Javascript Media Queries (with listener)

mq.js

/* JavaScript Media Queries */
if (matchMedia) {
	var mq = window.matchMedia("(min-width: 1200px)");
	mq.addListener(WidthChange);
	WidthChange(mq);
}

// media query change
function WidthChange(mq) {

	var msg = (mq.matches ? "more" : "less") + " than 1200px pixels";

	if (mq.matches) {
		document.getElementById("owner").style.border = "1px solid black";
	} else {
		document.getElementById("owner").style.border = "3px solid green";
	}

}