Its really sound like a small job, i won't charge you anything for that except a real good review, I am Newly active freelancer on this platform, and i like to make my profile good with the help of good reviews.
There are 2 ways to do it:
[1] You provide only magento store URL, i will check and write CSS for it, and provide CSS code to you, you just need to add the code to your magento theme CSS file.
[2] you provide me login credentials for your magento store, and i will do it all for you.
I think, 1st option is more good,