Example of creating a glitchy effect with the :hover selector:

Source Code: (back to article)

<!DOCTYPE html>
<html>
  <head>
    <title>Title of the document</title>
    <style>
      .content {
        display: flex;
        width: 100vw;
        height: 100vh;
        background-color: black;
        background-image: url("https://images.unsplash.com/photo-1489875347897-49f64b51c1f8?ixlib=rb-1.2.1&ixid=eyJhcHBfaWQiOjM4MDE5fQ&auto=format&fit=crop&w=1050&q=80");
        background-repeat: no-repeat;
        background-position: center;
        background-size: cover;
      }
      .text {
        margin: auto;
        font-family: 'Montserrat', sans-serif;
        font-size: 120px;
        text-transform: uppercase;
      }
      .glitch {
        position: relative;
        color: white;
        mix-blend-mode: lighten;
      }
      .glitch:before,
      .glitch:after {
        content: attr(data-text);
        position: absolute;
        top: 0;
        width: 100%;
        background: black;
        clip: rect(0, 0, 0, 0);
      }
      .glitch:before {
        left: -1px;
        text-shadow: 1px 0 rgba(255, 0, 0, 0.7);
      }
      .glitch:after {
        left: 1px;
        text-shadow: -1px 0 rgba(0, 0, 255, 0.7);
      }
      .glitch:hover:before {
        text-shadow: 4px 0 rgba(255, 0, 0, 0.7);
        animation: glitch-loop-1 0.8s infinite ease-in-out alternate-reverse;
      }
      .glitch:hover:after {
        text-shadow: -5px 0 rgba(0, 0, 255, 0.7);
        animation: glitch-loop-2 0.8s infinite ease-in-out alternate-reverse;
      }
      @keyframes glitch-loop-1 {
        0% {
          clip: rect(36px, 9999px, 9px, 0);
        }
        25% {
          clip: rect(25px, 9999px, 99px, 0);
        }
        50% {
          clip: rect(50px, 9999px, 102px, 0);
        }
        75% {
          clip: rect(30px, 9999px, 92px, 0);
        }
        100% {
          clip: rect(91px, 9999px, 98px, 0);
        }
      }
      @keyframes glitch-loop-2 {
        0% {
          top: -1px;
          left: 1px;
          clip: rect(65px, 9999px, 119px, 0);
        }
        25% {
          top: -6px;
          left: 4px;
          clip: rect(79px, 9999px, 19px, 0);
        }
        50% {
          top: -3px;
          left: 2px;
          clip: rect(68px, 9999px, 11px, 0);
        }
        75% {
          top: 0px;
          left: -4px;
          clip: rect(95px, 9999px, 53px, 0);
        }
        100% {
          top: -1px;
          left: -1px;
          clip: rect(31px, 9999px, 149px, 0);
        }
      }
    </style>
  </head>
  <body>
    <div class="content">
      <h1 class="text glitch is-glitching" data-text="Hover me!">Hover me!</h1>
    </div>
  </body>
</html>