argos/dmp-frontend/src/assets/scss/core/_dropdown.scss

// Menus https://www.google.com/design/spec/components/menus.html#menus-specs
// Dropdown buttons (mobile and desktop) https://www.google.com/design/spec/components/buttons.html#buttons-dropdown-buttons

.dropdown-menu {
  display: none;
  padding: $bmd-dropdown-margin-y 0;
  border: 0;
  opacity: 0;
  transform: scale(0);
  transform-origin: 0 0;
  will-change: transform, opacity;
  transition: transform $bmd-menu-expand-duration $bmd-animation-curve-default,
              opacity $bmd-menu-fade-duration $bmd-animation-curve-default;
  box-shadow: 0 2px 5px 0 rgba(0, 0, 0, 0.26);

  &.showing {
    animation-name: bmd-dropdown-animation;
    animation-duration: $bmd-menu-expand-duration;
    animation-fill-mode: forwards;
    animation-timing-function: $bmd-animation-curve-default;
  }

  .open > &,
  &.show {
    display: block;
    opacity: 1;
    transform: scale(1);
  }

  &.hiding {
    display: block;
    opacity: 0;
    transform: scale(0);
  }

  &[x-placement="bottom-start"] {
    transform-origin: 0 0;
  }

  &[x-placement="bottom-end"] {
    transform-origin: 100% 0;
  }

  &[x-placement="top-start"] {
    transform-origin: 0 100%;
  }

  &[x-placement="top-end"] {
    transform-origin: 100% 100%;
  }

  .disabled > a{
        color: $bmd-dropdown-header-color;

        &:focus,
        &:hover{
            text-decoration: none;
            background-color: transparent;
            background-image: none;
            color: $bmd-dropdown-header-color;
        }
    }

    &.dropdown-with-icons .dropdown-item{
        padding: $dropdown-item-padding-y + 0.125 $dropdown-item-padding-x $dropdown-item-padding-y + 0.125 $dropdown-item-padding-y + 0.125;

        & .material-icons{
            vertical-align: middle;
            font-size: 24px;
            position: relative;
            margin-top: -4px;
            top: 1px;
            margin-right: 12px;
            opacity: .5;
        }
    }


  // https://www.google.com/design/spec/components/menus.html#menus-specs
  .dropdown-item,
  li > a{    // used to properly size the ripple container
    position: relative;
    width: auto;

    display: flex;
    flex-flow: nowrap;
    align-items: center;
    color: $bmd-dropdown-link-color;
    font-weight: normal;
    text-decoration: none;

    font-size: .8125rem;
    border-radius: math.div($border-radius, 2);
    margin: 0 $bmd-dropdown-margin-y;
    @include transitions($fast-transition-time, $transition-linear);

    min-width: $bmd-menu-item-min-width;

    padding: $dropdown-item-padding-y  $dropdown-item-padding-x;

    overflow: hidden;
    line-height: $bmd-line-height;
    text-overflow: ellipsis;
    word-wrap: break-word;

    @include media-breakpoint-up(md) {
      padding-right: $bmd-menu-item-padding-right-md;
      padding-left: $bmd-menu-item-padding-left-md;
    }
  }

  .dropdown-item:hover,
  .dropdown-item:focus,
  a:hover,
  a:focus,
  a:active {
    @include shadow-small-color($brand-primary);
    background-color: $brand-primary;
    color: #FFFFFF;
  }
}

// this could be in a .btn-group or .dropdown
.dropdown-toggle {
  &.bmd-btn-icon,
  &.bmd-btn-fab {
    // remove the dropdown icon
    &::after {
      display: none;
    }

    ~ .dropdown-menu {
      &.dropdown-menu-top-left,
      &.dropdown-menu-top-right {
        bottom: $bmd-btn-icon-size; // push up the bottom of the menu the height of the button
      }
    }
  }

  &:after{
      will-change: transform;
      transition: transform $bmd-animation-dropdown-caret linear;
  }

  .show &:after{
    @include rotate-180();
  }

  &.bmd-btn-fab-sm {
    ~ .dropdown-menu {
      &.dropdown-menu-top-left,
      &.dropdown-menu-top-right {
        bottom: $bmd-btn-fab-size-sm; // push up the bottom of the menu the height of the button
      }
    }
  }

  &.bmd-btn-icon {
    ~ .dropdown-menu {
      // collapse some spacing
      margin: 0;
    }
  }
}

.dropdown-header{
    font-size: 0.75rem;
    padding-top: $dropdown-header-padding-y;
    padding-bottom: $dropdown-header-padding-y;
    text-transform: none;
    color: $bmd-dropdown-header-color;
    line-height: $bmd-line-height;
    font-weight: inherit;
}

@keyframes bmd-dropdown-animation {
  from {
    opacity: 0;
    transform: scale(0);
  }
  to {
    opacity: 1;
    transform: scale(1);
  }
}

.dropdown-menu.bootstrap-datetimepicker-widget{
    opacity: 0;
    transform: scale(0);
    transition-duration: $bmd-menu-expand-duration;
    transition-timing-function: $bmd-animation-curve-default;
    transform-origin: 0 0;
    will-change: transform, opacity;
    top: 0;
}

.dropdown-menu.bootstrap-datetimepicker-widget.top{
    transform-origin: 0 100%;
}

.dropdown-menu.bootstrap-datetimepicker-widget.open{
    opacity: 1;
    transform: scale(1);
    top: 0;
}