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+### Shadow DOM
+
+Shadow DOM allows you to attach hidden DOM (Document Object Model) trees to elements in the normal DOM tree. These subtrees are included in the document rendering, but excluded from the main document DOM tree. A shadow DOM tree will start with a shadow root, to which you can attach any elements you want, just like you would with a regular DOM.
+Examples of shadow DOM uses can already be found in the wild: the `<video>` or `<audio>` elements as well as the simple `<input type="range">` element.