HTML and CSS Reference
In-Depth Information
Figure 12-7.
The example for CSS scoped styles
Having these scoped styles within a publisher's markup allows the publisher to specifically style certain portions
of markup that override default settings by style sheets. Keep in mind that CSS scoped styles are very limited in
browser support, but that's expected to change as new browser versions are released. Be sure to keep tabs on this by
CSS Summary
Many of the CSS3 specifications are being modified every day by multiple people on the various working groups, so
it's extremely fluid, and covering all of them is pretty much like hitting a moving target. The browser manufacturers
are highly competitive nowadays (which is a great thing), and they're developing at a much more rapid pace than
most working groups can keep up with. Some of these features are an advantage because they allow you to gain the
most bleeding-edge functions of the browser, and they allow you to experiment and be truly innovative. However, this
can be a disadvantage because oftentimes features are not submitted as standards, so many developers don't know
they're available to access and in which browsers the features operate correctly.
As you know, developing for one browser isn't usually the best approach because many people use a variety of
OSs and browsers with multiple versions, which ultimately means you need to define your reach before starting any
development. This is even more so the case in advertising because clients want their messages everywhere; therefore,
targeting the broadest audience and covering more screens/browsers is an absolute must, which could limit the CSS
features you use. Keep in mind that when using feature detection like Modernizer, when a browser says, “Hey, sure,
I support this feature,” you should do some more testing first. Just because the browser claims it supports a feature
doesn't mean it's performant in an advertising campaign, especially when deployed in conjunction with other
elements on the publisher's page. This is specifically the case for animation, which could burn out the browser quickly
and have everything come to a crashing halt, because repainting and reflowing the screen are costly for performance.
Not
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