// load external link <a href="link" rel="external">link</a>
function externalLinks() {
	if (!document.getElementsByTagName) return;
	var anchors = document.getElementsByTagName("a");
	for (var i=0; i<anchors.length; i++) {
		var anchor = anchors[i];
		if (anchor.getAttribute("href") && anchor.getAttribute("rel") == "external") anchor.target = "_blank";
	}
}
window.onload = externalLinks;

function show_hide(div_id) {
	var obj = document.getElementById(div_id);

	if(obj.style.display == 'block') {
		obj.style.display = 'none';
	} else {
		obj.style.display = 'block';
	}
}