var t_id = setInterval(animate, 20);
var pos = 0;
var dir = 2;
var len = 0;

function animate() {
    var elem = document.getElementById('progress');
    if (elem != null) {
        if (pos == 0) len += dir;
        if (len > 32 || pos > 79) pos += dir;
        if (pos > 79) len -= dir;
        if (pos > 79 && len == 0) pos = 0;
        elem.style.left = pos;
        elem.style.width = len;
    }
}

function remove_loading() {
    this.clearInterval(t_id);
    var targelem = document.getElementById('loader_container');
    targelem.style.display = 'none';
    targelem.style.visibility = 'hidden';
    var t_id = setInterval(animate, 60);
}