进度：
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初版翻译完成 2016.3.29-2016.5.23
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全部章节refine完成 2017.7.26-2018.3.31
官方文档：http://www.w3.org/TR/2011/REC-CSS2-20110607/
W3C索引：https://www.w3.org/2005/11/Translations/Query?titleMatch=css+2.1&lang=zh-hans&search1=Submit
中文翻译：http://www.ayqy.net/doc/css2-1/cover.html
License：MIT，可以随意带走，但不建议二次发布，因为后续错误更正难以同步（存在N个错误翻译版并不比没有翻译版好多少）
本文档是《层叠样式表2级修订版1（CSS 2.1）规范（W3C推荐2011-06-07）》的简体中文翻译。
由于译者水平有限，可能存在错误，中文翻译仅供参考，准确的规范内容请查看官方文档。 （如在阅读过程中发现任何错误，请提出Issue/PR或者联系ayqy，以便及时更正。）
在本文档的翻译过程中（2016.3.29-2016.5.23），CSS 2.2规范有了新的进展（2016.4.12发布了第一份工作草案）。 目前（2016）得到最广泛支持的版本仍然是CSS 2.1（即本规范），关于CSS规范的最新情况查看CSS。
见以下邮件原文（译者 to w3c-translators），内容拒绝翻译：
I have confirmed that another translation (the second link above) is ongoing (and I consulted it during this translation), but it seems something went wrong with it.(Many months passed away, but it turns to nowhere). So...just like the way Momdo Nakamura did it.
对比W3C日文文档的完成度，一些事情是有原因的。
2个月时间，只想把前端课本之一仔细看一遍（在出厂之前让自己再过一道质检）。
还有，w3c工作人员很亲切的，并不可怕，而有些事情需要我们FEers去完成，不是么？
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