How to make it transparent

Hi everyone.

Hope you guys can help me..

I just installed the Restaurant Directory theme but the “Search style 3” on the frontpage have a yellow background. How can i move the background so it it transparent?

I attached a photo from this website, thats the theme i have and i want it to look like that.

My english is not the best and im new to try this stuff so i hope its okey.

Thanks from now.

Kind regarts
Dennis