function roundedCorners() {
  var divs = document.getElementsByTagName('div');
  var rounded_divs = [];
  for (var i = 0; i < divs.length; i++) {
    if (/\brounded\b/.exec(divs[i].className)) {
      rounded_divs[rounded_divs.length] = divs[i];
    }
  }
  for (var i = 0; i < rounded_divs.length; i++) {
    var original = rounded_divs[i];
    original.className = original.className.replace('rounded', 'rounded4');
    var tr = document.createElement('div');
    tr.className = 'rounded1';
    original.parentNode.replaceChild(tr, original);
    var tl = document.createElement('div');
    tl.className = 'rounded2';
    var br = document.createElement('div');
    br.className = 'rounded3';tr.appendChild(tl); tl.appendChild(br);br.appendChild(original);}}
window.onload = roundedCorners;