How to set the max header width to 2160px and the main body section to 1400px (or something else)

[dtffox]

Sit- https://foxtree-designs.myshopify.com/

Theme - Combine

I would like to set the header width to respond to whatever display a viewer is using ultimately to keep the logo on the far left and have the body section of my site to be centered and not extended to the edges like the logo on monitors that are 2160. My apologies for the lack of terminology.  

Additionally, on my homepage I have a 4 column section that I would like to be 2 columns on mobile rather than 1 column.

Thank you in advance!

[zaczee]

Hi,

Add this CSS code
Online Store > Themes > Edit code > Assets > custom.css or theme.css

.header__top, .header__bottom { max-width: 90%; }