New to moodle - need some help

Hey,

Im not sure I'm posting in the right section but - As stated I'm new to moodle and PHP, but not to CSS/HTML. So preferably I'd like to avoid as much PHP as possible.

So basically I need to create a new theme or custom CSS for an existing theme to help our moodle courses look similar to our company website. (I've attached screenshots)

Can anyone kick me in the right direction and provide some guidance? I have three custom themes sitting on my computer that I'm about to look at but all three seem to be a nice layout. Currently our courses are using the "Brick" theme.