data8/_sass/page/objects/_objects.tooltip.scss

/**
 * A minimal CSS-only tooltip copied from:
 *   https://codepen.io/mildrenben/pen/rVBrpK
 *
 * To use, write HTML like the following:
 *
 * <p class="o-tooltip--left" data-tooltip="Hey">Short</p>
 */

$cubic: cubic-bezier(0.64, 0.09, 0.08, 1);

.o-tooltip {
  position: relative;
  &:after {
    opacity: 0;
    visibility: hidden;
    position: absolute;
    content: attr(data-tooltip);
    padding: 6px;
    top: 1.4em;
    left: 50%;
    transform: translateX(-50%) translateY(-2px);
    background: grey;
    font-size: 0.7rem;
    color: white;
    white-space: nowrap;
    z-index: 2;
    border-radius: 2px;
    transition: opacity 0.2s $cubic, transform 0.2s $cubic;
  }
  &:hover {
    &:after {
      display: block;
      opacity: 1;
      visibility: visible;
      transform: translateX(-50%) translateY(0);
    }
  }
}

.o-tooltip--left {
  @extend .o-tooltip;

  &:after {
    top: 0;
    left: 0;
    transform: translateX(-102%) translateY(0);
  }
  &:hover {
    &:after {
      transform: translateX(-100%) translateY(0);
    }
  }
}