function setWeekColor() {
    var calendar = document.getElementById('wp-calendar');
    if (!calendar) return;
    var th = calendar.getElementsByTagName('th');
    for (i = 0; i < th.length; i++) {
        if (th[i].getAttribute('title') == '日曜日') {
            th[i].className = 'holiday';
        }
        if (th[i].getAttribute('title') == '土曜日') {
            th[i].className = 'saturday';
        }
    }
}

function setWeekColor_b() {
    var calendar_b = document.getElementById('ec3_big_cal');
    if (!calendar_b) return;
    var th_b = calendar_b.getElementsByTagName('th');
    for (j = 0; j < th_b.length; j++) {
        if (th_b[i].getAttribute('title') == '日曜日') {
            th_b[i].className = 'holiday';
        }
        if (th_b[i].getAttribute('title') == '土曜日') {
            th_b[i].className = 'saturday';
        }
    }
}