function get_page_size() {
    var de = document.documentElement;
    var width = window.innerWidth || self.innerWidth || (de && de.clientWidth) || document.body.clientWidth;
    var height = window.innerHeight || self.innerHeight || (de && de.clientHeight) || document.body.clientHeight;
    return [width, height];
}

function auto_height(side_left, side_right) {
    var height_left = $(side_left).height();
    var height_right = $(side_right).height();
    if (height_left < height_right) {
        $(side_left).css('height', height_right + 'px');
    }
    else {
        $(side_right).css('height', height_left + 'px');
    }
}