resources/src/mediawiki.ui/components/checkbox.less

   1 @import "mediawiki.mixins";
   2
   3 // Checkbox
   4 //
   5 // Styling checkboxes in a way that works cross browser is a tricky problem to solve.
   6 // In MediaWiki UI we wrap a checkbox and label inside mw-ui-checkbox
   7 // This renders in all browsers except IE6-8 which do not support the :checked selector
   8 // these are kept backwards compatible using the :not(#noop) selector
   9 // Ensure to markup the checkbox and label with id and for attributes respectively
  10 //
  11 // Markup:
  12 // <div class="mw-ui-checkbox">
  13 //   <input type="checkbox" id="kss-example-5"><label for="kss-example-5">Standard checkbox</label>
  14 // </div>
  15 // <div class="mw-ui-checkbox">
  16 //   <input type="checkbox" id="kss-example-5-2" disabled><label for="kss-example-5-2">Disabled checkbox</label>
  17 // </div>
  18 //
  19 // Styleguide 5.
  20 .mw-ui-checkbox {
  21         display: inline-block;
  22         vertical-align: middle;
  23 }
  24
  25 @checkboxSize: 24px;
  26
  27 // We use the not selector to cancel out styling on IE 8 and below
  28 .mw-ui-checkbox:not(#noop) {
  29         // Position relatively so we can make use of absolute pseudo elements
  30         position: relative;
  31         line-height: @checkboxSize;
  32
  33         * {
  34                 vertical-align: middle;
  35         }
  36
  37         input[type="checkbox"] {
  38                 // we hide the input element as instead we will style the label that follows
  39                 // we use opacity so that VoiceOver software can still identify it
  40                 opacity: 0;
  41                 // ensure the invisible checkbox takes up the required width
  42                 width: @checkboxSize;
  43                 height: @checkboxSize;
  44
  45                 // the pseudo before element of the label after the checkbox now looks like a checkbox
  46                 & + label {
  47                         &::before {
  48                                                 content: '';
  49                                                 position: absolute;
  50                                                 left: 0;
  51                                                 display: inline-block;
  52                                                 border-radius: 2px;
  53                                                 margin-right: 18px;
  54                                                 width: @checkboxSize;
  55                                                 height: @checkboxSize;
  56                                                 background-color: #fff;
  57                                                 cursor: pointer;
  58                                                 border: 1px solid grey;
  59                                         }
  60                 }
  61
  62                 // when the input is checked, style the label pseudo before element that followed as a checked checkbox
  63                 &:checked {
  64                         + label {
  65                                 &::before {
  66                                         .background-image-svg('images/checked.svg', 'images/checked.png');
  67                                         background-repeat: no-repeat;
  68                                         background-position: center top;
  69                                 }
  70                         }
  71                 }
  72
  73                 @focusBottomBorderSize: 3px;
  74                 &:active,
  75                 &:focus {
  76                         + label {
  77                                 &::after {
  78                                         content: '';
  79                                         position: absolute;
  80                                         width: @checkboxSize;
  81                                         height: @checkboxSize - @focusBottomBorderSize + 1; // offset by bottom border
  82                                         // offset from the checkbox by 1px to account for left border
  83                                         left: 1px;
  84                                         border-bottom: solid @focusBottomBorderSize lightgrey;
  85                                 }
  86                         }
  87                 }
  88
  89                 // disabled checked boxes have a gray background
  90                 &:disabled + label::before {
  91                         background-color: lightgrey;
  92                 }
  93         }
  94 }