[1] CSS Conditional Rules Module Level 3 ( (12/12/2012, 2:06:24 PM 版)) <http://www.w3.org/TR/2012/WD-css3-conditional-20121213/>
[2] DOMTokenList's supports() takes a single token · whatwg/dom@a97debc (1/2/2016, 2:19:23 AM 版) <https://github.com/whatwg/dom/commit/a97debcb4da2c1fc0753ff6fb78638243b5731a3>
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