Alvaro Montoro has a great thread (and blog post) of a bunch of CSS value functions in “the first public draft of the CSS Values and Units Level 5 Module”. It can’t be overstated how powerful some of this stuff is going to be. The attr() stuff enables much more a powerful realtime HTML<>CSS connection. The sibling-*() functions will be fantastic for staggering effects and quanity-driven layouts. And giving us runtime random() will unleash lots of interesting design creativity.
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