I am a newbie. I am using the sunflower template. I want to change the left categories sidebox design similar to the horizontal drop down menu but I want it the expanding type instead of slide or flyout.
I am not an expert in php, css. I try to edit the css and play around with it but not success. There are 2 files. Stylesheet.css and stylesheet_cssboxes.css. Which file should I edit. Can someone pls help.

My site bruneipartyshop.com