Physical units like points and inches render inconsistently because operating systems make different assumptions about the pixels per inch of a screen.
Physical units intentionally render at a fixed physical size across devices (with the exception of some broken browsers). If I ask my browser for an 8.5in-wide box, and hold a piece of (US letter) paper up to my screen, the width matches exactly.
If you really want a fixed size in pixels, use pixels, but please don't for anything other than images (and take care with images).
Sure, but this is only true if the operating system knows the correct ppi for the display (not guaranteed) and only useful if you know the physical dimensions of the client (almost never).
Just like most of web design, all of this seems so insane. We can't use pixels, so let's use ems. But ems don't work, so we need rems. Those don't always work, so let's also specify pixels. WTF!
It shouldn't matter what the sizes are, only the size relative to other element matters when it comes to the design.
The unit might as well be 1d (for distance) because the browser can scale the representation of the scenegraph up and down like any vector graphics viewers, think PDF. It's also a small task to offer an alternative CSS for those who want to read the text instead of admiring the spaciousness of the design and the tininess of the fonts.
Pixels work fine in real browsers, they worked fine even since and they don't require strange math or resetting a child element. And because they work, they don't require a fallback.
If a specific browser doesn't support a very specific feature, I'd say: screw that browser. This isn't about an essential page feature missing, heck, it's not even about the page not looking the same across browsers.
This is about allowing the user to change the look of the page. If a user is advanced enough to even know they can do that, then they might also be advanced enough not to use IE.
This feels like optimizing the completely wrong thing - and even changing the spec to accomodate a browser issue (which will never support the new unit anyways).
At this point, there's no advantage to use 1rem instead of 10px, aside of IE9 support.
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[ 3.0 ms ] story [ 34.1 ms ] threadThey work great for @media print styles, though.
If you really want a fixed size in pixels, use pixels, but please don't for anything other than images (and take care with images).
Great post, though.
The unit might as well be 1d (for distance) because the browser can scale the representation of the scenegraph up and down like any vector graphics viewers, think PDF. It's also a small task to offer an alternative CSS for those who want to read the text instead of admiring the spaciousness of the design and the tininess of the fonts.
If a specific browser doesn't support a very specific feature, I'd say: screw that browser. This isn't about an essential page feature missing, heck, it's not even about the page not looking the same across browsers.
This is about allowing the user to change the look of the page. If a user is advanced enough to even know they can do that, then they might also be advanced enough not to use IE.
This feels like optimizing the completely wrong thing - and even changing the spec to accomodate a browser issue (which will never support the new unit anyways).
At this point, there's no advantage to use 1rem instead of 10px, aside of IE9 support.