function walkTheDOM (node, func) {
func(node);
node = node.firstChild;
while (node) {
walkTheDOM(node, func);
node = node.nextSibling;
}
}

function getElementsByClassName (className) {
var results = [];
walkTheDOM(document.body, function (node) {
var a, c = node.className, i;
if (c) {
a = c.split(' ');
for (i=0; i<a.length; i++) {
if (a[i] === className) {
results.push(node.id);
break;
}
}
}
});
return results;
}

function hideAllByClass (className){
	var results = [];
	results = getElementsByClassName (className);
	for (i=0; i<results.length; i++) { 
		document.getElementById(results[i]).style.display='none';
	}
}
function showAllByClass (className){
	var results = [];
	results = getElementsByClassName (className);
	for (i=0; i<results.length; i++) { 
		document.getElementById(results[i]).style.display='block';
	}
}
function resetAllByClass (className){
	var results = [];
	results = getElementsByClassName (className);
	for (i=0; i<results.length; i++) { 
		document.getElementById(results[i]).style.fontSize='13px';
		document.getElementById(results[i]).style.lineHeight='17px';
	}
}
function spaceAllByClass (className){
	var results = [];
	results = getElementsByClassName (className);
	for (i=0; i<results.length; i++) { 
		document.getElementById(results[i]).style.marginTop='0px';
		document.getElementById(results[i]).style.marginBottom='0px';
	}
}