CSS stands for cascadind style sheets and cascading simply means multiple styles can be applied or multiple rules can be applied to the same element. Now this rules may lead to conflicts though. To resolve such conflicts CSS knows a concept called specificity and there are clear rules included in the CSS specification that define how such conflict should be resolved and which type of selector has a higher specificity.
ReadWhat's a rule in CSS? A rule in CSS is a combination of selector ("WHAT to style") and declaration ("HOW to style it").
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