HTML Tag Reference HTML Browser Support HTML Event Reference HTML Color Reference HTML Attribute Reference HTML Canvas Reference HTML SVG Reference HTML Character Sets Google Maps Reference CSS CSS Reference CSS Browser Support CSS Selector Reference Bootstrap 3 Reference Bootstrap 4 Reference W3.CSS Reference Icon Reference Sass Reference XPCOM Reference. Although it does mention that if the parent element is a picture element, 'The media attributes may also be present", whereas media attributes are not mentioned if the parent element is another type of media element. The table below lists all HTML attributes and what elements they can be used within: Attribute Belongs to Description; accept Specifies the types of files that the server accepts (only for type="file") accept-charset