The CSS.supports() static methods returns a Boolean value indicating if the browser supports a given CSS feature, or not.
The CSS Object Model is a set of APIs allowing to manipulate CSS from JavaScript. It is the pendant of DOM and HTML APIs, but for CSS. It allows to read and modify CSS style dynamically.
The CSS Object Model (CSSOM), part of the DOM, exposes specific interfaces allowing manipulation of a wide amount of information regarding CSS. Initially defined in the DOM Level 2 Style recommendation, these interfaces forms now a specification, CSS Object Model (CSSOM) which aims at superseding it.
The CSSMediaRule is an interface representing a single CSS @media rule. It implements the CSSConditionRule interface, and therefore the CSSGroupingRule and the CSSRule interface with a type value of 4 (CSSRule.MEDIA_RULE).
CSSPageRule is an interface representing a single CSS @page rule. It implements the CSSRule interface with a type value of 6 (CSSRule.PAGE_RULE).
The CSSRule interface represents a single CSS rule. There are several types of rules, listed in the Type constants section below.
The CSSStyleSheet interface represents a single CSS style sheet. It inherits properties and methods from its parent, StyleSheet.
The StyleSheet.disabled property indicates whether the style sheet is prevented from applying to the document. A style sheet may be disabled by manually setting this property to true or if it's an inactive alternative style sheet. Note that disabled == false does not guarantee the style sheet is applied (it could be removed from the document, for instance).
media specifies the intended destination medium for style information.
The StyleSheetList interface represents a list of StyleSheet.
CSS
The CSS interface holds useful CSS-related methods. No object with this interface are implemented: it contains only static methods and therefore is a utilitarian interface.
An object implementing the CSSConditionRule interface represents a single condition CSS at-rule, which consists of a condition and a statement block. It is a child of CSSGroupingRule.
An object implementing the CSSGroupingRule interface represents any CSS at-rule that contains other rules nested within it.
CSSStyleRule represents a single CSS style rule. It implements the CSSRule interface with a type value of 1 (CSSRule.STYLE_RULE).
The CSSSupportsRule interface describes an object representing a single CSS @supports at-rule. It implements the CSSConditionRule interface, and therefore the CSSRule and CSSGroupingRule interfaces with a type value of 12 (CSSRule.SUPPORTS_RULE).
The Element.getBoundingClientRect() method returns the size of an element and its position relative to the viewport.
Returns the location of the stylesheet.
ownerNode returns the node that associates this style sheet with the document.
Returns the stylesheet that is including this one, if any.