你有三种选择：使用平面图像模拟的透明度，使用不能跨浏览器兼容的PNG格式，或者去折腾CSS基本的透明选择器和滤镜。

You had three choices: simulate transparency using flat images, deal with PNG's cross-browser incompatibilities, or struggle with CSS 'basic transparency selectors and filters.

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图10中纹理图像的灰色位透明度为60%。

The gray bits in the texture image in Figure 10 are 60 percent transparent.

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PHG对于网络图像来说是个极好的文件格式，因为它有一种GIF没有的典雅，支持浏览器透明度。

PNG is an excellent filetype for Internet graphics, as it supports transparency in browsers with an elegance that GIF does not possess.

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