A CSS selector selects the HTML element(s) you want to style.
CSS selectors are used to "find" (or select) the HTML elements you want to style.
We can divide CSS selectors into five categories:
Here, all <p> elements on the page will be center-aligned, with a red text color:
The id selector uses the id attribute of an HTML element to select a specific element.
The id of an element is unique within a page, so the id selector is used to select one unique element!
To select an element with a specific id, write a hash (#) character, followed by the id of the element.
The CSS rule below will be applied to the HTML element with id="para1":
The class selector selects HTML elements with a specific class attribute.
To select elements with a specific class, write a period (.) character, followed by the class name.
In this example all HTML elements with class="center" will be red and center-aligned:
The universal selector (*) selects all HTML elements on the page.
The CSS rule below will affect every HTML element on the page:
The grouping selector selects all the HTML elements with the same style definitions.
Look at the following CSS code (the h1, h2, and p elements have the same style definitions):
In this example we have grouped the selectors from the code above: