function menuDecoration() {

    var menu, links;

    menu = document.getElementById('menu');
    if (!menu) return;

    links = menu.getElementsByTagName('a');

    for (var i = 0; i < links.length; i++) {

        var decoration = document.createElement('span');
        decoration.className = 'decoration';

        links[i].appendChild(decoration);

    }

}


window.onload = function() {
    menuDecoration();
};