var allHTML = new Array();
function getElementByClass(theClass) {
    var allHTML = document.getElementsByTagName("a");
    for (i = 0; i < allHTML.length; i++) {
        if (allHTML[i].className == theClass + "_on") {
            allHTML[i].className = theClass;
        }
    }

    allHTML = document.getElementsByTagName("span");
    for (i = 0; i < allHTML.length; i++) {
        if (allHTML[i].className == "content") {
            allHTML[i].style.display = 'none';
        }
    }
}
function ShowContent(id, contentPanel, css) {
    getElementByClass(css);
    var link = document.getElementById(id);
    link.className = css + "_on";

    var c = document.getElementById(contentPanel);
    c.style.display = 'block';
}