box-shadow

基本解释

Well, here is a post on the basics of the new properties: text-shadow, box-shadow, and border-radius.
这篇文章将对 CSS 的几个新属性 (text-shadow，box-shadow，and border-radius) 做基本介绍。
The css3 property box-shadow allows you to add a shadow effect without using images to a selected element.
允许我们添加阴影效果，而不必在特定的元素上实用图像.
h-impression.blog.163.com
The structure for box shadow is same as the text-shadow property: x-offset, y-offset, blur, and color.
盒阴影的结构和 text-shadow 相同，x 轴偏移，y 轴偏移，模糊，颜色。