팝업창 가운데 띄우기

$(function() {
    var sw = screen.width;
    var sh = screen.height;
    var cw = document.body.clientWidth;
    var ch = document.body.clientHeight;
    var top  = sh / 2 - ch / 2 - 100;
    var left = sw / 2 - cw / 2;
    moveTo(left, top);
});