modules/layout_builder/css/off-canvas.pcss.css
/**
 * @file
 * Layout Builder styling for off-canvas UI.
 */

#drupal-off-canvas-wrapper {
  & .layout-selection {
    margin: 0;
    padding: 0;
    list-style: none;

    & li {
      position: relative; /* Anchor throbber. */
      padding: calc(0.25 * var(--off-canvas-vertical-spacing-unit));
      border-bottom: 1px solid var(--off-canvas-border-color);

      &:last-child {
        padding-bottom: 0;
        border-bottom: none;
      }
    }

    /* Horizontally align icon and text. */
    & a {
      display: flex;
      flex-wrap: wrap;
      align-items: center;
      gap: 10px;
      padding: 10px;
    }
  }

  /*
   * This is the styling of the SVG within the layout selection list.
   */
  & .layout-icon__region {
    fill: var(--off-canvas-text-color);
    stroke: transparent;

    @media (forced-colors: active) {
      fill: canvastext;
    }
  }

  & .inline-block-create-button {
    --icon-size: 16px;

    position: relative; /* Anchor pseudo-element. */
    display: block;
    padding: 24px;
    padding-inline-start: calc(2 * var(--off-canvas-padding) + var(--icon-size) / 2); /* Room for icon */
    border-bottom: 1px solid #333;
    font-size: 16px;

    /* Plus icon. */
    &::before {
      position: absolute;
      top: 50%;
      left: var(--off-canvas-padding);
      width: var(--icon-size);
      height: var(--icon-size);
      content: "";
      transform: translateY(-50%);
      background-image: url(../../../misc/icons/bebebe/plus.svg);
      background-repeat: no-repeat;
      background-size: contain;

      @media (forced-colors: active) {
        background: linktext;
        mask-image: url(../../../misc/icons/bebebe/plus.svg);
        mask-repeat: no-repeat;
        mask-size: contain;
      }
    }
  }

  & .inline-block-create-button,
  & .inline-block-list__item {
    margin: 0 calc(-1 * var(--off-canvas-padding));
    color: var(--off-canvas-text-color);

    &:hover {
      background-color: rgb(255, 255, 255, 0.05);
    }

    &:focus {
      outline-offset: -4px; /* Prevent outline from being cut off. */
    }
  }

  & .inline-block-list {
    margin: 0 0 calc(2 * var(--off-canvas-vertical-spacing-unit));
    padding: 0;
    list-style: none;

    & li {
      position: relative; /* Anchor throbber. */
      margin: 0;
      padding: calc(0.25 * var(--off-canvas-vertical-spacing-unit)) 0;

      &:last-child {
        padding-bottom: 0;
        border-bottom: none;
      }
    }
  }

  /* This is the <a> tag. */
  & .inline-block-list__item {
    display: block;
    flex-grow: 1;
    padding: calc(2 * var(--off-canvas-vertical-spacing-unit)) var(--off-canvas-padding);
    border-bottom: 1px solid var(--off-canvas-border-color);
  }

  /* Highlight the active block in the Move Block dialog. */
  & .layout-builder-components-table__block-label--current {
    padding-left: 17px;
    border-left: solid 5px;
  }
}
