Spilt Layout on 7.1

Site URL: https://www.marlacinilia.com/home-option-2

I am trying apply a spilt screen layout the first section of my homepage with CSS.

I am using the following code but the change has now been applied to my footer as well. I do not want this. Can anyone advise how to ensure the change is only applied to the first section?

 <style>.page-section:nth-child(1){background-color:#4D5C42!important;} @media only screen and (min-width: 768px){ .page-section:nth-child(1) .section-background {width:50%!important; margin-left:50%!important}}<style>

.page-section:nth-child(1) >>> #page .page-section:nth-child(1)

.page-section:nth-child(1) .section-background >>> #page .page-section:nth-child(1) .section-background