// Navigator 6 and up
  if (is_nav6up) {
    document.write('<'+'link rel="stylesheet" type="text/css" href="styles/sty_nav6.css">');
  }
  // Navigator 4
  else if (is_nav4) {
   document.write('<'+'link rel="stylesheet" type="text/css" href="styles/sty_nav4.css" />');
  }
  // IE 5
  else if (is_ie5) {
    document.write('<'+'link rel="stylesheet" type="text/css" href="styles/sty_ie5.css">');
  }
 // IE 5.5
  else if (is_ie5_5) {
    document.write('<'+'link rel="stylesheet" type="text/css" href="styles/sty_ie5.css">');
  }
  // IE 6 and up
  else if (is_ie6up) {
    document.write('<'+'link rel="stylesheet" type="text/css" href="styles/sty_ie6u.css">');
  }
  // IE 4
//  else if (is_ie4) {
//    document.write('<'+'link rel="stylesheet" type="text/css" href="styles/style-ie4.css" />');
//  }
//Opera 5 and up
 if (is_opera5up) {
    document.write('<'+'link rel="stylesheet" type="text/css" href="styles/sty_op5u.css">');
  }