Web Development web frontend styling

What is CSS?

Definition

CSS (Cascading Style Sheets) is a stylesheet language that controls the visual presentation of HTML documents. It defines colors, layouts, fonts, spacing, animations, and responsive designs through selectors and property-value rules.

Why It Matters

CSS turns HTML structure into visual design. Modern CSS features (flexbox, grid, custom properties, container queries) eliminate the need for most JavaScript layout hacks. CSS minification reduces file size and improves page load speed.

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