CSS3 attr() function

CSS Values and Units Level 3 adds the ability to use attr() on any CSS property, not just content, and to use it for non-string values (e.g. numbers, colors).

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56 9.3 4.4
14 52 57 10 10.0-10.2 4.4.3-4.4.4 4
11 15 53 58 10.1 44 10.3 all 56 10 37 57 52 11 11.4 5 1.2 7.12
54 59 TP 45
55 60 46
56 61

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