What\'s the Difference Between \".\" (Class Selector) and \"#\" (ID Selector) in CSS?

CSS Selector Syntax: Delving into the Roles of "." and "#"

In the realm of CSS, the ubiquitous "." (dot) and "#" (hash) symbols play distinct roles when defining style sets for HTML elements. Understanding their differences is crucial for effective and precise styling.

Class Selector vs. ID Selector

• " . ": Denotes a class selector. It targets all elements sharing a specific class attribute. Multiple classes can be assigned to an element, allowing for flexible styling based on shared characteristics.
• " # ": Represents an ID selector. It identifies a unique element based on its ID attribute. By definition, an ID value must be exclusive within a document, targeting only one specific element.

Typical Applications

Class selectors are commonly used for generic styling applicable to multiple elements, such as headings or form fields. ID selectors are reserved for unique elements, like page layouts or navigational elements.

Specificity

Within CSS, selectors have varying degrees of specificity. ID selectors possess higher specificity than class selectors. Consequently, any style declarations associated with an ID selector will override conflicting styles applied through class selectors.

Example:

#sidebar {
  /* Styles for the single element with>

Conclusion

Grasping the distinction between class selectors (".") and ID selectors ("#") is essential for effective CSS styling. They enable precise targeting of HTML elements, allow for flexibility and reuse, and determine the precedence of conflicting style definitions. By wielding this knowledge, developers can craft elegant and robust web designs.

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