verzia = navigator.appVersion.substring(0, 1);
  if (navigator.appName == 'Microsoft Internet Explorer'  &&  (verzia >= 4))
{
  document.styleSheets[0].addRule("h1", "position: relative; margin-bottom: 20px; font-size: x-large;", 0);
  document.styleSheets[0].addRule("h4", "font-weight: 500;", 0);
  document.styleSheets[0].addRule("body", "margin-left: 20px; margin-right: 20px;", 0);
}