is is my website</h1>

    <script>
      const select = document.querySelector('select');
      const html = document.querySelector('html');

      select.onchange = function() {
        const choice = select.value;

        switch(choice) {
          case 'black':
            update('black','white');
            break;
          case 'white':
            update('white','black');
            break;
          case 'purple':
            update('purple','white');
            break;
          case 'yellow':
  