In the includes/templates/your-custom-template/css/stylesheet.css, normally there is a code as below: body {margin: 0;font-family: verdana, arial, helvetica, sans-serif;font-size: 62.5%;color: #888787;background: #fff;}. I have a question what's the difference between "color" and "backgroud". Which one actually dicides the backgroud of the body?