-bg:            @state-warning-border;
+@alert-warning-text:          #fff;
+@alert-warning-border:        @state-warning-border;
+
+@alert-danger-bg:             @state-danger-border;
+@alert-danger-text:           #fff;
+@alert-danger-border:         @state-danger-border;
+
+
+//== Progress bars
+//
+//##
+
+//** Background color of the whole progress component
+@progress-bg:                 #f5f5f5;
+//** Progress bar text color
+@progress-bar-color:          #fff;
+//** Variable for setting rounded corners on progress bar.
+@progress-border-radius:      @border-radius-base;
+
+//** Default progress bar color
+@progress-bar-bg:             @brand-primary;
+//** Success progress bar color
+@progress-bar-success-bg:     @brand-success;
+//** Warning progress bar color
+@progress-bar-warning-bg:     @brand-warning;
+//** Danger progress bar color
+@progress-bar-danger-bg:      @brand-danger;
+//** Info progress bar color
+@progress-bar-info-bg:        @brand-info;
+
+
+//== List group
+//
+//##
+
+//** Background color on `.list-group-item`
+@list-group-bg:                 #fff;
+//** `.list-group-item` border color
+@list-group-border:             #ddd;
+//** List group border radius
+@list-group-border-radius:      @border-radius-base;
+
+//** Background color of single list items on hover
+@list-group-hover-bg:           #f5f5f5;
+//** Text color of active list items
+@list-group-active-color:       @component-active-color;
+//** Background color of active list items
+@list-group-active-bg:          @component-active-bg;
+//** Border color of active list elements
+@list-group-active-border:      @list-group-active-bg;
+//** Text color for content within active list items
+@list-group-active-text-color:  lighten(@list-group-active-bg, 40%);
+
+//** Text color of disabled list items
+@list-group-disabled-color:      @gray-light;
+//** Background color of disabled list items
+@list-group-disabled-bg:         @gray-lighter;
+//** Text color for content within disabled list items
+@list-group-disabled-text-color: @list-group-disabled-color;
+
+@list-group-link-color:         #555;
+@list-group-link-hover-color:   @list-group-link-color;
+@list-group-link-heading-color: #333;
+
+
+//== Panels
+//
+//##
+
+@panel-bg:                    #fff;
+@panel-body-padding:          15px;
+@panel-heading-padding:       10px 15px;
+@panel-footer-padding:        @panel-heading-padding;
+@panel-border-radius:         @border-radius-base;
+
+//** Border color for elements within panels
+@panel-inner-border:          #ddd;
+@panel-footer-bg:             #fff;
+
+@panel-default-text:          @gray-dark;
+@panel-default-border:        #ddd;
+@panel-default-heading-bg:    #f5f5f5;
+
+@panel-primary-text:          #fff;
+@panel-primary-border:        transparent;
+@panel-primary-heading-bg:    @brand-primary;
+
+@panel-success-text:          @state-success-text;
+@panel-success-border:        transparent;
+@panel-success-heading-bg:    @state-success-border;
+
+@panel-info-text:             @state-info-text;
+@panel-info-border:           transparent;
+@panel-info-heading-bg:       @state-info-border;
+
+@panel-warning-text:          @state-warning-text;
+@panel-warning-border:        transparent;
+@panel-warning-heading-bg:    @state-warning-border;
+
+@panel-danger-text:           @state-danger-text;
+@panel-danger-border:         transparent;
+@panel-danger-heading-bg:     @state-danger-border;
+
+
+//== Thumbnails
+//
+//##
+
+//** Padding around the thumbnail image
+@thumbnail-padding:           4px;
+//** Thumbnail background color
+@thumbnail-bg:                @body-bg;
+//** Thumbnail border color
+@thumbnail-border:            #ddd;
+//** Thumbnail border radius
+@thumbnail-border-radius:     @border-radius-base;
+
+//** Custom text color for thumbnail captions
+@thumbnail-caption-color:     @text-color;
+//** Padding around the thumbnail caption
+@thumbnail-caption-padding:   9px;
+
+
+//== Wells
+//
+//##
+
+@well-bg:                     darken(@body-bg, 3%);
+@well-border:                 darken(@well-bg, 7%);
+
+
+//== Badges
+//
+//##
+
+@badge-color:                 #fff;
+//** Linked badge text color on hover
+@badge-link-hover-color:      #fff;
+@badge-bg:                    @brand-primary;
+
+//** Badge text color in active nav link
+@badge-active-color:          @link-color;
+//** Badge background color in active nav link
+@badge-active-bg:             #fff;
+
+@badge-font-weight:           bold;
+@badge-line-height:           1;
+@badge-border-radius:         10px;
+
+
+//== Breadcrumbs
+//
+//##
+
+@breadcrumb-padding-vertical:   8px;
+@breadcrumb-padding-horizontal: 15px;
+//** Breadcrumb background color
+@breadcrumb-bg:                 #f5f5f5;
+//** Breadcrumb text color
+@breadcrumb-color:              #ccc;
+//** Text color of current page in the breadcrumb
+@breadcrumb-active-color:       @gray-light;
+//** Textual separator for between breadcrumb elements
+@breadcrumb-separator:          "/";
+
+
+//== Carousel
+//
+//##
+
+@carousel-text-shadow:                        0 1px 2px rgba(0,0,0,.6);
+
+@carousel-control-color:                      #fff;
+@carousel-control-width:                      15%;
+@carousel-control-opacity:                    .5;
+@carousel-control-font-size:                  20px;
+
+@carousel-indicator-active-bg:                #fff;
+@carousel-indicator-border-color:             #fff;
+
+@carousel-caption-color:                      #fff;
+
+
+//== Close
+//
+//##
+
+@close-font-weight:           bold;
+@close-color:                 #fff;
+@close-text-shadow:           0 1px 0 #fff;
+
+
+//== Code
+//
+//##
+
+@code-color:                  #c7254e;
+@code-bg:                     #f9f2f4;
+
+@kbd-color:                   #fff;
+@kbd-bg:                      #333;
+
+@pre-bg:                      #f5f5f5;
+@pre-color:                   @gray-dark;
+@pre-border-color:            #ccc;
+@pre-scrollable-max-height:   340px;
+
+
+//== Type
+//
+//##
+
+//** Horizontal offset for forms and lists.
+@component-offset-horizontal: 180px;
+//** Text muted color
+@text-muted:                  @gray-light;
+//** Abbreviations and acronyms border color
+@abbr-border-color:           @gray-light;
+//** Headings small color
+@headings-small-color:        @gray-light;
+//** Blockquote small color
+@blockquote-small-color:      @text-color;
+//** Blockquote font size
+@blockquote-font-size:        (@font-size-base * 1.25);
+//** Blockquote border color
+@blockquote-border-color:     @brand-primary;
+//** Page header border color
+@page-header-border-color:    #ddd;
+//** Width of horizontal description list titles
+@dl-horizontal-offset:        @component-offset-horizontal;
+//** Horizontal line color.
+@hr-border:                   @gray-lighter;
diff --git a/searx/static/less/bootstrap/theme_simplex/bootswatch.less b/searx/static/less/bootstrap/theme_simplex/bootswatch.less
new file mode 100644
index 000000000..b0e4323d4
--- /dev/null
+++ b/searx/static/less/bootstrap/theme_simplex/bootswatch.less
@@ -0,0 +1,142 @@
+// Simplex 3.3.1
+// Bootswatch
+// -----------------------------------------------------
+
+@import url("//fonts.googleapis.com/css?family=Open+Sans:400,700");
+
+.btn-shadow(@color) {
+  #gradient > .vertical-three-colors(lighten(@color, 3%), @color, 6%, darken(@color, 3%));
+  filter: none;
+  border: 1px solid darken(@color, 10%);
+}
+
+// Navbar =====================================================================
+
+.navbar {
+
+  &-inverse {
+
+    .badge {
+      background-color: #fff;
+      color: @brand-primary;
+    }
+  }
+}
+
+// Buttons ====================================================================
+
+.btn {
+  font-family: @headings-font-family;
+}
+
+.btn-default,
+.btn-default:hover {
+  .btn-shadow(@btn-default-bg);
+}
+
+.btn-primary,
+.btn-primary:hover {
+  .btn-shadow(@btn-primary-bg);
+}
+
+.btn-success,
+.btn-success:hover {
+  .btn-shadow(@btn-success-bg);
+}
+
+.btn-info,
+.btn-info:hover {
+  .btn-shadow(@btn-info-bg);
+}
+
+.btn-warning,
+.btn-warning:hover {
+  .btn-shadow(@btn-warning-bg);
+}
+
+.btn-danger,
+.btn-danger:hover {
+  .btn-shadow(@btn-danger-bg);
+}
+
+// Typography =================================================================
+
+body {
+  font-weight: 200;
+}
+
+// Tables =====================================================================
+
+th {
+  color: @headings-color;
+}
+
+// Forms ======================================================================
+
+legend {
+  color: @headings-color;
+}
+
+label {
+  font-weight: normal;
+}
+
+.has-warning {
+  .help-block,
+  .control-label {
+    color: @brand-danger;
+  }
+
+  .form-control,
+  .form-control:focus {
+    border-color: @brand-danger;
+  }
+}
+
+.has-error {
+  .help-block,
+  .control-label {
+    color: @brand-primary;
+  }
+
+  .form-control,
+  .form-control:focus {
+    border-color: @brand-primary;
+  }
+}
+
+.has-success {
+  .help-block,
+  .control-label {
+    color: @brand-success;
+  }
+
+  .form-control,
+  .form-control:focus {
+    border-color: @brand-success;
+  }
+}
+
+// Navs =======================================================================
+
+.pager {
+  a {
+    color: @headings-color;
+  }
+
+  a:hover,
+  .active > a, {
+    border-color: @brand-primary;
+    color: #fff;
+  }
+
+  .disabled > a {
+    border-color: @pager-border;
+  }
+}
+
+// Indicators =================================================================
+
+// Progress bars ==============================================================
+
+// Containers =================================================================
\ No newline at end of file
diff --git a/searx/static/less/bootstrap/theme_simplex/variables.less b/searx/static/less/bootstrap/theme_simplex/variables.less
new file mode 100644
index 000000000..d3477b349
--- /dev/null
+++ b/searx/static/less/bootstrap/theme_simplex/variables.less
@@ -0,0 +1,856 @@
+// Simplex 3.3.1
+// Variables
+// --------------------------------------------------
+
+
+//== Colors
+//
+//## Gray and brand colors for use across Bootstrap.
+
+@gray-base:              #000;
+@gray-darker:            lighten(@gray-base, 13.5%); // #222
+@gray-dark:              #444;
+@gray:                   #777;
+@gray-light:             #808080;
+@gray-lighter:           #ddd;
+
+@brand-primary:         #D9230F;
+@brand-success:         #469408;
+@brand-info:            #029ACF;
+@brand-warning:         #9B479F;
+@brand-danger:          #D9831F;
+
+
+//== Scaffolding
+//
+//## Settings for some of the most global styles.
+
+//** Background color for `<body>`.
+@body-bg:               #FCFCFC;
+//** Global text color on `<body>`.
+@text-color:            @gray;
+
+//** Global textual link color.
+@link-color:            @brand-primary;
+//** Link hover color set via `darken()` function.
+@link-hover-color:      darken(@link-color, 15%);
+//** Link hover decoration.
+@link-hover-decoration: underline;
+
+
+//== Typography
+//
+//## Font, line-height, and color for body text, headings, and more.
+
+@font-family-sans-serif:  "Open Sans", "Helvetica Neue", Helvetica, Arial, sans-serif;
+@font-family-serif:       Georgia, "Times New Roman", Times, serif;
+//** Default monospace fonts for `<code>`, `<kbd>`, and `<pre>`.
+@font-family-monospace:   Menlo, Monaco, Consolas, "Courier New", monospace;
+@font-family-base:        @font-family-sans-serif;
+
+@font-size-base:          13px;
+@font-size-large:         ceil((@font-size-base * 1.25)); // ~18px
+@font-size-small:         ceil((@font-size-base * 0.85)); // ~12px
+
+@font-size-h1:            floor((@font-size-base * 2.6)); // ~36px
+@font-size-h2:            floor((@font-size-base * 2.15)); // ~30px
+@font-size-h3:            ceil((@font-size-base * 1.7)); // ~24px
+@font-size-h4:            ceil((@font-size-base * 1.25)); // ~18px
+@font-size-h5:            @font-size-base;
+@font-size-h6:            ceil((@font-size-base * 0.85)); // ~12px
+
+//** Unit-less `line-height` for use in components like buttons.
+@line-height-base:        1.428571429; // 20/14
+//** Computed "line-height" (`font-size` * `line-height`) for use with `margin`, `padding`, etc.
+@line-height-computed:    floor((@font-size-base * @line-height-base)); // ~20px
+
+//** By default, this inherits from the `<body>`.
+@headings-font-family:    @font-family-sans-serif;
+@headings-font-weight:    300;
+@headings-line-height:    1.1;
+@headings-color:          @gray-dark;
+
+
+//== Iconography
+//
+//## Specify custom location and filename of the included Glyphicons icon font. Useful for those including Bootstrap via Bower.
+
+//** Load fonts from this directory.
+@icon-font-path:          "../fonts/";
+//** File name for all font files.
+@icon-font-name:          "glyphicons-halflings-regular";
+//** Element ID within SVG icon file.
+@icon-font-svg-id:        "glyphicons_halflingsregular";
+
+
+//== Components
+//
+//## Define common padding and border radius sizes and more. Values based on 14px text and 1.428 line-height (~20px to start).
+
+@padding-base-vertical:     8px;
+@padding-base-horizontal:   12px;
+
+@padding-large-vertical:    14px;
+@padding-large-horizontal:  16px;
+
+@padding-small-vertical:    5px;
+@padding-small-horizontal:  10px;
+
+@padding-xs-vertical:       1px;
+@padding-xs-horizontal:     5px;
+
+@line-height-large:         1.33;
+@line-height-small:         1.5;
+
+@border-radius-base:        4px;
+@border-radius-large:       6px;
+@border-radius-small:       3px;
+
+//** Global color for active items (e.g., navs or dropdowns).
+@component-active-color:    #fff;
+//** Global background color for active items (e.g., navs or dropdowns).
+@component-active-bg:       @brand-primary;
+
+//** Width of the `border` for generating carets that indicator dropdowns.
+@caret-width-base:          4px;
+//** Carets increase slightly in size for larger components.
+@caret-width-large:         5px;
+
+
+//== Tables
+//
+//## Customizes the `.table` component with basic values, each used across all table variations.
+
+//** Padding for `<th>`s and `<td>`s.
+@table-cell-padding:            8px;
+//** Padding for cells in `.table-condensed`.
+@table-condensed-cell-padding:  5px;
+
+//** Default background color used for all tables.
+@table-bg:                      transparent;
+//** Background color used for `.table-striped`.
+@table-bg-accent:               #f9f9f9;
+//** Background color used for `.table-hover`.
+@table-bg-hover:                #f5f5f5;
+@table-bg-active:               @table-bg-hover;
+
+//** Border color for table and cell borders.
+@table-border-color:            #ddd;
+
+
+//== Buttons
+//
+//## For each of Bootstrap's buttons, define text, background and border color.
+
+@btn-font-weight:                normal;
+
+@btn-default-color:              #fff;
+@btn-default-bg:                 #474949;
+@btn-default-border:             @btn-default-bg;
+
+@btn-primary-color:              @btn-default-color;
+@btn-primary-bg:                 @brand-primary;
+@btn-primary-border:             @btn-primary-bg;
+
+@btn-success-color:              @btn-default-color;
+@btn-success-bg:                 @brand-success;
+@btn-success-border:             @btn-success-bg;
+
+@btn-info-color:                 @btn-default-color;
+@btn-info-bg:                    @brand-info;
+@btn-info-border:                @btn-info-bg;
+
+@btn-warning-color:              @btn-default-color;
+@btn-warning-bg:                 @brand-warning;
+@btn-warning-border:             @btn-warning-bg;
+
+@btn-danger-color:               @btn-default-color;
+@btn-danger-bg:                  @brand-danger;
+@btn-danger-border:              @btn-danger-bg;
+
+@btn-link-disabled-color:        @gray-light;
+
+
+//== Forms
+//
+//##
+
+//** `<input>` background color
+@input-bg:                       #fff;
+//** `<input disabled>` background color
+@input-bg-disabled:              @gray-lighter;
+
+//** Text color for `<input>`s
+@input-color:                    @text-color;
+//** `<input>` border color
+@input-border:                   #ddd;
+
+// TODO: Rename `@input-border-radius` to `@input-border-radius-base` in v4
+//** Default `.form-control` border radius
+@input-border-radius:            @border-radius-base;
+//** Large `.form-control` border radius
+@input-border-radius-large:      @border-radius-large;
+//** Small `.form-control` border radius
+@input-border-radius-small:      @border-radius-small;
+
+//** Border color for inputs on focus
+@input-border-focus:             #66afe9;
+
+//** Placeholder text color
+@input-color-placeholder:        @gray-lighter;
+
+//** Default `.form-control` height
+@input-height-base:              (@line-height-computed + (@padding-base-vertical * 2) + 2);
+//** Large `.form-control` height
+@input-height-large:             (ceil(@font-size-large * @line-height-large) + (@padding-large-vertical * 2) + 2);
+//** Small `.form-control` height
+@input-height-small:             (floor(@font-size-small * @line-height-small) + (@padding-small-vertical * 2) + 2);
+
+@legend-color:                   @text-color;
+@legend-border-color:            #e5e5e5;
+
+//** Background color for textual input addons
+@input-group-addon-bg:           @gray-lighter;
+//** Border color for textual input addons
+@input-group-addon-border-color: @input-border;
+
+//** Disabled cursor for form controls and buttons.
+@cursor-disabled:                not-allowed;
+
+
+//== Dropdowns
+//
+//## Dropdown menu container and contents.
+
+//** Background for the dropdown menu.
+@dropdown-bg:                    #fff;
+//** Dropdown menu `border-color`.
+@dropdown-border:                rgba(0,0,0,.15);
+//** Dropdown menu `border-color` **for IE8**.
+@dropdown-fallback-border:       #ccc;
+//** Divider color for between dropdown items.
+@dropdown-divider-bg:            #e5e5e5;
+
+//** Dropdown link text color.
+@dropdown-link-color:            @gray-dark;
+//** Hover color for dropdown links.
+@dropdown-link-hover-color:      #fff;
+//** Hover background for dropdown links.
+@dropdown-link-hover-bg:         @component-active-bg;
+
+//** Active dropdown menu item text color.
+@dropdown-link-active-color:     #fff;
+//** Active dropdown menu item background color.
+@dropdown-link-active-bg:        @component-active-bg;
+
+//** Disabled dropdown menu item background color.
+@dropdown-link-disabled-color:   @gray-light;
+
+//** Text color for headers within dropdown menus.
+@dropdown-header-color:          @gray-light;
+
+//** Deprecated `@dropdown-caret-color` as of v3.1.0
+@dropdown-caret-color:           #000;
+
+
+//-- Z-index master list
+//
+// Warning: Avoid customizing these values. They're used for a bird's eye view
+// of components dependent on the z-axis and are designed to all work together.
+//
+// Note: These variables are not generated into the Customizer.
+
+@zindex-navbar:            1000;
+@zindex-dropdown:          1000;
+@zindex-popover:           1060;
+@zindex-tooltip:           1070;
+@zindex-navbar-fixed:      1030;
+@zindex-modal:             1040;
+
+
+//== Media queries breakpoints
+//
+//## Define the breakpoints at which your layout will change, adapting to different screen sizes.
+
+// Extra small screen / phone
+//** Deprecated `@screen-xs` as of v3.0.1
+@screen-xs:                  480px;
+//** Deprecated `@screen-xs-min` as of v3.2.0
+@screen-xs-min:              @screen-xs;
+//** Deprecated `@screen-phone` as of v3.0.1
+@screen-phone:               @screen-xs-min;
+
+// Small screen / tablet
+//** Deprecated `@screen-sm` as of v3.0.1
+@screen-sm:                  768px;
+@screen-sm-min:              @screen-sm;
+//** Deprecated `@screen-tablet` as of v3.0.1
+@screen-tablet:              @screen-sm-min;
+
+// Medium screen / desktop
+//** Deprecated `@screen-md` as of v3.0.1
+@screen-md:                  992px;
+@screen-md-min:              @screen-md;
+//** Deprecated `@screen-desktop` as of v3.0.1
+@screen-desktop:             @screen-md-min;
+
+// Large screen / wide desktop
+//** Deprecated `@screen-lg` as of v3.0.1
+@screen-lg:                  1200px;
+@screen-lg-min:              @screen-lg;
+//** Deprecated `@screen-lg-desktop` as of v3.0.1
+@screen-lg-desktop:          @screen-lg-min;
+
+// So media queries don't overlap when required, provide a maximum
+@screen-xs-max:              (@screen-sm-min - 1);
+@screen-sm-max:              (@screen-md-min - 1);
+@screen-md-max:              (@screen-lg-min - 1);
+
+
+//== Grid system
+//
+//## Define your custom responsive grid.
+
+//** Number of columns in the grid.
+@grid-columns:              12;
+//** Padding between columns. Gets divided in half for the left and right.
+@grid-gutter-width:         30px;
+// Navbar collapse
+//** Point at which the navbar becomes uncollapsed.
+@grid-float-breakpoint:     @screen-sm-min;
+//** Point at which the navbar begins collapsing.
+@grid-float-breakpoint-max: (@grid-float-breakpoint - 1);
+
+
+//== Container sizes
+//
+//## Define the maximum width of `.container` for different screen sizes.
+
+// Small screen / tablet
+@container-tablet:             (720px + @grid-gutter-width);
+//** For `@screen-sm-min` and up.
+@container-sm:                 @container-tablet;
+
+// Medium screen / desktop
+@container-desktop:            (940px + @grid-gutter-width);
+//** For `@screen-md-min` and up.
+@container-md:                 @container-desktop;
+
+// Large screen / wide desktop
+@container-large-desktop:      (1140px + @grid-gutter-width);
+//** For `@screen-lg-min` and up.
+@container-lg:                 @container-large-desktop;
+
+
+//== Navbar
+//
+//##
+
+// Basics of a navbar
+@navbar-height:                    40px;
+@navbar-margin-bottom:             @line-height-computed;
+@navbar-border-radius:             @border-radius-base;
+@navbar-padding-horizontal:        floor((@grid-gutter-width / 2));
+@navbar-padding-vertical:          ((@navbar-height - @line-height-computed) / 2);
+@navbar-collapse-max-height:       340px;
+
+@navbar-default-color:             @gray;
+@navbar-default-bg:                #fff;
+@navbar-default-border:            darken(@navbar-default-bg, 6.5%);
+
+// Navbar links
+@navbar-default-link-color:                @gray;
+@navbar-default-link-hover-color:          @brand-primary;
+@navbar-default-link-hover-bg:             transparent;
+@navbar-default-link-active-color:         @navbar-default-link-hover-color;
+@navbar-default-link-active-bg:            transparent;
+@navbar-default-link-disabled-color:       #444;
+@navbar-default-link-disabled-bg:          transparent;
+
+// Navbar brand label
+@navbar-default-brand-color:               @navbar-default-link-color;
+@navbar-default-brand-hover-color:         @navbar-default-link-hover-color;
+@navbar-default-brand-hover-bg:            transparent;
+
+// Navbar toggle
+@navbar-default-toggle-hover-bg:           #ddd;
+@navbar-default-toggle-icon-bar-bg:        #ccc;
+@navbar-default-toggle-border-color:       #ddd;
+
+
+// Inverted navbar
+// Reset inverted navbar basics
+@navbar-inverse-color:                      lighten(@brand-primary, 40%);
+@navbar-inverse-bg:                         @brand-primary;
+@navbar-inverse-border:                     darken(@navbar-inverse-bg, 10%);
+
+// Inverted navbar links
+@navbar-inverse-link-color:                 lighten(@brand-primary, 40%);
+@navbar-inverse-link-hover-color:           #fff;
+@navbar-inverse-link-hover-bg:              transparent;
+@navbar-inverse-link-active-color:          @navbar-inverse-link-hover-color;
+@navbar-inverse-link-active-bg:             transparent;
+@navbar-inverse-link-disabled-color:        #ccc;
+@navbar-inverse-link-disabled-bg:           transparent;
+
+// Inverted navbar brand label
+@navbar-inverse-brand-color:                @navbar-inverse-link-color;
+@navbar-inverse-brand-hover-color:          #fff;
+@navbar-inverse-brand-hover-bg:             transparent;
+
+// Inverted navbar toggle
+@navbar-inverse-toggle-hover-bg:            darken(@navbar-inverse-bg, 10%);
+@navbar-inverse-toggle-icon-bar-bg:         #fff;
+@navbar-inverse-toggle-border-color:        darken(@navbar-inverse-bg, 10%);
+
+
+//== Navs
+//
+//##
+
+//=== Shared nav styles
+@nav-link-padding:                          10px 15px;
+@nav-link-hover-bg:                         @gray-lighter;
+
+@nav-disabled-link-color:                   @gray-light;
+@nav-disabled-link-hover-color:             @gray-light;
+
+//== Tabs
+@nav-tabs-border-color:                     #ddd;
+
+@nav-tabs-link-hover-border-color:          @gray-lighter;
+
+@nav-tabs-active-link-hover-bg:             @body-bg;
+@nav-tabs-active-link-hover-color:          @gray;
+@nav-tabs-active-link-hover-border-color:   #ddd;
+
+@nav-tabs-justified-link-border-color:            #ddd;
+@nav-tabs-justified-active-link-border-color:     @body-bg;
+
+//== Pills
+@nav-pills-border-radius:                   @border-radius-base;
+@nav-pills-active-link-hover-bg:            @component-active-bg;
+@nav-pills-active-link-hover-color:         @component-active-color;
+
+
+//== Pagination
+//
+//##
+
+@pagination-color:                     @headings-color;
+@pagination-bg:                        #fff;
+@pagination-border:                    #ddd;
+
+@pagination-hover-color:               #fff;
+@pagination-hover-bg:                  @brand-primary;
+@pagination-hover-border:              @brand-primary;
+
+@pagination-active-color:              #fff;
+@pagination-active-bg:                 @brand-primary;
+@pagination-active-border:             @brand-primary;
+
+@pagination-disabled-color:            @gray-lighter;
+@pagination-disabled-bg:               #fff;
+@pagination-disabled-border:           #ddd;
+
+
+//== Pager
+//
+//##
+
+@pager-bg:                             @pagination-bg;
+@pager-border:                         @pagination-border;
+@pager-border-radius:                  15px;
+
+@pager-hover-bg:                       @brand-primary;
+
+@pager-active-bg:                      @brand-primary;
+@pager-active-color:                   #fff;
+
+@pager-disabled-color:                 @gray-lighter;
+
+
+//== Jumbotron
+//
+//##
+
+@jumbotron-padding:              30px;
+@jumbotron-color:                inherit;
+@jumbotron-bg:                   darken(@body-bg, 3%);
+@jumbotron-heading-color:        inherit;
+@jumbotron-font-size:            ceil((@font-size-base * 1.5));
+
+
+//== Form states and alerts
+//
+//## Define colors for form feedback states and, by default, alerts.
+
+@state-success-text:             #468847;
+@state-success-bg:               #dff0d8;
+@state-success-border:           darken(spin(@state-success-bg, -10), 5%);
+
+@state-info-text:                #3a87ad;
+@state-info-bg:                  #d9edf7;
+@state-info-border:              darken(spin(@state-info-bg, -10), 7%);
+
+@state-warning-text:             #c09853;
+@state-warning-bg:               #fcf8e3;
+@state-warning-border:           darken(spin(@state-warning-bg, -10), 3%);
+
+@state-danger-text:              #b94a48;
+@state-danger-bg:                #f2dede;
+@state-danger-border:            darken(spin(@state-danger-bg, -10), 3%);
+
+
+//== Tooltips
+//
+//##
+
+//** Tooltip max width
+@tooltip-max-width:           200px;
+//** Tooltip text color
+@tooltip-color:               #fff;
+//** Tooltip background color
+@tooltip-bg:                  rgba(0,0,0,.9);
+@tooltip-opacity:             .9;
+
+//** Tooltip arrow width
+@tooltip-arrow-width:         5px;
+//** Tooltip arrow color
+@tooltip-arrow-color:         @tooltip-bg;
+
+
+//== Popovers
+//
+//##
+
+//** Popover body background color
+@popover-bg:                          #fff;
+//** Popover maximum width
+@popover-max-width:                   276px;
+//** Popover border color
+@popover-border-color:                rgba(0,0,0,.2);
+//** Popover fallback border color
+@popover-fallback-border-color:       #ccc;
+
+//** Popover title background color
+@popover-title-bg:                    darken(@popover-bg, 3%);
+
+//** Popover arrow width
+@popover-arrow-width:                 10px;
+//** Popover arrow color
+@popover-arrow-color:                 @popover-bg;
+
+//** Popover outer arrow width
+@popover-arrow-outer-width:           (@popover-arrow-width + 1);
+//** Popover outer arrow color
+@popover-arrow-outer-color:           fadein(@popover-border-color, 5%);
+//** Popover outer arrow fallback color
+@popover-arrow-outer-fallback-color:  darken(@popover-fallback-border-color, 20%);
+
+
+//== Labels
+//
+//##
+
+//** Default label background color
+@label-default-bg:            @btn-default-bg;
+//** Primary label background color
+@label-primary-bg:            @brand-primary;
+//** Success label background color
+@label-success-bg:            @brand-success;
+//** Info label background color
+@label-info-bg:               @brand-info;
+//** Warning label background color
+@label-warning-bg:            @brand-warning;
+//** Danger label background color
+@label-danger-bg:             @brand-danger;
+
+//** Default label text color
+@label-color:                 #fff;
+//** Default text color of a linked label
+@label-link-hover-color:      #fff;
+
+
+//== Modals
+//
+//##
+
+//** Padding applied to the modal body
+@modal-inner-padding:         20px;
+
+//** Padding applied to the modal title
+@modal-title-padding:         15px;
+//** Modal title line-height
+@modal-title-line-height:     @line-height-base;
+
+//** Background color of modal content area
+@modal-content-bg:                             #fff;
+//** Modal content border color
+@modal-content-border-color:                   rgba(0,0,0,.2);
+//** Modal content border color **for IE8**
+@modal-content-fallback-border-color:          #999;
+
+//** Modal backdrop background color
+@modal-backdrop-bg:           #000;
+//** Modal backdrop opacity
+@modal-backdrop-opacity:      .5;
+//** Modal header border color
+@modal-header-border-color:   #e5e5e5;
+//** Modal footer border color
+@modal-footer-border-color:   @modal-header-border-color;
+
+@modal-lg:                    900px;
+@modal-md:                    600px;
+@modal-sm:                    300px;
+
+
+//== Alerts
+//
+//## Define alert colors, border radius, and padding.
+
+@alert-padding:               15px;
+@alert-border-radius:         @border-radius-base;
+@alert-link-font-weight:      bold;
+
+@alert-success-bg:            @state-success-bg;
+@alert-success-text:          @state-success-text;
+@alert-success-border:        @state-success-border;
+
+@alert-info-bg:               @state-info-bg;
+@alert-info-text:             @state-info-text;
+@alert-info-border:           @state-info-border;
+
+@alert-warning-bg:            @state-warning-bg;
+@alert-warning-text:          @state-warning-text;
+@alert-warning-border:        @state-warning-border;
+
+@alert-danger-bg:             @state-danger-bg;
+@alert-danger-text:           @state-danger-text;
+@alert-danger-border:         @state-danger-border;
+
+
+//== Progress bars
+//
+//##
+
+//** Background color of the whole progress component
+@progress-bg:                 #f5f5f5;
+//** Progress bar text color
+@progress-bar-color:          #fff;
+//** Variable for setting rounded corners on progress bar.
+@progress-border-radius:      @border-radius-base;
+
+//** Default progress bar color
+@progress-bar-bg:             @brand-primary;
+//** Success progress bar color
+@progress-bar-success-bg:     @brand-success;
+//** Warning progress bar color
+@progress-bar-warning-bg:     @brand-warning;
+//** Danger progress bar color
+@progress-bar-danger-bg:      @brand-danger;
+//** Info progress bar color
+@progress-bar-info-bg:        @brand-info;
+
+
+//== List group
+//
+//##
+
+//** Background color on `.list-group-item`
+@list-group-bg:                 #fff;
+//** `.list-group-item` border color
+@list-group-border:             #ddd;
+//** List group border radius
+@list-group-border-radius:      @border-radius-base;
+
+//** Background color of single list items on hover
+@list-group-hover-bg:           #f5f5f5;
+//** Text color of active list items
+@list-group-active-color:       @component-active-color;
+//** Background color of active list items
+@list-group-active-bg:          @component-active-bg;
+//** Border color of active list elements
+@list-group-active-border:      @list-group-active-bg;
+//** Text color for content within active list items
+@list-group-active-text-color:  lighten(@list-group-active-bg, 40%);
+
+//** Text color of disabled list items
+@list-group-disabled-color:      @gray-light;
+//** Background color of disabled list items
+@list-group-disabled-bg:         @gray-lighter;
+//** Text color for content within disabled list items
+@list-group-disabled-text-color: @list-group-disabled-color;
+
+@list-group-link-color:         #555;
+@list-group-link-hover-color:   @list-group-link-color;
+@list-group-link-heading-color: #333;
+
+
+//== Panels
+//
+//##
+
+@panel-bg:                    #fff;
+@panel-body-padding:          15px;
+@panel-heading-padding:       10px 15px;
+@panel-footer-padding:        @panel-heading-padding;
+@panel-border-radius:         @border-radius-base;
+
+//** Border color for elements within panels
+@panel-inner-border:          #ddd;
+@panel-footer-bg:             @body-bg;
+
+@panel-default-text:          @gray-dark;
+@panel-default-border:        #ddd;
+@panel-default-heading-bg:    @panel-footer-bg;
+
+@panel-primary-text:          #fff;
+@panel-primary-border:        @brand-primary;
+@panel-primary-heading-bg:    @brand-primary;
+
+@panel-success-text:          #fff;
+@panel-success-border:        @brand-success;
+@panel-success-heading-bg:    @brand-success;
+
+@panel-info-text:             #fff;
+@panel-info-border:           @brand-info;
+@panel-info-heading-bg:       @brand-info;
+
+@panel-warning-text:          #fff;
+@panel-warning-border:        @brand-warning;
+@panel-warning-heading-bg:    @brand-warning;
+
+@panel-danger-text:           #fff;
+@panel-danger-border:         @brand-danger;
+@panel-danger-heading-bg:     @brand-danger;
+
+
+//== Thumbnails
+//
+//##
+
+//** Padding around the thumbnail image
+@thumbnail-padding:           4px;
+//** Thumbnail background color
+@thumbnail-bg:                @body-bg;
+//** Thumbnail border color
+@thumbnail-border:            #ddd;
+//** Thumbnail border radius
+@thumbnail-border-radius:     @border-radius-base;
+
+//** Custom text color for thumbnail captions
+@thumbnail-caption-color:     @text-color;
+//** Padding around the thumbnail caption
+@thumbnail-caption-padding:   9px;
+
+
+//== Wells
+//
+//##
+
+@well-bg:                     darken(@body-bg, 3%);
+@well-border:                 darken(@well-bg, 7%);
+
+
+//== Badges
+//
+//##
+
+@badge-color:                 #fff;
+//** Linked badge text color on hover
+@badge-link-hover-color:      #fff;
+@badge-bg:                    @link-color;
+
+//** Badge text color in active nav link
+@badge-active-color:          @link-color;
+//** Badge background color in active nav link
+@badge-active-bg:             #fff;
+
+@badge-font-weight:           bold;
+@badge-line-height:           1;
+@badge-border-radius:         10px;
+
+
+//== Breadcrumbs
+//
+//##
+
+@breadcrumb-padding-vertical:   8px;
+@breadcrumb-padding-horizontal: 15px;
+//** Breadcrumb background color
+@breadcrumb-bg:                 transparent;
+//** Breadcrumb text color
+@breadcrumb-color:              #ccc;
+//** Text color of current page in the breadcrumb
+@breadcrumb-active-color:       @gray-light;
+//** Textual separator for between breadcrumb elements
+@breadcrumb-separator:          "/";
+
+
+//== Carousel
+//
+//##
+
+@carousel-text-shadow:                        0 1px 2px rgba(0,0,0,.6);
+
+@carousel-control-color:                      #fff;
+@carousel-control-width:                      15%;
+@carousel-control-opacity:                    .5;
+@carousel-control-font-size:                  20px;
+
+@carousel-indicator-active-bg:                #fff;
+@carousel-indicator-border-color:             #fff;
+
+@carousel-caption-color:                      #fff;
+
+
+//== Close
+//
+//##
+
+@close-font-weight:           bold;
+@close-color:                 #000;
+@close-text-shadow:           0 1px 0 #fff;
+
+
+//== Code
+//
+//##
+
+@code-color:                  #c7254e;
+@code-bg:                     #f9f2f4;
+
+@kbd-color:                   #fff;
+@kbd-bg:                      #333;
+
+@pre-bg:                      #f5f5f5;
+@pre-color:                   @gray-dark;
+@pre-border-color:            #ccc;
+@pre-scrollable-max-height:   340px;
+
+
+//== Type
+//
+//##
+
+//** Horizontal offset for forms and lists.
+@component-offset-horizontal: 180px;
+//** Text muted color
+@text-muted:                  @gray-light;
+//** Abbreviations and acronyms border color
+@abbr-border-color:           @gray-light;
+//** Headings small color
+@headings-small-color:        @gray-light;
+//** Blockquote small color
+@blockquote-small-color:      @gray-light;
+//** Blockquote font size
+@blockquote-font-size:        (@font-size-base * 1.25);
+//** Blockquote border color
+@blockquote-border-color:     @gray-lighter;
+//** Page header border color
+@page-header-border-color:    @gray-lighter;
+//** Width of horizontal description list titles
+@dl-horizontal-offset:        @component-offset-horizontal;
+//** Horizontal line color.
+@hr-border:                   @gray-lighter;
diff --git a/searx/static/less/bootstrap/theme_yeti/bootswatch.less b/searx/static/less/bootstrap/theme_yeti/bootswatch.less
new file mode 100644
index 000000000..44ab1c71a
--- /dev/null
+++ b/searx/static/less/bootstrap/theme_yeti/bootswatch.less
@@ -0,0 +1,437 @@
+// Yeti 3.3.1
+// Bootswatch
+// -----------------------------------------------------
+
+@import url("//fonts.googleapis.com/css?family=Open+Sans:300italic,400italic,700italic,400,300,700");
+
+// Navbar =====================================================================
+
+.navbar {
+  border: none;
+  font-size: 13px;
+  font-weight: 300;
+
+  .navbar-toggle:hover .icon-bar {
+    background-color: #b3b3b3;
+  }
+
+  &-collapse {
+    border-top-color: @dropdown-divider-bg;
+    .box-shadow(none);
+  }
+
+  .btn {
+    padding-top: 6px;
+    padding-bottom: 6px;
+  }
+
+  &-form {
+    margin-top: 7px;
+    margin-bottom: 5px;
+
+    .form-control {
+      height: auto;
+      padding: @padding-xs-vertical @padding-xs-horizontal;
+    }
+  }
+
+  .dropdown {
+
+    &-menu {
+      border: none;
+
+      > li > a,
+      > li > a:focus {
+        background-color: transparent;
+        font-size: 13px;
+        font-weight: 300;
+      }
+    }
+
+    &-header {
+      color: rgba(255, 255, 255, 0.5);
+    }
+
+  }
+
+  &-default {
+
+    .dropdown-menu {
+      background-color: @navbar-default-bg;
+
+      > li > a,
+      > li > a:focus {
+        color: @navbar-default-color;
+      }
+
+      > li > a:hover,
+      > .active > a,
+      > .active > a:hover {
+        background-color: @navbar-default-link-hover-bg;
+      }
+    }
+  }
+
+  &-inverse {
+
+    .dropdown-menu {
+      background-color: @navbar-inverse-bg;
+
+      > li > a,
+      > li > a:focus {
+        color: @navbar-inverse-color;
+      }
+
+      > li > a:hover,
+      > .active > a,
+      > .active > a:hover {
+        background-color: @navbar-inverse-link-hover-bg;
+      }
+    }
+  }
+}
+
+// Buttons ====================================================================
+
+.btn {
+  padding: @padding-base-vertical @padding-base-horizontal;
+
+  &-lg {
+    padding: @padding-large-vertical @padding-large-horizontal;
+  }
+
+  &-sm {
+    padding: @padding-small-vertical @padding-small-horizontal;
+  }
+
+  &-xs {
+    padding: @padding-xs-vertical @padding-xs-horizontal;
+  }
+}
+
+.btn-group {
+
+  .btn ~ .dropdown-toggle {
+    padding-left: 16px;
+    padding-right: 16px;
+  }
+
+  .dropdown-menu {
+    border-top-width: 0;
+  }
+
+  &.dropup .dropdown-menu {
+    border-top-width: 1px;
+    border-bottom-width: 0;
+    margin-bottom: 0;
+  }
+
+  .dropdown-toggle {
+
+    &.btn-default ~ .dropdown-menu {
+      background-color: @btn-default-bg;
+      border-color: @btn-default-border;
+
+      > li > a {
+        color: @btn-default-color;
+      }
+
+      > li > a:hover {
+        background-color: darken(@btn-default-bg, 8%);
+      }
+    }
+
+    &.btn-primary ~ .dropdown-menu {
+      background-color: @btn-primary-bg;
+      border-color: @btn-primary-border;
+
+      > li > a {
+        color: @btn-primary-color;
+      }
+
+      > li > a:hover {
+        background-color: darken(@btn-primary-bg, 8%);
+      }
+    }
+
+    &.btn-success ~ .dropdown-menu {
+      background-color: @btn-success-bg;
+      border-color: @btn-success-border;
+
+      > li > a {
+        color: @btn-success-color;
+      }
+
+      > li > a:hover {
+        background-color: darken(@btn-success-bg, 8%);
+      }
+    }
+
+    &.btn-info ~ .dropdown-menu {
+      background-color: @btn-info-bg;
+      border-color: @btn-info-border;
+
+      > li > a {
+        color: @btn-info-color;
+      }
+
+      > li > a:hover {
+        background-color: darken(@btn-info-bg, 8%);
+      }
+    }
+
+    &.btn-warning ~ .dropdown-menu {
+      background-color: @btn-warning-bg;
+      border-color: @btn-warning-border;
+
+      > li > a {
+        color: @btn-warning-color;
+      }
+
+      > li > a:hover {
+        background-color: darken(@btn-warning-bg, 8%);
+      }
+    }
+
+    &.btn-danger ~ .dropdown-menu {
+      background-color: @btn-danger-bg;
+      border-color: @btn-danger-border;
+
+      > li > a {
+        color: @btn-danger-color;
+      }
+
+      > li > a:hover {
+        background-color: darken(@btn-danger-bg, 8%);
+      }
+    }
+  }
+}
+
+// Typography =================================================================
+
+.lead {
+  color: @gray;
+}
+
+cite {
+  font-style: italic;
+}
+
+blockquote {
+  border-left-width: 1px;
+  color: @gray;
+
+  &.pull-right {
+    border-right-width: 1px;
+  }
+
+  small {
+    font-size: @font-size-small;
+    font-weight: 300;
+  }
+}
+
+// Tables =====================================================================
+
+table {
+  font-size: @font-size-small;
+}
+
+// Forms ======================================================================
+
+label,
+.control-label,
+.help-block,
+.checkbox,
+.radio {
+  font-size: @font-size-small;
+  font-weight: normal;
+}
+
+input[type="radio"],
+input[type="checkbox"] {
+  margin-top: 1px;
+}
+
+// Navs =======================================================================
+
+.nav {
+  .open > a,
+  .open > a:hover,
+  .open > a:focus {
+    border-color: transparent;
+  }
+}
+
+.nav-tabs {
+  > li > a {
+    background-color: @btn-default-bg;
+    color: @text-color;
+  }
+
+  .caret {
+    border-top-color: @text-color;
+    border-bottom-color: @text-color;
+  }
+}
+
+.nav-pills {
+  font-weight: 300;
+}
+
+.breadcrumb {
+  border: 1px solid @table-border-color;
+  border-radius: 3px;
+  font-size: 10px;
+  font-weight: 300;
+  text-transform: uppercase;
+}
+
+.pagination {
+  font-size: @font-size-small;
+  font-weight: 300;
+  color: @gray-light;
+
+  > li {
+    > a,
+    > span {
+      margin-left: 4px;
+      color: @gray-light;
+    }
+  }
+
+  > .active {
+    > a,
+    > span {
+      color: #fff;
+    }
+  }
+
+  > li,
+  > li:first-child,
+  > li:last-child {
+    > a,
+    > span {
+      border-radius: 3px;
+    }
+  }
+
+  &-lg > li > a {
+    padding-left: 22px;
+    padding-right: 22px;
+  }
+
+  &-sm > li > a {
+    padding: 0 5px;
+  }
+}
+
+.pager {
+  font-size: @font-size-small;
+  font-weight: 300;
+  color: @gray-light;
+}
+
+.list-group {
+  font-size: @font-size-small;
+  font-weight: 300;
+}
+
+// Indicators =================================================================
+
+.close {
+  opacity: 0.4;
+  text-decoration: none;
+  text-shadow: none;
+
+  &:hover,
+  &:focus {
+    opacity: 1;
+  }
+}
+
+.alert {
+  font-size: @font-size-small;
+  font-weight: 300;
+
+  .alert-link {
+    font-weight: normal;
+    color: #fff;
+    text-decoration: underline;
+  }
+}
+
+.label {
+  padding-left: 1em;
+  padding-right: 1em;
+  border-radius: 0;
+  font-weight: 300;
+
+  &-default {
+    background-color: @btn-default-bg;
+    color: @btn-default-color;
+  }
+}
+
+.badge {
+  font-weight: 300;
+}
+
+// Progress bars ==============================================================
+
+.progress {
+  height: 22px;
+  padding: 2px;
+  background-color: #f6f6f6;
+  border: 1px solid #ccc;
+  .box-shadow(none);
+}
+
+// Containers =================================================================
+
+.dropdown {
+
+  &-menu {
+    padding: 0;
+    margin-top: 0;
+    font-size: @font-size-small;
+
+    > li > a {
+      padding: 12px 15px;
+    }
+  }
+
+  &-header {
+    padding-left: 15px;
+    padding-right: 15px;
+    font-size: 9px;
+    text-transform: uppercase;
+  }
+}
+
+.popover {
+  color: #fff;
+  font-size: 12px;
+  font-weight: 300;
+}
+
+.panel {
+  &-heading,
+  &-footer {
+    border-top-right-radius: 0;
+    border-top-left-radius: 0;
+  }
+
+  &-default {
+    .close {
+      color: @text-color;
+    }
+  }
+}
+
+.modal {
+  .close {
+    color: @text-color;
+  }
+}
diff --git a/searx/static/less/bootstrap/theme_yeti/variables.less b/searx/static/less/bootstrap/theme_yeti/variables.less
new file mode 100644
index 000000000..af51f2f42
--- /dev/null
+++ b/searx/static/less/bootstrap/theme_yeti/variables.less
@@ -0,0 +1,856 @@
+// Yeti 3.3.1
+// Variables
+// --------------------------------------------------
+
+
+//== Colors
+//
+//## Gray and brand colors for use across Bootstrap.
+
+@gray-base:              #000;
+@gray-darker:            lighten(@gray-base, 13.5%); // #222
+@gray-dark:              lighten(@gray-base, 20%);   // #333
+@gray:                   #6f6f6f; // #555
+@gray-light:             lighten(@gray-base, 60%);   // #999
+@gray-lighter:           lighten(@gray-base, 93.5%); // #eee
+
+@brand-primary:         #008cba;
+@brand-success:         #43ac6a;
+@brand-info:            #5bc0de;
+@brand-warning:         #E99002;
+@brand-danger:          #F04124;
+
+
+//== Scaffolding
+//
+//## Settings for some of the most global styles.
+
+//** Background color for `<body>`.
+@body-bg:               #fff;
+//** Global text color on `<body>`.
+@text-color:            @gray-darker;
+
+//** Global textual link color.
+@link-color:            @brand-primary;
+//** Link hover color set via `darken()` function.
+@link-hover-color:      darken(@link-color, 15%);
+//** Link hover decoration.
+@link-hover-decoration: underline;
+
+
+//== Typography
+//
+//## Font, line-height, and color for body text, headings, and more.
+
+@font-family-sans-serif:  "Open Sans", "Helvetica Neue", Helvetica, Arial, sans-serif;
+@font-family-serif:       Georgia, "Times New Roman", Times, serif;
+//** Default monospace fonts for `<code>`, `<kbd>`, and `<pre>`.
+@font-family-monospace:   Menlo, Monaco, Consolas, "Courier New", monospace;
+@font-family-base:        @font-family-sans-serif;
+
+@font-size-base:          15px;
+@font-size-large:         ceil((@font-size-base * 1.25)); // ~18px
+@font-size-small:         12px; // ~12px
+
+@font-size-h1:            floor((@font-size-base * 2.6)); // ~36px
+@font-size-h2:            floor((@font-size-base * 2.15)); // ~30px
+@font-size-h3:            ceil((@font-size-base * 1.7)); // ~24px
+@font-size-h4:            ceil((@font-size-base * 1.25)); // ~18px
+@font-size-h5:            @font-size-base;
+@font-size-h6:            ceil((@font-size-base * 0.85)); // ~12px
+
+//** Unit-less `line-height` for use in components like buttons.
+@line-height-base:        1.4;
+//** Computed "line-height" (`font-size` * `line-height`) for use with `margin`, `padding`, etc.
+@line-height-computed:    floor((@font-size-base * @line-height-base)); // ~20px
+
+//** By default, this inherits from the `<body>`.
+@headings-font-family:    @font-family-base;
+@headings-font-weight:    300;
+@headings-line-height:    1.1;
+@headings-color:          inherit;
+
+
+//== Iconography
+//
+//## Specify custom location and filename of the included Glyphicons icon font. Useful for those including Bootstrap via Bower.
+
+//** Load fonts from this directory.
+@icon-font-path:          "../fonts/";
+//** File name for all font files.
+@icon-font-name:          "glyphicons-halflings-regular";
+//** Element ID within SVG icon file.
+@icon-font-svg-id:        "glyphicons_halflingsregular";
+
+
+//== Components
+//
+//## Define common padding and border radius sizes and more. Values based on 14px text and 1.428 line-height (~20px to start).
+
+@padding-base-vertical:     8px;
+@padding-base-horizontal:   12px;
+
+@padding-large-vertical:    16px;
+@padding-large-horizontal:  20px;
+
+@padding-small-vertical:    8px;
+@padding-small-horizontal:  12px;
+
+@padding-xs-vertical:       4px;
+@padding-xs-horizontal:     6px;
+
+@line-height-large:         1.33;
+@line-height-small:         1.5;
+
+@border-radius-base:        0;
+@border-radius-large:       0;
+@border-radius-small:       0;
+
+//** Global color for active items (e.g., navs or dropdowns).
+@component-active-color:    #fff;
+//** Global background color for active items (e.g., navs or dropdowns).
+@component-active-bg:       @brand-primary;
+
+//** Width of the `border` for generating carets that indicator dropdowns.
+@caret-width-base:          4px;
+//** Carets increase slightly in size for larger components.
+@caret-width-large:         5px;
+
+
+//== Tables
+//
+//## Customizes the `.table` component with basic values, each used across all table variations.
+
+//** Padding for `<th>`s and `<td>`s.
+@table-cell-padding:            8px;
+//** Padding for cells in `.table-condensed`.
+@table-condensed-cell-padding:  5px;
+
+//** Default background color used for all tables.
+@table-bg:                      transparent;
+//** Background color used for `.table-striped`.
+@table-bg-accent:               #f9f9f9;
+//** Background color used for `.table-hover`.
+@table-bg-hover:                #f5f5f5;
+@table-bg-active:               @table-bg-hover;
+
+//** Border color for table and cell borders.
+@table-border-color:            #ddd;
+
+
+//== Buttons
+//
+//## For each of Bootstrap's buttons, define text, background and border color.
+
+@btn-font-weight:                normal;
+
+@btn-default-color:              @gray-dark;
+@btn-default-bg:                 #e7e7e7;
+@btn-default-border:             #ccc;
+
+@btn-primary-color:              #fff;
+@btn-primary-bg:                 @brand-primary;
+@btn-primary-border:             darken(@btn-primary-bg, 5%);
+
+@btn-success-color:              #fff;
+@btn-success-bg:                 @brand-success;
+@btn-success-border:             darken(@btn-success-bg, 5%);
+
+@btn-info-color:                 #fff;
+@btn-info-bg:                    @brand-info;
+@btn-info-border:                darken(@btn-info-bg, 5%);
+
+@btn-warning-color:              #fff;
+@btn-warning-bg:                 @brand-warning;
+@btn-warning-border:             darken(@btn-warning-bg, 5%);
+
+@btn-danger-color:               #fff;
+@btn-danger-bg:                  @brand-danger;
+@btn-danger-border:              darken(@btn-danger-bg, 5%);
+
+@btn-link-disabled-color:        @gray-light;
+
+
+//== Forms
+//
+//##
+
+//** `<input>` background color
+@input-bg:                       #fff;
+//** `<input disabled>` background color
+@input-bg-disabled:              @gray-lighter;
+
+//** Text color for `<input>`s
+@input-color:                    @gray;
+//** `<input>` border color
+@input-border:                   #ccc;
+
+// TODO: Rename `@input-border-radius` to `@input-border-radius-base` in v4
+//** Default `.form-control` border radius
+@input-border-radius:            @border-radius-base;
+//** Large `.form-control` border radius
+@input-border-radius-large:      @border-radius-large;
+//** Small `.form-control` border radius
+@input-border-radius-small:      @border-radius-small;
+
+//** Border color for inputs on focus
+@input-border-focus:             #66afe9;
+
+//** Placeholder text color
+@input-color-placeholder:        @gray-light;
+
+//** Default `.form-control` height
+@input-height-base:              (@line-height-computed + (@padding-base-vertical * 2) + 2);
+//** Large `.form-control` height
+@input-height-large:             (ceil(@font-size-large * @line-height-large) + (@padding-large-vertical * 2) + 2);
+//** Small `.form-control` height
+@input-height-small:             (floor(@font-size-small * @line-height-small) + (@padding-small-vertical * 2) + 2);
+
+@legend-color:                   @gray-dark;
+@legend-border-color:            #e5e5e5;
+
+//** Background color for textual input addons
+@input-group-addon-bg:           @gray-lighter;
+//** Border color for textual input addons
+@input-group-addon-border-color: @input-border;
+
+//** Disabled cursor for form controls and buttons.
+@cursor-disabled:                not-allowed;
+
+
+//== Dropdowns
+//
+//## Dropdown menu container and contents.
+
+//** Background for the dropdown menu.
+@dropdown-bg:                    #fff;
+//** Dropdown menu `border-color`.
+@dropdown-border:                rgba(0,0,0,.15);
+//** Dropdown menu `border-color` **for IE8**.
+@dropdown-fallback-border:       #ccc;
+//** Divider color for between dropdown items.
+@dropdown-divider-bg:            rgba(0,0,0,.2);
+
+//** Dropdown link text color.
+@dropdown-link-color:            #555;
+//** Hover color for dropdown links.
+@dropdown-link-hover-color:      darken(@gray-dark, 5%);
+//** Hover background for dropdown links.
+@dropdown-link-hover-bg:         #eee;
+
+//** Active dropdown menu item text color.
+@dropdown-link-active-color:     @component-active-color;
+//** Active dropdown menu item background color.
+@dropdown-link-active-bg:        @component-active-bg;
+
+//** Disabled dropdown menu item background color.
+@dropdown-link-disabled-color:   @gray-light;
+
+//** Text color for headers within dropdown menus.
+@dropdown-header-color:          @gray-light;
+
+//** Deprecated `@dropdown-caret-color` as of v3.1.0
+@dropdown-caret-color:           #000;
+
+
+//-- Z-index master list
+//
+// Warning: Avoid customizing these values. They're used for a bird's eye view
+// of components dependent on the z-axis and are designed to all work together.
+//
+// Note: These variables are not generated into the Customizer.
+
+@zindex-navbar:            1000;
+@zindex-dropdown:          1000;
+@zindex-popover:           1060;
+@zindex-tooltip:           1070;
+@zindex-navbar-fixed:      1030;
+@zindex-modal:             1040;
+
+
+//== Media queries breakpoints
+//
+//## Define the breakpoints at which your layout will change, adapting to different screen sizes.
+
+// Extra small screen / phone
+//** Deprecated `@screen-xs` as of v3.0.1
+@screen-xs:                  480px;
+//** Deprecated `@screen-xs-min` as of v3.2.0
+@screen-xs-min:              @screen-xs;
+//** Deprecated `@screen-phone` as of v3.0.1
+@screen-phone:               @screen-xs-min;
+
+// Small screen / tablet
+//** Deprecated `@screen-sm` as of v3.0.1
+@screen-sm:                  768px;
+@screen-sm-min:              @screen-sm;
+//** Deprecated `@screen-tablet` as of v3.0.1
+@screen-tablet:              @screen-sm-min;
+
+// Medium screen / desktop
+//** Deprecated `@screen-md` as of v3.0.1
+@screen-md:                  992px;
+@screen-md-min:              @screen-md;
+//** Deprecated `@screen-desktop` as of v3.0.1
+@screen-desktop:             @screen-md-min;
+
+// Large screen / wide desktop
+//** Deprecated `@screen-lg` as of v3.0.1
+@screen-lg:                  1200px;
+@screen-lg-min:              @screen-lg;
+//** Deprecated `@screen-lg-desktop` as of v3.0.1
+@screen-lg-desktop:          @screen-lg-min;
+
+// So media queries don't overlap when required, provide a maximum
+@screen-xs-max:              (@screen-sm-min - 1);
+@screen-sm-max:              (@screen-md-min - 1);
+@screen-md-max:              (@screen-lg-min - 1);
+
+
+//== Grid system
+//
+//## Define your custom responsive grid.
+
+//** Number of columns in the grid.
+@grid-columns:              12;
+//** Padding between columns. Gets divided in half for the left and right.
+@grid-gutter-width:         30px;
+// Navbar collapse
+//** Point at which the navbar becomes uncollapsed.
+@grid-float-breakpoint:     @screen-sm-min;
+//** Point at which the navbar begins collapsing.
+@grid-float-breakpoint-max: (@grid-float-breakpoint - 1);
+
+
+//== Container sizes
+//
+//## Define the maximum width of `.container` for different screen sizes.
+
+// Small screen / tablet
+@container-tablet:             (720px + @grid-gutter-width);
+//** For `@screen-sm-min` and up.
+@container-sm:                 @container-tablet;
+
+// Medium screen / desktop
+@container-desktop:            (940px + @grid-gutter-width);
+//** For `@screen-md-min` and up.
+@container-md:                 @container-desktop;
+
+// Large screen / wide desktop
+@container-large-desktop:      (1140px + @grid-gutter-width);
+//** For `@screen-lg-min` and up.
+@container-lg:                 @container-large-desktop;
+
+
+//== Navbar
+//
+//##
+
+// Basics of a navbar
+@navbar-height:                    45px;
+@navbar-margin-bottom:             @line-height-computed;
+@navbar-border-radius:             @border-radius-base;
+@navbar-padding-horizontal:        floor((@grid-gutter-width / 2));
+@navbar-padding-vertical:          ((@navbar-height - @line-height-computed) / 2);
+@navbar-collapse-max-height:       340px;
+
+@navbar-default-color:             #fff;
+@navbar-default-bg:                @gray-dark;
+@navbar-default-border:            darken(@navbar-default-bg, 6.5%);
+
+// Navbar links
+@navbar-default-link-color:                #fff;
+@navbar-default-link-hover-color:          #fff;
+@navbar-default-link-hover-bg:             #272727;
+@navbar-default-link-active-color:         #fff;
+@navbar-default-link-active-bg:            #272727;
+@navbar-default-link-disabled-color:       #ccc;
+@navbar-default-link-disabled-bg:          transparent;
+
+// Navbar brand label
+@navbar-default-brand-color:               @navbar-default-link-color;
+@navbar-default-brand-hover-color:         @navbar-default-brand-color;
+@navbar-default-brand-hover-bg:            transparent;
+
+// Navbar toggle
+@navbar-default-toggle-hover-bg:           transparent;
+@navbar-default-toggle-icon-bar-bg:        #fff;
+@navbar-default-toggle-border-color:       transparent;
+
+
+// Inverted navbar
+// Reset inverted navbar basics
+@navbar-inverse-color:                      #fff;
+@navbar-inverse-bg:                         @brand-primary;
+@navbar-inverse-border:                     darken(@navbar-inverse-bg, 10%);
+
+// Inverted navbar links
+@navbar-inverse-link-color:                 #fff;
+@navbar-inverse-link-hover-color:           #fff;
+@navbar-inverse-link-hover-bg:              darken(@navbar-inverse-bg, 10%);
+@navbar-inverse-link-active-color:          #fff;
+@navbar-inverse-link-active-bg:             darken(@navbar-inverse-bg, 10%);
+@navbar-inverse-link-disabled-color:        #444;
+@navbar-inverse-link-disabled-bg:           transparent;
+
+// Inverted navbar brand label
+@navbar-inverse-brand-color:                @navbar-inverse-link-color;
+@navbar-inverse-brand-hover-color:          #fff;
+@navbar-inverse-brand-hover-bg:             transparent;
+
+// Inverted navbar toggle
+@navbar-inverse-toggle-hover-bg:            transparent;
+@navbar-inverse-toggle-icon-bar-bg:         #fff;
+@navbar-inverse-toggle-border-color:        transparent;
+
+
+//== Navs
+//
+//##
+
+//=== Shared nav styles
+@nav-link-padding:                          10px 15px;
+@nav-link-hover-bg:                         @gray-lighter;
+
+@nav-disabled-link-color:                   @gray-light;
+@nav-disabled-link-hover-color:             @gray-light;
+
+//== Tabs
+@nav-tabs-border-color:                     @table-border-color;
+
+@nav-tabs-link-hover-border-color:          @gray-lighter;
+
+@nav-tabs-active-link-hover-bg:             @body-bg;
+@nav-tabs-active-link-hover-color:          @gray;
+@nav-tabs-active-link-hover-border-color:   @table-border-color;
+
+@nav-tabs-justified-link-border-color:            @table-border-color;
+@nav-tabs-justified-active-link-border-color:     @body-bg;
+
+//== Pills
+@nav-pills-border-radius:                   @border-radius-base;
+@nav-pills-active-link-hover-bg:            @component-active-bg;
+@nav-pills-active-link-hover-color:         @component-active-color;
+
+
+//== Pagination
+//
+//##
+
+@pagination-color:                     @link-color;
+@pagination-bg:                        transparent;
+@pagination-border:                    transparent;
+
+@pagination-hover-color:               @link-hover-color;
+@pagination-hover-bg:                  @gray-lighter;
+@pagination-hover-border:              transparent;
+
+@pagination-active-color:              #fff;
+@pagination-active-bg:                 @brand-primary;
+@pagination-active-border:             transparent;
+
+@pagination-disabled-color:            @gray-light;
+@pagination-disabled-bg:               #fff;
+@pagination-disabled-border:           transparent;
+
+
+//== Pager
+//
+//##
+
+@pager-bg:                             @pagination-bg;
+@pager-border:                         @pagination-border;
+@pager-border-radius:                  3px;
+
+@pager-hover-bg:                       @pagination-hover-bg;
+
+@pager-active-bg:                      @pagination-active-bg;
+@pager-active-color:                   @pagination-active-color;
+
+@pager-disabled-color:                 @gray-light;
+
+
+//== Jumbotron
+//
+//##
+
+@jumbotron-padding:              30px;
+@jumbotron-color:                inherit;
+@jumbotron-bg:                   #fafafa;
+@jumbotron-heading-color:        inherit;
+@jumbotron-font-size:            ceil((@font-size-base * 1.5));
+
+
+//== Form states and alerts
+//
+//## Define colors for form feedback states and, by default, alerts.
+
+@state-success-text:             @brand-success;
+@state-success-bg:               #dff0d8;
+@state-success-border:           darken(@state-success-text, 5%);
+
+@state-info-text:                @brand-info;
+@state-info-bg:                  #d9edf7;
+@state-info-border:              darken(@state-info-text, 7%);
+
+@state-warning-text:             @brand-warning;
+@state-warning-bg:               #fcf8e3;
+@state-warning-border:           darken(@state-warning-text, 5%);
+
+@state-danger-text:              @brand-danger;
+@state-danger-bg:                #f2dede;
+@state-danger-border:            darken(@state-danger-text, 5%);
+
+
+//== Tooltips
+//
+//##
+
+//** Tooltip max width
+@tooltip-max-width:           200px;
+//** Tooltip text color
+@tooltip-color:               #fff;
+//** Tooltip background color
+@tooltip-bg:                  @gray-dark;
+@tooltip-opacity:             .9;
+
+//** Tooltip arrow width
+@tooltip-arrow-width:         5px;
+//** Tooltip arrow color
+@tooltip-arrow-color:         @tooltip-bg;
+
+
+//== Popovers
+//
+//##
+
+//** Popover body background color
+@popover-bg:                          @gray-dark;
+//** Popover maximum width
+@popover-max-width:                   276px;
+//** Popover border color
+@popover-border-color:                transparent;
+//** Popover fallback border color
+@popover-fallback-border-color:       @gray-dark;
+
+//** Popover title background color
+@popover-title-bg:                    @popover-bg;
+
+//** Popover arrow width
+@popover-arrow-width:                 10px;
+//** Popover arrow color
+@popover-arrow-color:                 @popover-bg;
+
+//** Popover outer arrow width
+@popover-arrow-outer-width:           (@popover-arrow-width + 1);
+//** Popover outer arrow color
+@popover-arrow-outer-color:           fadein(@popover-border-color, 5%);
+//** Popover outer arrow fallback color
+@popover-arrow-outer-fallback-color:  darken(@popover-fallback-border-color, 20%);
+
+
+//== Labels
+//
+//##
+
+//** Default label background color
+@label-default-bg:            @gray-light;
+//** Primary label background color
+@label-primary-bg:            @brand-primary;
+//** Success label background color
+@label-success-bg:            @brand-success;
+//** Info label background color
+@label-info-bg:               @brand-info;
+//** Warning label background color
+@label-warning-bg:            @brand-warning;
+//** Danger label background color
+@label-danger-bg:             @brand-danger;
+
+//** Default label text color
+@label-color:                 #fff;
+//** Default text color of a linked label
+@label-link-hover-color:      #fff;
+
+
+//== Modals
+//
+//##
+
+//** Padding applied to the modal body
+@modal-inner-padding:         20px;
+
+//** Padding applied to the modal title
+@modal-title-padding:         15px;
+//** Modal title line-height
+@modal-title-line-height:     @line-height-base;
+
+//** Background color of modal content area
+@modal-content-bg:                             #fff;
+//** Modal content border color
+@modal-content-border-color:                   rgba(0,0,0,.2);
+//** Modal content border color **for IE8**
+@modal-content-fallback-border-color:          #999;
+
+//** Modal backdrop background color
+@modal-backdrop-bg:           #000;
+//** Modal backdrop opacity
+@modal-backdrop-opacity:      .5;
+//** Modal header border color
+@modal-header-border-color:   #e5e5e5;
+//** Modal footer border color
+@modal-footer-border-color:   @modal-header-border-color;
+
+@modal-lg:                    900px;
+@modal-md:                    600px;
+@modal-sm:                    300px;
+
+
+//== Alerts
+//
+//## Define alert colors, border radius, and padding.
+
+@alert-padding:               15px;
+@alert-border-radius:         @border-radius-base;
+@alert-link-font-weight:      bold;
+
+@alert-success-bg:            @brand-success;
+@alert-success-text:          #fff;
+@alert-success-border:        @state-success-border;
+
+@alert-info-bg:               @brand-info;
+@alert-info-text:             #fff;
+@alert-info-border:           @state-info-border;
+
+@alert-warning-bg:            @brand-warning;
+@alert-warning-text:          #fff;
+@alert-warning-border:        @state-warning-border;
+
+@alert-danger-bg:             @brand-danger;
+@alert-danger-text:           #fff;
+@alert-danger-border:         @state-danger-border;
+
+
+//== Progress bars
+//
+//##
+
+//** Background color of the whole progress component
+@progress-bg:                 #f5f5f5;
+//** Progress bar text color
+@progress-bar-color:          #fff;
+//** Variable for setting rounded corners on progress bar.
+@progress-border-radius:      @border-radius-base;
+
+//** Default progress bar color
+@progress-bar-bg:             @brand-primary;
+//** Success progress bar color
+@progress-bar-success-bg:     @brand-success;
+//** Warning progress bar color
+@progress-bar-warning-bg:     @brand-warning;
+//** Danger progress bar color
+@progress-bar-danger-bg:      @brand-danger;
+//** Info progress bar color
+@progress-bar-info-bg:        @brand-info;
+
+
+//== List group
+//
+//##
+
+//** Background color on `.list-group-item`
+@list-group-bg:                 #fff;
+//** `.list-group-item` border color
+@list-group-border:             @table-border-color;
+//** List group border radius
+@list-group-border-radius:      @border-radius-base;
+
+//** Background color of single list items on hover
+@list-group-hover-bg:           #f5f5f5;
+//** Text color of active list items
+@list-group-active-color:       @component-active-color;
+//** Background color of active list items
+@list-group-active-bg:          @component-active-bg;
+//** Border color of active list elements
+@list-group-active-border:      @list-group-active-bg;
+//** Text color for content within active list items
+@list-group-active-text-color:  lighten(@list-group-active-bg, 40%);
+
+//** Text color of disabled list items
+@list-group-disabled-color:      @gray-light;
+//** Background color of disabled list items
+@list-group-disabled-bg:         @gray-lighter;
+//** Text color for content within disabled list items
+@list-group-disabled-text-color: @list-group-disabled-color;
+
+@list-group-link-color:         #555;
+@list-group-link-hover-color:   @list-group-link-color;
+@list-group-link-heading-color: #333;
+
+
+//== Panels
+//
+//##
+
+@panel-bg:                    #fff;
+@panel-body-padding:          15px;
+@panel-heading-padding:       10px 15px;
+@panel-footer-padding:        @panel-heading-padding;
+@panel-border-radius:         @border-radius-base;
+
+//** Border color for elements within panels
+@panel-inner-border:          @table-border-color;
+@panel-footer-bg:             #f5f5f5;
+
+@panel-default-text:          @gray-dark;
+@panel-default-border:        @table-border-color;
+@panel-default-heading-bg:    #f5f5f5;
+
+@panel-primary-text:          #fff;
+@panel-primary-border:        @brand-primary;
+@panel-primary-heading-bg:    @brand-primary;
+
+@panel-success-text:          #fff;
+@panel-success-border:        @state-success-border;
+@panel-success-heading-bg:    @brand-success;
+
+@panel-info-text:             #fff;
+@panel-info-border:           @state-info-border;
+@panel-info-heading-bg:       @brand-info;
+
+@panel-warning-text:          #fff;
+@panel-warning-border:        @state-warning-border;
+@panel-warning-heading-bg:    @brand-warning;
+
+@panel-danger-text:           #fff;
+@panel-danger-border:         @state-danger-border;
+@panel-danger-heading-bg:     @brand-danger;
+
+
+//== Thumbnails
+//
+//##
+
+//** Padding around the thumbnail image
+@thumbnail-padding:           4px;
+//** Thumbnail background color
+@thumbnail-bg:                @body-bg;
+//** Thumbnail border color
+@thumbnail-border:            @table-border-color;
+//** Thumbnail border radius
+@thumbnail-border-radius:     @border-radius-base;
+
+//** Custom text color for thumbnail captions
+@thumbnail-caption-color:     @text-color;
+//** Padding around the thumbnail caption
+@thumbnail-caption-padding:   9px;
+
+
+//== Wells
+//
+//##
+
+@well-bg:                     @jumbotron-bg;
+@well-border:                 darken(@well-bg, 7%);
+
+
+//== Badges
+//
+//##
+
+@badge-color:                 #fff;
+//** Linked badge text color on hover
+@badge-link-hover-color:      #fff;
+@badge-bg:                    @btn-primary-bg;
+
+//** Badge text color in active nav link
+@badge-active-color:          @link-color;
+//** Badge background color in active nav link
+@badge-active-bg:             #fff;
+
+@badge-font-weight:           bold;
+@badge-line-height:           1;
+@badge-border-radius:         10px;
+
+
+//== Breadcrumbs
+//
+//##
+
+@breadcrumb-padding-vertical:   8px;
+@breadcrumb-padding-horizontal: 15px;
+//** Breadcrumb background color
+@breadcrumb-bg:                 #f5f5f5;
+//** Breadcrumb text color
+@breadcrumb-color:              @gray-light;
+//** Text color of current page in the breadcrumb
+@breadcrumb-active-color:       @gray-dark;
+//** Textual separator for between breadcrumb elements
+@breadcrumb-separator:          "/";
+
+
+//== Carousel
+//
+//##
+
+@carousel-text-shadow:                        0 1px 2px rgba(0,0,0,.6);
+
+@carousel-control-color:                      #fff;
+@carousel-control-width:                      15%;
+@carousel-control-opacity:                    .5;
+@carousel-control-font-size:                  20px;
+
+@carousel-indicator-active-bg:                #fff;
+@carousel-indicator-border-color:             #fff;
+
+@carousel-caption-color:                      #fff;
+
+
+//== Close
+//
+//##
+
+@close-font-weight:           bold;
+@close-color:                 #fff;
+@close-text-shadow:           0 1px 0 #fff;
+
+
+//== Code
+//
+//##
+
+@code-color:                  #c7254e;
+@code-bg:                     #f9f2f4;
+
+@kbd-color:                   #fff;
+@kbd-bg:                      #333;
+
+@pre-bg:                      #f5f5f5;
+@pre-color:                   @gray-dark;
+@pre-border-color:            #ccc;
+@pre-scrollable-max-height:   340px;
+
+
+//== Type
+//
+//##
+
+//** Horizontal offset for forms and lists.
+@component-offset-horizontal: 180px;
+//** Text muted color
+@text-muted:                  @gray-light;
+//** Abbreviations and acronyms border color
+@abbr-border-color:           @gray-light;
+//** Headings small color
+@headings-small-color:        @gray-light;
+//** Blockquote small color
+@blockquote-small-color:      @gray;
+//** Blockquote font size
+@blockquote-font-size:        (@font-size-base * 1.25);
+//** Blockquote border color
+@blockquote-border-color:     @table-border-color;
+//** Page header border color
+@page-header-border-color:    @table-border-color;
+//** Width of horizontal description list titles
+@dl-horizontal-offset:        @component-offset-horizontal;
+//** Horizontal line color.
+@hr-border:                   @table-border-color;
diff --git a/searx/templates/oscar/base.html b/searx/templates/oscar/base.html
index 42cd4e9a7..c39de0460 100644
--- a/searx/templates/oscar/base.html
+++ b/searx/templates/oscar/base.html
@@ -10,7 +10,11 @@
     {% block meta %}{% endblock %}
     <title>{% block title %}{% endblock %}searx</title>
     
-    <link rel="stylesheet" href="{{ url_for('static', filename='css/bootstrap.min.css') }}" type="text/css" />
+    {% if bootstrap_theme == 'default' %}
+        <link rel="stylesheet" href="{{ url_for('static', filename='css/bootstrap.min.css') }}" type="text/css" />
+    {% else %}
+        <link rel="stylesheet" href="{{ url_for('static', filename='css/bootstrap.' + bootstrap_theme + '.min.css') }}" type="text/css" />
+    {% endif %}
     <link rel="stylesheet" href="{{ url_for('static', filename='css/oscar.min.css') }}" type="text/css" />  
     <link rel="stylesheet" href="{{ url_for('static', filename='css/leaflet.min.css') }}" type="text/css" />
 
diff --git a/searx/templates/oscar/preferences.html b/searx/templates/oscar/preferences.html
index 1a885f6cc..352c7d551 100644
--- a/searx/templates/oscar/preferences.html
+++ b/searx/templates/oscar/preferences.html
@@ -9,6 +9,7 @@
     <!-- Nav tabs -->
     <ul class="nav nav-tabs hide_if_nojs" role="tablist" style="margin-bottom:20px;">
       <li class="active"><a href="#tab_general" role="tab" data-toggle="tab">{{ _('General') }}</a></li>
+      <li><a href="#tab_template" role="tab" data-toggle="tab">{{ _('Template features') }}</a></li>
       <li><a href="#tab_engine" role="tab" data-toggle="tab">{{ _('Engines') }}</a></li>
     </ul>
 
@@ -96,6 +97,28 @@
             </div>
             </fieldset>
         </div>
+        
+        <div class="tab-pane active_if_nojs" id="tab_template">
+            <noscript>
+                <h3>{{ _('Template features') }}</h3>
+            </noscript>
+        
+            <fieldset>
+            <div class="container-fluid">
+                <div class="row form-group">
+                    <label class="col-sm-3 col-md-2">{{ _('bootstrap theme') }}</label>
+                    <div class="col-sm-4 col-md-4">
+                        <select class="form-control" name='bootstrap_theme'>
+                            {% for b_theme in bootstrap_themes %}
+                                <option value="{{ b_theme }}" {% if bootstrap_theme == b_theme %}selected="selected"{% endif %}>{{ b_theme }}</option>
+                            {% endfor %}
+                        </select>
+                    </div>
+                    <span class="col-sm-5 col-md-6 help-block">{{ _('Change style of this layout') }}</span>
+                </div>
+            </div>
+            </fieldset>
+        </div>
         <div class="tab-pane active_if_nojs" id="tab_engine">
 
             <!-- Nav tabs -->
diff --git a/searx/webapp.py b/searx/webapp.py
index e25156f40..483b367d9 100644
--- a/searx/webapp.py
+++ b/searx/webapp.py
@@ -261,6 +261,9 @@ def render(template_name, override_theme=None, **kwargs):
 
     if 'autocomplete' not in kwargs:
         kwargs['autocomplete'] = autocomplete
+    
+    if 'bootstrap_theme' not in kwargs:
+        kwargs['bootstrap_theme'] = request.cookies.get('bootstrap_theme', 'default')
 
     kwargs['searx_version'] = VERSION_STRING
 
@@ -464,6 +467,7 @@ def preferences():
     Settings that are going to be saved as cookies."""
     lang = None
     image_proxy = request.cookies.get('image_proxy', settings['server'].get('image_proxy'))
+    bootstrap_themes = ['default', 'simplex', 'yeti', 'readable']
 
     if request.cookies.get('language')\
        and request.cookies['language'] in (x[0] for x in language_codes):
@@ -478,6 +482,7 @@ def preferences():
         locale = None
         autocomplete = ''
         method = 'POST'
+        bootstrap_theme = None
         for pd_name, pd in request.form.items():
             if pd_name.startswith('category_'):
                 category = pd_name[9:]
@@ -502,6 +507,11 @@ def preferences():
                     blocked_engines.append(engine_name)
             elif pd_name == 'theme':
                 theme = pd if pd in themes else default_theme
+            elif pd_name == 'bootstrap_theme':
+                if pd in bootstrap_themes:
+                    bootstrap_theme = pd
+                else:
+                    bootstrap_theme = 'default'
 
         resp = make_response(redirect(url_for('index')))
 
@@ -543,6 +553,9 @@ def preferences():
 
         resp.set_cookie('theme', theme, max_age=cookie_max_age)
 
+        if bootstrap_theme:
+            resp.set_cookie('bootstrap_theme', bootstrap_theme, max_age=cookie_max_age)
+
         return resp
     return render('preferences.html',
                   locales=settings['locales'],
@@ -555,6 +568,7 @@ def preferences():
                   autocomplete_backends=autocomplete_backends,
                   shortcuts={y: x for x, y in engine_shortcuts.items()},
                   themes=themes,
+                  bootstrap_themes=bootstrap_themes,
                   theme=get_current_theme_name())