I want to let user to choose the colour of the border, the background and the background image. How can I do that? What I want is like the user choose blue from a dropdown list then this code below will change to the relative colour and image.

.ui-widget-header { border: 1px solid #f86da8; background: #f84a94 url(images/ui-bg_gloss-wave_55_f84a94_500x100.png) 50% 50% repeat-x; 

Thanks for helping.

I would say that one approach could be that you use jQuery and use the addClass and removeClass methods so that when a certain event is triggered such as a button click, you can assign the new styles.

Do you at least have the HTML code for the page to start with?