var hauteur  = screen.height;
var largeur  = screen.width;

if (largeur <=1024)
document.write ("<link href='http://www.e-howto.com/style.css' rel='stylesheet' type='text/css'>");
else if (screen.width > 1024)     
document.write ("<link href='http://www.e-howto.com/style2.css' rel='stylesheet' type='text/css'>");