discourse/app/assets/stylesheets/common/float-kit/d-tooltip.scss

@keyframes d-tooltip-opening {
  0% {
    opacity: 0;
  }

  100% {
    opacity: 1;
  }
}

.fk-d-tooltip {
  &__trigger {
    display: inline-flex;
    cursor: pointer;

    .touch & {
      @include unselectable;
    }

    &-container {
      display: flex;
    }
  }

  &__inner-content {
    display: flex;
    overflow: hidden;
    overflow-wrap: break-word;
    padding: 0.5rem;
    align-items: center;
  }

  &__content {
    background-color: var(--secondary);
    border-radius: var(--d-border-radius);
    border: 1px solid var(--primary-low);
    box-shadow: var(--shadow-dropdown);
    z-index: z("max");
    width: max-content;
    position: absolute;
    top: 0;
    display: flex !important;
    padding: 0;

    &.-animated {
      animation: d-tooltip-opening 0.15s ease-in;

      &[data-placement^="bottom"] {
        transform-origin: top center;
      }

      &[data-placement^="top"] {
        transform-origin: bottom center;
      }

      &[data-placement^="right"] {
        transform-origin: center left;
      }

      &[data-placement^="left"] {
        transform-origin: center right;
      }
    }

    .arrow {
      z-index: z("max");
      position: absolute;
    }

    &[data-placement^="top"] {
      .arrow {
        bottom: -10px;
        rotate: 180deg;
      }
    }

    &[data-placement^="top-start"] {
      .arrow {
        margin-left: 10px;
      }
    }

    &[data-placement^="bottom"] {
      .arrow {
        top: -10px;
      }
    }

    &[data-placement^="right"] {
      .arrow {
        rotate: -90deg;
        left: -10px;
      }
    }

    &[data-placement^="left"] {
      .arrow {
        rotate: 90deg;
        right: -10px;
      }
    }
  }
}