How does `!important` interact with CSS specificity and the cascading order?

Relationship between !important and CSS Specificity

While CSS specificity dictates the importance of selectors, it does not quantify the weight of the !important directive. This article explores how !important interacts with both specificity and the overall CSS cascade.

Detachment from Specificity

Despite its name, !important has no direct bearing on the specificity point system. It operates solely on the declaration level, influencing the cascading mechanism rather than selector precedence.

Cascading Dominance

The !important directive effectively trumps all specificity factors. If multiple rules apply to the same element, the one with the !important declaration overrides all others.

Specificity Unraveled

While !important can override traditional specificity, it does not completely nullify it. In cases where multiple !important declarations coexist, the rule with the higher specificity still prevails. This is due to the cascading order of styles, where rules applied later take precedence.

Use Cases

Consider the following scenarios:

1. If two declarations for the same property have different importance levels, the one with !important always wins.
2. Among multiple !important declarations, the one in the rule with the highest specificity takes precedence.
3. When two conflicting !important rules have equal specificity, the rule that appears later in the cascading order applies.
4. The presence of an !important declaration trumps the specificity advantage of a more specific selector.
5. In the event of multiple !important declarations, the rule with the higher specificity still governs the outcome.

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