What is DOM (Document Object Model) and how is it linked to CSS?

The Document Object Model (DOM) is a programming interface for web documents. It represents the page so that programs can change the document structure, style, and content. The DOM represents the document as nodes and objects, which allows programming languages to interact with the page[1][2]. Essentially, it is a model loaded in the browser that represents the document as a node tree, where each node represents part of the document, such as an element, text string, or comment[1].

The DOM is crucial in web development because it provides a structured, object-oriented way of representing the web page, which can be manipulated with a scripting language like JavaScript. This manipulation includes changing the structure of the HTML document, modifying styles, and responding to user events[2][3].

CSS, or Cascading Style Sheets, is a style sheet language used for describing the presentation of a document written in HTML. CSS dictates how elements should be rendered on screen, on paper, or in other media[3].

The link between the DOM and CSS is through the CSS Object Model (CSSOM), which is analogous to the DOM for HTML. The CSSOM is a map of all the CSS selectors and their corresponding properties that the browser uses to apply styles to the DOM. When a web page is loaded, the browser creates the DOM for the HTML and the CSSOM for the CSS. The browser then combines the DOM and the CSSOM to render the page[3][13].

The DOM is not only a representation of the HTML structure but also includes the visual styling from CSS. When you use JavaScript to manipulate the DOM, you can also change th...