Class selectors

A class selector is a type of CSS selector that selects elements that have a specific class attribute. The class attribute is a custom attribute that you can add to HTML elements to group them together.

To select elements with a specific class, you use a period (.) followed by the class name. For example, the selector .my-class selects all elements that have the class my-class.

Here is an example of how to use a class selector to style a web page:

.my-class {
  color: red;
  font-size: 2em;
}

To add a class to an element write:

<div class="my-class"></div>

This CSS rule will style all elements that have the class my-class to be red and have a font size of 2em.