Use !important should override styles that cannot be modified directly, such as third-party or uncontrollable inline styles, if necessary. 1. Applicable scenarios: inline styles injected by CMS or framework, third-party styles that cannot be rewrited later, and quick coverage during browser debugging. 2. Influence mechanism: mandatory rules are preferred, breaking the normal specificity level. If both parties use it, return to normal specificity judgment. 3. Potential risks: Increase debugging difficulty, reduce maintenance, and encourage bad habits, leading to more important superposition to form chaos. 4. Best practices: only use when there is no other solution, add comments to explain the reasons, avoid large-scale project abuse, and prioritize testing of non-important solutions. The overall CSS strategy should be examined when used frequently.

You should use !important in CSS only when you absolutely need to override another style that you can't change directly—like third-party styles or inline styles you don't control. It's a powerful tool, but it comes with trade-offs, especially when it comes to selector specificity and maintenance.

When !important is actually useful

There are a few real-world scenarios where !important makes sense:

• You're working with a CMS or framework that injects inline styles you can't modify.
• You're overriding a third-party stylesheet (like a plugin) and can't re-declare the style later in the cascade.
• You're debugging or doing quick overrides in browser dev tools.

In these cases, !important helps you force your style to take precedence without restructuring the entire stylesheet.

How !important affects specific

Normally, CSS specific works by weighing selectors: IDs > classes/attributes/pseudo-classes > elements. But !important jumps over all of that.

When two rules conflict:

• If one has !important , it wins—even if its selector is less specific.
• If both have !important , then normal specific rules apply again.

So using !important can make your CSS harder to predict and debug because it breaks the expected cascade and specific flow.

Why overusing !important is risky

It might seem like a quick fix, but here's what can go wrong:

• Harder to debug : Styles stop behaving as expected, and tracing overrides becomes messy.
• Maintainability drops : Future developers (or even your future self) may struggle to understand why something isn't changing.
• Encourages bad habits : instead of fixing root issues (like poor selector structure or incorrect load order), people just slap on !important .

This often leads to a snowball effect—more !important s added to fight earlier ones, creating a tangled mess.

Best practices for using !important

If you do use it, keep it under control:

• Only use it when no other method will work.
• Keep a comment nearby explaining why it's there.
• Avoid using it in large-scale projects unless truly necessary.
• Test without it first—maybe you just need a better selector or to adjust load order.

A good rule of thumb: if you find yourself using !important often, it's time to review your CSS strategy.

Basically that's it.

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