OnBlur & onfocus

Xiaonei.com website has a good effect of on focus. When onfocus, change the css name and then show another style to current user.

onblur="dontnoteme(this)" onfocus="noteme(this);
function noteme(el){
el.parentNode.nextSibling.className="hey"
}
function dontnoteme(el){
el.parentNode.nextSibling.className="note"
}