<!DOCTYPE html>
<html>
  <body>
    <style>
      .scroller {
        width: 200px;
        height: 200px;
        border: solid 1px black;
        overflow: scroll;
        scroll-snap-type: both mandatory;
        position: relative;
        resize: both;
      }
      .target {
        scroll-snap-align: start;
        width: 50px;
        height: 50px;
        background-color: green;
        position: absolute;
      }
      .target:target {
        background-color: blue;
      }
      .target:focus {