# CSS selectors A to Z

CSS selectors A to Z: 34 terms, each with what it does and a link to its full page.

Updated: October 29, 2026

A **selector** is the part of a CSS rule that says which elements the rule styles: `p` styles every paragraph, `.intro` every element with the class intro, `nav a` every link inside a nav.

Here is every CSS selector in the glossary, A to Z, with the pattern you type in the Syntax column. Pick a letter to jump down the list, or pick a selector to read its full page with an example.

## A

- [`:active`](https://www.ask-codey.com/glossary/active), `a:active`: Styles an element while it is being pressed.
- [Adjacent sibling combinator](https://www.ask-codey.com/glossary/adjacent-sibling-combinator), `h2 + p`: The + between selectors: matches the element right after another.
- [`::after`](https://www.ask-codey.com/glossary/after), `.price::after`: Adds generated content at the end of an element.
- [Attribute selector](https://www.ask-codey.com/glossary/attribute-selector), `input[type="email"]`: Selects elements by an attribute, written in \[brackets\].

## B

- [`::before`](https://www.ask-codey.com/glossary/before), `.note::before`: Adds generated content at the start of an element.

## C

- [`:checked`](https://www.ask-codey.com/glossary/checked-css), `input:checked`: Styles checkboxes and radio buttons that are selected.
- [Child combinator](https://www.ask-codey.com/glossary/child-combinator), `ul > li`: The > between selectors: matches direct children only.
- [Class selector](https://www.ask-codey.com/glossary/class-selector), `.intro`: Starts with a dot and selects elements with that class.
- [CSS rule](https://www.ask-codey.com/glossary/css-rule), `p { color: gray; }`: A selector plus a block of declarations: which elements, and how they look.

## D

- [Descendant combinator](https://www.ask-codey.com/glossary/descendant-combinator), `nav a`: A space between selectors: matches elements anywhere inside another.
- [`:disabled`](https://www.ask-codey.com/glossary/disabled-css), `button:disabled`: Styles form controls that are switched off.

## F

- [`:first-child`](https://www.ask-codey.com/glossary/first-child), `li:first-child`: Selects an element that is the first child of its parent.
- [`:focus`](https://www.ask-codey.com/glossary/focus), `input:focus`: Styles the element that has keyboard focus.
- [Functional pseudo-class](https://www.ask-codey.com/glossary/functional-pseudo-class), `li:not(.sold-out)`: A pseudo-class that takes selectors in brackets, like :not().

## G

- [General sibling combinator](https://www.ask-codey.com/glossary/general-sibling-combinator), `h2 ~ p`: The ~ between selectors: matches every later sibling.

## H

- [`:has()`](https://www.ask-codey.com/glossary/has), `.card:has(img)`: Styles an element based on what it contains.
- [`:hover`](https://www.ask-codey.com/glossary/hover), `a:hover`: Styles an element while the mouse is over it.

## I

- [ID selector](https://www.ask-codey.com/glossary/id-selector), `#main`: Starts with # and selects the one element with that id.
- [`:is()`](https://www.ask-codey.com/glossary/is), `:is(h1, h2, h3)`: Matches any selector in its list.

## L

- [`:last-child`](https://www.ask-codey.com/glossary/last-child), `li:last-child`: Selects an element that is the last child of its parent.

## M

- [`::marker`](https://www.ask-codey.com/glossary/marker), `li::marker`: Styles the bullet or number of a list item.

## N

- [`:not()`](https://www.ask-codey.com/glossary/not), `button:not(.primary)`: Matches elements that don't match the selector inside.
- [`:nth-child()`](https://www.ask-codey.com/glossary/nth-child), `tr:nth-child(even)`: Selects children by position, like odd rows or every third item.

## P

- [`::placeholder`](https://www.ask-codey.com/glossary/placeholder-css), `input::placeholder`: Styles the hint text in an empty input.
- [Pseudo-class](https://www.ask-codey.com/glossary/pseudo-class), `button:hover`: Styles an element in a state, like :hover, with one colon.
- [Pseudo-element](https://www.ask-codey.com/glossary/pseudo-element), `p::first-line`: Styles part of an element, or adds decoration, with two colons.

## S

- [Selector](https://www.ask-codey.com/glossary/selector), `nav a.active`: The part of a rule that picks which elements to style.
- [Selector list](https://www.ask-codey.com/glossary/selector-list), `h1, h2, h3`: Several selectors separated by commas, sharing one set of styles.
- [Selector matching](https://www.ask-codey.com/glossary/selector-matching): Browsers read selectors right to left: the last part first.
- [Specificity](https://www.ask-codey.com/glossary/specificity): How precise a selector is; the more specific rule wins.

## T

- [Type selector](https://www.ask-codey.com/glossary/type-selector), `p`: Selects every element with a given tag name, like p or img.

## U

- [Universal selector](https://www.ask-codey.com/glossary/universal-selector), `*`: The \* selector: matches every element.

## V

- [`:visited`](https://www.ask-codey.com/glossary/visited), `a:visited`: Styles links the user has already opened.

## W

- [`:where()`](https://www.ask-codey.com/glossary/where-css), `:where(ul, ol) li`: Like :is() but with zero specificity, so easy to override.

[Every CSS term, by level](https://www.ask-codey.com/glossary/subjects/css)

Source: https://www.ask-codey.com/glossary/reference/css/selectors