wagtail/client/src/components/Sidebar/menu/MenuItem.scss

// stylelint-disable declaration-no-important
.sidebar-menu-item {
  $root: &;
  @include transition(border-color $menu-transition-duration ease);
  position: relative;

  &__link {
    @apply w-text-14;
    @include transition(
      border-color $menu-transition-duration ease,
      background-color $menu-transition-duration ease
    );
    position: relative;
    display: block;
    width: 100%;
    box-sizing: border-box;
    white-space: nowrap;
    border-inline-start: 3px solid transparent;
    -webkit-font-smoothing: auto;
    border: 0;
    background: transparent;
    text-align: start;
    color: $color-menu-text;
    padding: 11px 20px;
    font-weight: 400;

    // Note, font-weights lower than normal,
    // and font-size smaller than 1em (80% ~= 12.8px),
    // makes the strokes thinner than 1px on non-retina screens
    // making the text semi-transparent
    &:hover,
    &:focus {
      color: $color-white;
      text-shadow: -1px -1px 0 rgba(0, 0, 0, 0.3);
    }

    &:before {
      font-size: 1rem;
      vertical-align: -15%;
      margin-inline-end: 0.5em;
    }

    // only really used for spinners and settings menu
    &:after {
      font-size: 1.5em;
      margin: 0;
      position: absolute;
      // Remove once we drop support for Safari 13.
      // stylelint-disable-next-line property-disallowed-list
      right: 0.5em;
      inset-inline-end: 0.5em;
      top: 0.5em;
      margin-top: 0;
    }

    // Disable icon margin, this is instead applied to the left of the .menuitem-label
    // This is because SVG icons and legacy icons apply this margin differently,
    // we could remove this override when we remove legacy icons
    .icon {
      margin-inline-end: 0 !important;
    }
  }

  &--in-sub-menu {
    @apply hover:w-bg-primary;

    #{$root}__link {
      // Links inside a submenu should have normal wrapping
      white-space: normal;
    }
  }

  &--active {
    @apply w-bg-primary-200;
    text-shadow: -1px -1px 0 rgba(0, 0, 0, 0.3);

    > a {
      border-inline-start-color: $color-salmon;
      color: $color-white;
    }
  }
}

.menuitem-label {
  @include transition(opacity $menu-transition-duration ease);
  margin-inline-start: 0.5em;
}

.sidebar--slim {
  .sidebar-menu-item {
    .menuitem-label {
      opacity: 0;
    }
  }

  .sidebar-menu-item--in-sub-menu {
    .menuitem-label {
      opacity: 1;
    }
  }
}