function showPane(id) {
    for (var i = 1; i < 5; i++) {
        if (id == i) {
            document.getElementById("content" + i).style.display = 'block';
            document.getElementById("title" + i).style.backgroundImage = "url(image/gonggua.jpg)";
        } else {
            document.getElementById("content" + i).style.display = 'none';
            document.getElementById("title" + i).style.backgroundImage = "url(image/huisedit%20.jpg)";
        }
    }
}