Change pre footer widget area to opaque

Hello,

First post on here so take it easy!
I have 2 questions,

firstly:
I am wanting some help to change my pre footer colour to opaque, it is currently grey as you can see here https://www.norfolkpremiergolf.co.uk/new/ (where the weather widget is)….so i would like to change this to clear etc.

secondly, how do i change the width of a widget/widget area through css code if i cant do it under appearance-widget?

hope this makes sense.

would love some help as this is sending me round the bend!

Jack

ps. wordpress and css novice!