What is CSS?
CSS (Cascading Style Sheets) is the language used to describe how HTML elements should look — layout, color, typography, spacing, and responsive behavior across screen sizes. "Cascading" refers to how rules from multiple sources (browser defaults, external stylesheets, inline styles) combine with a defined specificity and order of precedence.
Example
.card { border-radius: 12px; padding: 1rem; } styles every element with class "card".
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