window.onload = function() {
    am_onload();

    var heightMax = 0;
    var categories = [];
    for (var i = 0; i < categoriesIds.length; i++)
    {
        var category = document.getElementById('category_' + categoriesIds[i]);
        if (category.offsetHeight > heightMax)
        {
            heightMax = category.offsetHeight;
        }
        categories.push(category);
    }

    for (var i = 0; i < categories.length; i++)
    {
        categories[i].style.height = heightMax + 'px';
    }
}