W3Schools Tryit Editor

<!DOCTYPE html>
<html>
<head>
  <title>Select images</title>
  <style>
    #app {
      display: flex;
      flex-wrap: wrap;
      justify-content: space-around;
      width: 80%;
      border: dashed black 1px;
    }
    #app > div {
      display: block;
      flex-basis: 80px;
      aspect-ratio: 1;
      margin: 5px;
    }
    div > img {
      box-sizing: border-box;
      width: 100%;
      padding: 3px;
      border: solid white 4px;
      border-radius: 5px;
    }
    img:hover {
      cursor: pointer;
    }
    .selClass {
      border: solid brown 4px;
      background-color: lightpink;
    }
  </style>
</head>
<body>

<h1>Example: Selecting images with v-bind:class</h1>
<p>This is an example of assigning a class with Vue (v-bind:class).</p>
<p>Click on an image to assign or remove the class "selClass".</p>
<div id="app">
  <div v-for="(img, index) in images">
    <img v-bind:src="img.url" v-on:click="select(index)" v-bind:class="{selClass: img.sel}">
  </div>
</div>

</body>
</html>