Drupal7 CSS Injector

CSS injector module allows you to add CSS code to your site. And it automatically created style sheets and saved it. You can apply CSS code for one or many pages. That saves a lot of time. You should install it if you know CSS.
https://drupal.org/project/css_injector
http://drupaltutor.com/blog/2013-06/using-css-injector-module-change-design-your-drupal-website

 Click "Create a new rule."　

Add CSS code and set up