2015
6 featuresThe :nth-of-type() and :nth-last-of-type() CSS functional pseudo-classes match elements based on their position among siblings of the same type. The :first-of-type, :last-of-type, and :only-of-type pseudo-classes match the first, last, and only elements of its type.
The form validity CSS pseudo-classes match <form> elements based on the constraints of a form field, such as validity (:valid, :invalid, :in-range, :out-of-range) and necessity (:optional or :required).
The @namespace CSS rule sets a default namespace or namespace prefix. Namespace prefixes allow CSS selectors to distinguish elements with the same name but different document types, such as the HTML <a> element and the SVG <a> element.
The ::first-letter CSS pseudo-element selects the first letter in an element for styling.
The ::first-line CSS pseudo-element selects the first line of text in an element for styling.
The :nth-child() and :nth-last-child() CSS functional pseudo-classes match elements based on their index within a list of elements. The :first-child and :last-child pseudo-classes match the first and last element in a list, and the :only-child pseudo-class matches an element with no siblings.
Limited Availability
10 featuresThe s identifier in a CSS attribute selector matches attribute values case-sensitively in document languages like HTML where attribute values are case-insensitive.
The :has-slotted CSS pseudo-class matches <slot> elements where the fallback content is not shown. The pseudo-class matches any slotted content, including white space, text nodes, or elements.
The ::spelling-error and ::grammar-error CSS pseudo-elements match text that is highlighted as misspelled and grammatically incorrect, respectively.
The text-decoration CSS property in a ::selection rule sets the underline and other text decoration styles on the text a user has highlighted.
The :past and :future CSS pseudo-classes match prior or upcoming text track cues during media playback.
The :host-context() CSS pseudo-class selects the containing element of the shadow tree in which it is used if that element or an ancestor matches the provided selector.
The ::selection CSS pseudo-element selects text a user has highlighted.
The :first, :left, and :right pseudo-classes select pages based on their position in sequence after pagination.
The :heading and :heading() CSS pseudo-classes match headings of varying levels. The :heading pseudo-class matches any heading (<h1> through <h6>). The :heading() selector matches any of the given levels. For example, :heading(1, 2) matches headings level 1 and 2.
The :target-within CSS pseudo-class matches the element with an ID matching the URL fragment and its ancestors.