t.setAttribute('data-theme', el.value) }
  
    function switchCSS(cssid, el){ document.getElementById(cssid).href = el.value; }
  
    function addFontSize(addPx){
      html = document.querySelector('html');
      currentSize = parseFloat(window.getComputedStyle(html, null)
        .getPropertyValue('font-size'));
      html.style.fontSize = (currentSize + addPx) + 'px';
    }
  
    function toggleDarkMode(el){
      var theme='light'
      if (el.innerText == '☪'){
        el.innerText =