There is another technique I have found using a negative parameter for shadow density to fake an area shadow.

我发现的另一个技巧是可以用阴影的负参数来模拟面阴影。

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Finally add a subtle Outer Glow using black at 15% opacity to give a slight shadow to the content area.

最后添加一个外发光，黑色的15%透明度的，于是一个淡淡的内容区的阴影就这样出现了。

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They help the menu or window stand out from the background by reinforcing its dimensions. They also block out the noise of the content beneath the window by darkening the area around it with a shadow.

这些阴影通过增加菜单或者窗口的维度来使它们变得醒目，同时也能来把这块区域变暗以阻止下方内容的干扰。

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He insisted that no shadow ministers should shadow the area they covered in government.

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The crush at Sheffield's Hillsborough Stadium on April 15, 1989, has cast a lasting shadow over Liverpool and the surrounding Merseyside area.

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Shadow work and pensions secretary Liam Byrne said this was a particularly worrying area.

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