Ionic, change background color with param from RestApi

I guys im creating an app in ionic most part of the App come from my rest Api.
Having a hexadecimal color for AppHeader and background.

This Code from other post in ionic forum do the job.

In CSS. example:

.background, .background .pane, .background .item, .background .item-complex .item-content{background-color: #f7f8fa;}

In html:

<ion-nav-view class="background"></ion-nav-view>

Well I include jQuery to my app…

Then in My controller then code this.

jQuery(".background").css("background-color","yellow ");
   jQuery(".background .pane").css("background-color","yellow ");
   jQuery(".background .item").css("background-color","yellow ");
   jQuery(".background .item-complex .item-content").css("background-color","yellow ");

this is not working properly dont do the same of the css…
the idea i have is put the variable with my backgroun color instead yellow.


If un know how i can do this please let me know. How I change the
completely the background of the App in ionic using a Variable provide
from Api and change constantly.