function hSize() {
 var myWidth = 0, myHeight = 0;
  if( typeof( window.innerWidth ) == 'number' ) {
    //Non-IE
		myWidth = window.innerWidth;
		myHeight = window.innerHeight;

  } else if( document.documentElement && ( document.documentElement.clientWidth || document.documentElement.clientHeight ) ) {
    //IE 6+ in 'standards compliant mode'

		myWidth = document.documentElement.clientWidth;
		myHeight = document.documentElement.clientHeight;

  } else if( document.body && ( document.body.clientWidth || document.body.clientHeight ) ) {
    //IE 4 compatible
  		  myWidth = document.body.clientWidth;
  		  myHeight = document.body.clientHeight;
  }
  return myHeight;
}


if (hSize() > 600) {
document.write ('<link href="centrato.css" rel="stylesheet" type="text/css">');

}
else {
document.write ('<link href="accostato.css" rel="stylesheet" type="text/css">');

}