var OPENED_SELECTOR = '\u25bc';
var CLOSED_SELECTOR = '\u25b6';

function toggle(selector) {
    var data = document.getElementById(selector.id+"-data");
    var opened = data.style.display == "block";

    selector.innerHTML = opened ? CLOSED_SELECTOR : OPENED_SELECTOR;
    data.style.display = opened ? "none" : "block";
}

function mouseOver(selector) {
    selector.className = "selector selected";
}

function mouseOut(selector) {
    selector.className = "selector deselected";
}