Mozilla建议的CSS书写顺序

* mozilla.org Base Styles
* maintained by fantasai
* (classes defined in the Markup Guide -http://mozilla.org/contribute/writing/markup)
*/
/* Suggested order:
//显示属性
* display
* list-style
* position
* float
* clear
//自身属性
* width
* height
* margin
* padding
* border
* background
//文本属性
* color
* font
* text-decoration
* text-align
* vertical-align
* white-space
* other text
* content