docs: function Stylesheet() {
    var styleElement = document.createElement('style'),
      head = document.getElementsByTagName('head')[0];
  
    head.appendChild(styleElement);
  
    // Safari does not see the new stylesheet unless you append something.
    // However!  IE will blow chunks, so ... filter it thusly:
    if (!window.createPopup) {
      styleElement.appendChild(document.createTextNode(''));
    }
  
    this.sheet = document.styleSheets[document.styleSheets.length - 1];
  }