background-color: rgba(0,0,0,.5);该属性值最后一个参数，无法设置文字透明！

[dingguangbo]

https://github.com/mdn/css-examples/blob/master/learn/solutions.md#backgrounds-and-borders该文档中要求，使用rgba颜色为半透明的标题添加了背景颜色， background-color: rgba(0,0,0,.5);这个属性值中最后一个参数无法让文字透明（无法让标题透明）。如果让文字在背景中透明，正确的方法应该使用opacity: 0.5;这个属性！

最初学习文档是https://developer.mozilla.org/zh-CN/docs/Learn/CSS/Building_blocks/Backgrounds_and_borders玩转背景和边框中，第3个要求：给h2标题一个半透明的黑色背景颜色，并使文本为白色。但是解决方案中用了background-color: rgba(0,0,0,.5);所以这个不对的。

[yarusome]

Either the current en-US version of the test says:

3. Give the <h2> a semi-transparent black background color, and make the text white.

or the current zh-CN version says:

3. 给<h2>一个半透明的黑色背景颜色，并使文本为白色。

Both clearly suggest that it's the background instead of the text that needs to be semi-transparent, so this issue is out of misunderstanding.

@estelle or @teoli2003, could you close this issue? Thanks in advance!

[yin1999]

Both clearly suggest that it's the background instead of the text that needs to be semi-transparent, so this issue is out of misunderstanding.

👍, I think we could close this :)

[estelle]

Yes. This is correct. The background, not the text, should be semi-opaque.