CSS selectors are used to pick up HTML element and then we can add styles.
A CSS selector is the part of a CSS rule set.
The following table lists the basic CSS selectors.
| Selector | Example | Example description | CSS |
|---|---|---|---|
| .class | .footer | Selects all elements with class="footer" | 1 |
| #id | #footer | Selects the element with id="footer" | 1 |
| * | * | Selects all elements | 2 |
| element | div | Selects all <div> elements | 1 |
The following table lists the Combinator CSS selectors.
We can use the combinator selector we can do the selection based on the relations.
| Selector | Example | Example description | CSS |
|---|---|---|---|
| ele,ele | div, h1 | Selects all <div> and all <h1> | 1 |
| ele ele | div h1 | Selects all <h1> inside <div> | 1 |
| ele > ele | div > h1 | Selects all <h1> whose the parent is a <div> | 2 |
| ele+ele | div + h1 | Selects all <h1> placed immediately after <div> elements | 2 |
| ele~ele | p ~ div | Selects <div> preceded by a <p> element | 3 |
The following table has the attribute selectors. We can use attribute selectors to select HTML elements by attribute value.
| Selector | Example | Example description | CSS |
|---|---|---|---|
| [attr] | [href] | Selects all elements with a href attribute | 2 |
| [attr=value] | [title=message] | Selects all elements with title="message" | 2 |
| [attr~=value] | [title~=tooltip] | Selects all elements with title attribute which has word "tooltip" | 2 |
| [attr|=value] | [lang|=en] | Selects all elements with lang attribute whose value is "en" | 2 |
| [attr^=value] | a[href^="http"] | Selects <a> element whose href attribute begins with "http" | 3 |
| [attr$=value] | a[href$=".htm"] | Selects <a> element whose href attribute ends with ".htm" | 3 |
| [attr*=value] | a[href*="htm"] | Selects <a> element whose href attribute contains the substring "htm" | 3 |
A pseudo-class uses colon character(s) to identify a pseudo-state that an element might have. For example, we can select active state for anchor links.
| Selector | Example | Example description | CSS |
|---|---|---|---|
| :active | a:active | Select the active links | 1 |
| ::after | div::after | Insert content after every <div> element | 2 |
| ::before | div::before | Insert content before the content of every <div> element | 2 |
| :checked | input:checked | Selects checked <input> element | 3 |
| :disabled | input:disabled | Selects disabled <input> element | 3 |
| :empty | div:empty | Selects <div> element withno children (including text nodes) | 3 |
| :enabled | input:enabled | Selects enabled <input> element | 3 |
| :first-child | div:first-child | Selects every <div> element that is the first child | 2 |
| ::first-letter | p::first-letter | Selects the first letter of <p> element | 1 |
| ::first-line | p::first-line | Selects the first line of <p> element | 1 |
| :first-of-type | p:first-of-type | Select the first occurence of a <p> element within its container. | 3 |
| :focus | input:focus | Selects the input element with focus | 2 |
| :hover | a:hover | Selects links on mouse over | 1 |
| :in-range | input:in-range | Selects input elements whose value is within a range | 3 |
| :invalid | input:invalid | Selects input elemets with invalid value | 3 |
| :lang(language) | p:lang(en) | Selects <p> element with a lang attribute equal to "en" (English) | 2 |
| :last-child | p:last-child | Selects <p> element that is the last child within its container | 3 |
| :last-of-type | p:last-of-type | Selects <p> element that is the last <p> element within its container | 3 |
| :link | a:link | Selects all unvisited links | 1 |
| :not(selector) | :not(div) | Selects element that is not a <div> element | 3 |
| :nth-child(n) | p:nth-child(2) | Selects <p> element that is the second child within its container | 3 |
| :nth-last-child(n) | p:nth-last-child(2) | Selects <p> element that is the second child counting from the last within its container | 3 |
| :nth-last-of-type(n) | p:nth-last-of-type(2) | Selects <p> element that is the second <p> counting from the last child | 3 |
| :nth-of-type(n) | p:nth-of-type(2) | Selects <p> element that is the second <p> element | 3 |
| :only-of-type | p:only-of-type | Selects every <p> element that is the only <p> element within its container | 3 |
| :only-child | p:only-child | Selects <p> element that is the only child within its container | 3 |
| :optional | input:optional | Selects input elements with no "required" attribute | 3 |
| :out-of-range | input:out-of-range | Selects input elements whose value is outside a range | 3 |
| :read-only | input:read-only | Selects input elements with the "readonly" attribute | 3 |
| :read-write | input:read-write | Selects input elements whose "readonly" attribute is not set | 3 |
| :required | input:required | Selects input elements with "required" attribute | 3 |
| :root | :root | Selects the document's root element | 3 |
| ::selection | ::selection | Selects the portion of an element that is selected | |
| :target | #id:target | Selects the current active #id element | 3 |
| :valid | input:valid | Selects input elements with a valid value | 3 |
| :visited | a:visited | Selects all visited links | 1 |