This is a quick reference list of CSS pseudo-classes used to select HTML elements for styling.

• CSS – :active Selector
  The :active selector is used to select the active link, which becomes active when it’s clicked.
• CSS – :checked Selector
  The :checked selector matches every checked input element for radio buttons, checkboxes, and option elements.
• CSS – :disabled Selector
  The :disabled selector matches all disabled form elements.
• CSS – : empty Selector
  The :empty selector selects empty HTML elements, which means an element without any child elements or text.
• CSS – :enabled Selector
  The :enabled selector matches all enabled form elements.
• CSS – :first-child Selector
  The :first-child selector selects all HTML elements of a specified type that are also the first child of their parent element.
• CSS – :first-of-type Selector
  The :first-of-type selector selects all elements that are the first child of a specified type of their parent element.
• CSS – :focus Selector
  The :focus selector selects the element that currently has focus.
• CSS – :hover Selector
  The :hover selector selects elements when you mouse over them, and is commonly used for links and images with links, but can be used on any element.
• CSS – :in-range Selector
  The :in-range selector selects elements with a value that is within a specified range, and only works for input elements with min/max attributes.
• CSS – :invalid Selector
  The :invalid selector selects form elements with a value that does not validate according to the element’s settings.
• CSS – :lang Selector
  The :lang selector is used to select elements with a lang attribute with a specified value (e.g., lang = “en” or lang = “en-us”).
• CSS – :last-child Selector
  The :last-child selector selects all HTML elements of a specified type that are also the last child of their parent element.
• CSS – :last-of-type Selector
  The :last-of-type selector selects all elements that are the last child of a specified type of their parent element.
• CSS – :link Selector
  The :link selector is used to select unvisited links, and will not style links you have already visited.
• CSS – :not() Selector
  The :not() selector selects all elements except the specified element.
• CSS – :nth-child() Selector
  The :nth-child() selector selects all specified elements that are the nth child of their parent, regardless of all the children’s types.
• CSS – :nth-last-child() Selector
  The :nth-last-child() selector selects all specified elements that are the nth child of their parent counting from the last child.
• CSS – :nth-last-of-type() Selector
  The :nth-last-of-type() selector selects all elements that are the nth child of a specified type, of their parent, counting from the last child.
• CSS – :nth-of-type() Selector
  The :nth-of-type() selector selects all elements that are the nth child of a specified type, of their parent.
• CSS – :only-child Selector
  The :only-child selector selects every element that is the only child of its parent. If the parent has multiple child elements, it will NOT be selected.
• CSS – :only-of-type Selector
  The :only-of-type selector selects every element that is the only child of its type, of its parent.
• CSS – :optional Selector
  The :optional selector selects form elements which are optional (those without the required attribute).
• CSS – :out-of-range Selector
  The :out-of-range selector selects elements with a value that is NOT within a specified range, and only works for input elements with min/max attributes.
• CSS – :read-only Selector
  The :read-only selector selects form inputs which are “readonly” (those with a “readonly” attribute).
• CSS – :read-write Selector
  The :read-write selector selects form inputs which are “readable” and “writeable” (those with no “readonly” or “disabled” attributes).
• CSS – :required Selector
  The :required selector selects form inputs which are required (those with the required attribute).
• CSS – :root Selector
  The :root selector matches the document’s root element, which is always the HTML element.
• CSS – :target Selector
  The :target selector selects the current active target anchor element on the page (the element being linked to).
• CSS – :valid Selector
  The :valid selector selects form inputs with a value that properly validates according to the element’s settings.
• CSS – :visited Selector
  The :visited selector is used to select already visited links.