Shadow DOM | CSS: Presentation Layer
Standards Based Development
Shadow dom gives you access to the internals of browser widgets; the buttons in a video element that the browser provides when the controls attribute is specified. Shadow dom is part of the Web Components specification.
Shadow dom specifies that all html elements must behave as if they already have an existing, ua-provided shadow tree, which in turn allows the author-created shadow trees to properly override (and even include) those ua-provided shadow trees.
Dimitri Glazkov
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