Question about best practice CSS styling controls

Hi,

in .net controls tend to be styled using in-line styling. You can set styling in the properties section of the Visual Studio IDE as opposed to adding a class id to it. But doesn't this go against best practice for CSS. CSS should normally all be in a separate stylesheet shouldn't it?

So what do the pros do about this? Or would it simply be too time consuming to create separate styling for the controls in a separate stylesheet?

Thanks!
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