opacity

英[əʊˈpæsəti] 美[oʊˈpæsəti]

n.Opacity; puzzling; difficult to understand; vague

Plural: opacities

css3 opacity property syntax

Function:Retrieve or set the opacity of the object.

Note:For IE browsers that do not yet support the opacity attribute, you can use IE's private filter attribute to achieve the same effect as opacity

css3 opacity property example

      
  
下例是一个半透明的效果：
 
不透明度为100%的box
 
不透明度为50%的box