动态调用CSS文件，一般用于页面的多种颜色选择，通过调用不同的css实现不用的页面颜色效果。
< type="text/" language="script">
var _sn = ["df/common", "df/home2010"];
var _su = "";
var Swidth = screen.width; var _se, _st;
for (i in _sn) {
_se = document.createElement("link");
_se.type = "text/css";
_se.rel = "stylesheet";
if (Swidth >= 1280) {
_st = _su + _sn[i] + ".w.css";
} else {
_st = _su + _sn[i] + ".css";
}
_se.href = _st;
document.getElementsByTagName("head")[0].appendChild(_se);
}
</script>
