Change background container of page and post from white to color

http://sphysics.com/WP1 is the site. I’ve figured almost everything out with CSS EXCEPT how to change the container on pages and posts from white to another color or image?

Specifically, look at http://sphysics.com/WP1/products/. It has the white border I cannot change for the life of me. Neither can I on any of the pages or posts.

Any help appreciated!!
Thanks,
Deborah

Dear Deborah,

Could you please try to apply the following CSS code through the Simple Custom CSS plugin or child theme’s style.css?

.hentry .post-content, 
.single .hentry, 
.page .hentry {   
   border: none;
   background-color: #ff0000;
}  

Regards,
Kharis