Shadow DOM | Create Lightning Web Components
A component can define zero or more slots in its shadow DOM. Slots can be empty or provide fallback content. If the user doesn't provide light DOM content, the slot renders its fallback content.
ShadowRoot: mode property - Web APIs | MDN
In web development, understanding the inner workings of the Document Object Model (DOM) is crucial. Two concepts that often come up in discussions about DOM are Virtual DOM and Shadow DOM.
The Web Component Slot element - HTML - MDN Web Docs
slottedとは、web componentsで作ったcustom elementsのslot内部に入る要素に対してスタイルを適用するものです。 shadow DOM内で使われる時のみ::slottedは機能します。.