 height: 100px;
        width: 100px;
      }
      @supports selector(input::details-content::before) {
        div { background-color:green; }
      }
    </style>
  </head>
  <body>
    <p>Test passes if there is a <strong>filled green square</strong> and <strong>no red</strong>.</p>
    <div></div>
  </body>
</html>
