css selectors

Yesterday, I wrote about what the comma means in CSS.

In doing so, I realized that it’s not actually considered a CSS selector.

What the selectors are is another thing I find myself constantly looking up.

I found MDN’s reference table of selectors a concise summary of the different selectors (copied below).

| Selector | Example | Learn CSS tutorial | | --------------------------- | ----------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ----- | ------------------------------------------------------------------- | | Type selector | h1 { } | Type selectors | | Universal selector | * { } | The universal selector | | Class selector | .box { } | Class selectors | | id selector | #unique { } | ID selectors | | Attribute selector | a[title] { } | Attribute selectors | | Pseudo-class selectors | p:first-child { } | Pseudo-classes | | Pseudo-element selectors | p::first-line { } | Pseudo-elements | | Descendant combinator | article p | Descendant combinator | | Child combinator | p | Child combinator | | Adjacent sibling combinator | h1 + p | Adjacent sibling | | General sibling combinator | h1 ~ p | General sibling | | Tag and Class Combination | p.class | Selects all p elements with a class name of class | | Attribute | [target] | Selects all elements with an attribute of target | | [attribute=value] | [target=_blank] | Selects all elements with target=“_blank” | | [attribute~=value] | [title~=flower] | Selects all elements with a title attribute containing the wor “flower” | | [attribute^=value] | a[href^="https"] | Selects every <a> element whose href attribute value begins with “htps” | | [attribute$=value] | a[href$=".pdf"] | Selects every <a> element whose href attribute value ends with “.pdf” | | [attribute*=value] | a[href*="w3schools"] | Selects every <a> element whose href attribute value contains the substring “w3schools” | | [attribute | =value] | [lang | =en] | Selects all elements with a lang attribute value starting with “en” | | :active | a:active | Selects the active link | | ::after | p::after | Insert something after the content of each <p> element | | ::before | p::before | Insert something before the content of each <p> element | | :checked | input:checked | Selects every checked <input> element | | :default | input:default | Selects the default <input> element | | :disabled | input:disabled | Selects every disabled <input> element | | :empty | p:empty | Selects every <p> element that has no children (including text nodes) | | :enabled | input:enabled | Selects every enabled <input> element | | :first-child | p:first-child | Selects every <p> element that is the first child of its parent | | ::first-letter | p::first-letter | Selects the first letter of every <p> element | | ::first-line | p::first-line | Selects the first line of every <p> element | | :first-of-type | p:first-of-type | Selects every <p> element that is the first <p> element of its parent | | :focus | input:focus | Selects the input element which has focus | | :fullscreen | :fullscreen | Selects the element that is in full-screen mode | | :hover | a:hover | Selects links on mouse over | | :in-range | input:in-range | Selects input elements with a value within a specified range | | :indeterminate | input:indeterminate | Selects input elements that are in an indeterminate state | | :invalid | input:invalid | Selects all input elements with an invalid value | | :lang(language) | p:lang(it) | Selects every <p> element with a lang attribute equal to “it” (Italian) | | :last-child | p:last-child | Selects every <p> element that is the last child of its parent | | :last-of-type | p:last-of-type | Selects every <p> element that is the last <p> element of its parent | | :link | a:link | Selects all unvisited links | | ::marker | ::marker | Selects the markers of list items | | :not(selector) | :not(p) | Selects every element that is not a <p> element | | :nth-child(n) | p:nth-child(2) | Selects every <p> element that is the second child of its parent | | :nth-last-child(n) | p:nth-last-child(2) | Selects every <p> element that is the second child of its parent, counting from the last child | | :nth-last-of-type(n) | p:nth-last-of-type(2) | Selects every <p> element that is the second <p> element of its parent, counting from the last child | | :nth-of-type(n) | p:nth-of-type(2) | Selects every <p> element that is the second <p> element of its parent | | :only-of-type | p:only-of-type | Selects every <p> element that is the only <p> element of its parent | | :only-child | p:only-child | Selects every <p> element that is the only child of its parent | | :optional | input:optional | Selects input elements with no “required” attribute | | :out-of-range | input:out-of-range | Selects input elements with a value outside a specified range | | ::placeholder | input::placeholder | Selects input elements with the “placeholder” attribute specified | | :read-only | input:read-only | Selects input elements with the “readonly” attribute specified | | :read-write | input:read-write | Selects input elements with the “readonly” attribute NOT specified | | :required | input:required | Selects input elements with the “required” attribute specified | | :root | :root | Selects the document’s root element | | ::selection | ::selection | Selects the portion of an element that is selected by a user | | :target | #news:target | Selects the current active #news element (clicked on a URL containing that anchor name) | | :valid | input:valid | Selects all input elements with a valid value | | :visited | a:visited | Selects all visited links |