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Frequently Asked Questions

What is the difference between `display: none;` and `visibility: hidden;` in CSS?

Both hide elements, but `display: none;` removes the element from the layout entirely and its content isn't rendered. Conversely, `visibility: hidden;` hides the element visually but still occupies its space within the document flow, meaning other elements reflow to fill that space.

Can you explain how CSS specificity works when multiple rules target the same element?

CSS specificity is determined by a cascading system prioritizing different factors: Inline styles have the highest priority, followed by IDs, classes, and then element selectors. More specific selectors (e.g., using an ID) will override less specific ones (e.g., using a class) when multiple rules apply to the same element.

What are 'shadow DOM's and why would I use them?

'Shadow DOM' allows you to create encapsulated, isolated CSS and JavaScript within an element. This prevents conflicts with global styles or scripts attached to the main document, enhancing modularity and simplifying development of complex components by limiting scope.