background的缩写顺序

background : background-color || background-image || background-repeat || background-attachment || background-position

示例：

div { background: red no-repeat scroll 5% 60%; }
body { background: url("images/aardvark.gif") repeat-y; }
pre { background: url("images/aardvark.gif") top; }
caption { background: fuchsia; }