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29 lines
974 B
Plaintext
29 lines
974 B
Plaintext
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CSS Length Reference
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To bound, or not to bound, that is the question
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It's quite a reasonable request, really, and it's already been implemented
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for HTML. That is, length bounding. It makes little sense to let users
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define text blocks that have a font-size of 63,360 inches (that's a mile,
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by the way) or a width of forty-fold the parent container.
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But it's a little more complicated then that. There are multiple units
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one can use, and we have to a little unit conversion to get things working.
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Here's what we have:
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Absolute:
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1 in ~= 2.54 cm
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1 cm = 10 mm
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1 pt = 1/72 in
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1 pc = 12 pt
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Relative:
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1 em ~= 10.0667 px
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1 ex ~= 0.5 em, though Mozilla Firefox says 1 ex = 6px
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1 px ~= 1 pt
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Watch out: font-sizes can also be nested to get successively larger
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(although I do not relish having to keep track of context font-sizes,
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this may be necessary, especially for some of the more advanced features
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for preventing things like white on white).
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