Explain the basic rules of CSS Specificity
CSS specificity determines which CSS rules are applied when multiple rules target the same element. It follows a set of rules to determine the specificity of a selector. Here are the basic rules of CSS specificity:
- Inline Styles: Inline styles have the highest specificity. Styles applied directly to an element using the
styleattribute override all other styles.
- ID Selectors: ID selectors have a higher specificity than class selectors and element selectors. An ID selector is denoted by
#followed by the ID name.
- Class Selectors and Attribute Selectors: Class selectors (e.g.,
.class-name) and attribute selectors have lower specificity than ID selectors but higher specificity than element selectors.
- Element Selectors: Element selectors have the lowest specificity. They target elements based on their tag name (e.g.,
- Combination of Selectors: When multiple selectors are combined, the specificity is calculated based on the sum of the specificity values of the individual selectors. For example, a selector with one ID, two classes, and three element selectors would have a higher specificity than a selector with two classes and four element selectors.
- Importance: The
!importantdeclaration has the highest specificity. When applied to a rule, it overrides all other conflicting styles, regardless of their specificity. However, it is generally recommended to use
!importantsparingly, as it can lead to specificity conflicts and make it harder to maintain and update styles.
In cases where conflicting styles have the same specificity, the style that appears last in the CSS document takes precedence. This is known as the “cascade” in Cascading Style Sheets.
It’s important to understand CSS specificity to ensure that the desired styles are applied correctly. Overusing or relying heavily on IDs or
!important declarations can lead to specificity conflicts and make styles harder to manage and maintain. It’s generally recommended to use selectors with lower specificity, such as classes and element selectors, and leverage the cascade to your advantage by structuring your CSS rules in a logical and organized manner.