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  <div class="wrapper">
    <p>Hello, playing around with tooltips! <a href="">Hover this link</a>. Each link will show you what their href is on hover. <a href="">Check out this one!</a></p>

      Browser support isn't really happening yet but in theory you could eventually have attributes like <code>data-tooltip-background</code> to have different bg colors for different tooltips, or have a <code>data-tooltip-text</code> on links and fall back to href if it doesn't exist. You can read about that <a href="">here</a>. It would look something like -
a:hover::after {
  content: attr(data-tooltip-text string, attr(href));
    <p>Thanks for visiting! This pen was created for the <a href="">tooltip css challenge</a>.</p>



                @keyframes tooltip {
  0% {
    transform: scale(0) translateY(-110%);
    opacity: 0;
  100% {
    transform: scale(1) translateY(-110%);
    opacity: 1;

body {
  padding: 50px;
  font-family: sans-serif;
  font-size: 18px;
  background: white;
  line-height: 1.5;

.wrapper {
  width: 80%;
  max-width: 500px;
  margin: 0 auto;

a {
  position: relative;
  color: blue;

a:hover::after {
  animation: tooltip 100ms ease-in forwards;
  transform: translateY(-110%);
  position: absolute;
  content: attr(href);
  background: rgba(0,0,0,.9);
  top: 0;
  left: 0;
  right: 0;
  width: fit-content; 
  margin: auto;
  color: white;
  padding: 2px 4px;
  border-radius: 2px;
  font-size: .7em;

code {
  color: hotpink;
  font-family: courier, monospace;