Tips to make changeable layout for a website

I have to make a control panel for a website that lets the user to change the layout of the website , like changing the position of a certain div or change its size . This is my first time to make a something like that , all I have in my minds is storing css values in the database and let the user change it . I know that wordpress and other CMS have this feature but there is no way that I can use that in my project . thanks in advanced.