amis/scss/components/form/_nested-select.scss

.#{$ns}NestedSelect {
  display: inline-flex;
  vertical-align: middle;
  outline: none;
  position: relative;
  border: var(--Form-select-borderWidth) solid var(--Form-select-borderColor);
  background: var(--Form-select-bg);
  border-radius: var(--Form-select-borderRadius);
  min-height: var(--Form-selectOption-height);
  $paddingY: calc(
    (
        var(--Form-selectOption-height) - var(--Form-input-lineHeight) *
          var(--Form-input-fontSize) - var(--Form-select-borderWidth) * 2
      ) / 2
  );
  padding: $paddingY 0 $paddingY var(--Form-select-paddingX);
  cursor: pointer;
  color: var(--Form-select-color);

  &.is-disabled {
    color: var(--text--muted-color);
    background: var(--Form-input-onDisabled-bg);
    border-color: var(--Form-input-onDisabled-borderColor);
  }

  &.is-focused,
  &.is-opened {
    border-color: var(--Form-input-onFocused-borderColor);
    // border-bottom: 0;
    color: var(--Form-select-onFocused-color);
  }

  &.is-opened .#{$ns}Select-arrow > svg {
    transform: rotate(180deg);
  }

  &:not(.is-disabled):hover {
    background: var(--Form-select-onHover-bg);
  }

  &--multi {
    .#{$ns}Select-value {
      position: static;
      user-select: none;
      line-height: calc(
        var(--Form-input-lineHeight) * var(--Form-input-fontSize) - #{px2rem(
            2px
          )}
      );
      display: inline-block;
      vertical-align: middle;
      font-size: var(--Form-selectValue-fontSize);
      color: var(--Form-selectValue-color);
      background: var(--Form-selectValue-bg);
      border: px2rem(1px) solid var(--Form-selectValue-borderColor);
      border-radius: px2rem(2px);
      margin-right: var(--gap-xs);
      margin-bottom: var(--gap-xs);
    }
    .#{$ns}Select-valueLabel {
      padding: 0 var(--gap-xs);
    }
  }

  &-placeholder {
    color: var(--Form-select-placeholderColor);
    line-height: var(--Form-input-lineHeight);
  }

  &-valueWrap {
    user-select: none;
    position: relative;
    flex-grow: 1;
  }

  &-clear {
    padding: px2rem(3px);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    z-index: 2;

    svg {
      fill: var(--Form-input-iconColor);
      width: px2rem(10px);
      height: px2rem(10px);
    }

    &:hover svg {
      fill: var(--Form-input-onHover-iconColor);
    }
  }

  &-optionArrowRight {
    display: inline-block;
    padding-right: px2rem(10px);

    svg {
      width: px2rem(12px);
      height: px2rem(12px);
      fill: var(--Form-input-iconColor);
    }
  }

  &-menuOuter {
    display: flex;
  }

  &-menu {
    width: px2rem(160px);
    max-height: px2rem(300px);
    background: var(--Form-select-menu-bg);
    color: var(--Form-select-menu-color);
    border: var(--Form-select-outer-borderWidth) solid
      var(--Form-input-onFocused-borderColor);
    box-shadow: var(--Form-select-outer-boxShadow);
    overflow-y: auto;
    overflow-x: hidden;

    &:not(:first-child) {
      border-left: 0;
    }

    .#{$ns}NestedSelect-option {
      position: relative;
      padding-left: px2rem(10px);
      min-height: var(--Form-input-height);
      line-height: var(--Form-input-height);
      cursor: pointer;
      display: flex;

      > .#{$ns}NestedSelect-optionLabel {
        flex: 1;
        cursor: pointer;
        span {
          display: inline-flex;
          word-break: break-all;
        }
      }

      &.is-active {
        color: var(--Form-select-menu-onActive-color);
        background: var(--Form-select-menu-onActive-bg);
      }

      &:hover {
        color: var(--Form-select-menu-onHover-color);
        background: var(--Form-select-menu-onHover-bg);
      }

      &:hover > .#{$ns}NestedSelect-childrenOuter {
        display: block;
      }

      .#{$ns}Checkbox {
        display: inline-block;
        padding-top: 0;
      }

      &.checkall {
        border-bottom: px2rem(1px) solid #eceff8;
      }
    }
  }
}

// 需要能撑开
@include media-breakpoint-up(sm) {
  .#{$ns}Form-control--sizeXs > .#{$ns}NestedSelect,
  .#{$ns}Form-control--sizeSm > .#{$ns}NestedSelect,
  .#{$ns}Form-control--sizeMd > .#{$ns}NestedSelect,
  .#{$ns}Form-control--sizeLg > .#{$ns}NestedSelect {
    display: inline-flex !important;
  }
}