How Does CSS Resolve Conflicting Selectors: A Priority Guide
Oct 24, 2024 am 04:02 AM
CSS Selector Priority: Resolving Conflicts
In the realm of CSS, it's common to have multiple selectors targeting the same element. When this occurs, a question arises: Which selector takes precedence? This is where the concept of selector priority comes into play.
Priority Rules
The CSS specification defines a clear set of rules for determining selector priority:
- !important Rules and Inline Styles Override All: Rules declared with the !important flag and inline styles have the highest priority.
- Specificity: The more specific the selector, the higher its priority. Specificity is calculated based on the number of IDs, classes, and element names used in the selector. For example, #id has a higher specificity than .classname, which has a higher specificity than tagname.
- Declaration Order: If two selectors have the same specificity, the one declared last in the stylesheet wins.
Example
Consider the following example:
<code class="css">#my-id {
color: red;
}
.my-class {
color: blue; /* !important */
}</code>
In this scenario, the selector ".my-class" has the highest priority due to the !important flag. As a result, the element with the ID "my-id" will have its color set to blue, overriding the rule declared in the #my-id selector.
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