CSS Specificity is a concept that is used to determine which style will be applied to an HTML element when multiple styles are competing for the same element. It is based on the order of the CSS rules, the type of selector used, and the number of selectors used. CSS Specificity
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Cascading Style Sheets (CSS) is a style sheet language used for specifying the presentation and styling of a document written in a markup language, such as HTML or XML. CSS is a cornerstone technology of the World Wide Web, alongside HTML and JavaScript.