WebKit CSS extensions - CSS: Cascading Style Sheets
-media-controls-time-remaining-display ::-webkit-media-controls-toggle-closed-captions-button ::-webkit-media-controls-volume-control-container ::-webkit-media-controls-volume-control-hover-background ::-webkit-media-controls-volume-slider ::-webkit-meter-bar ::-webkit-meter-even-less-good-value ::-webkit-meter-inner-element ::-webkit-meter-optimum-value ::-webkit-meter-suboptimum-value -webkit-media-text-track-container ::-webkit-outer-spin-button ::-webkit-progress-bar ::-webkit-progress-inner-element ::-webkit-progress-value ::-webkit-search-cancel-button ::-webkit-search-results-button ::-webkit-slider-runnable-track ::-webkit-slider-thumb note: generally, if there is an invalid pseudo-element or pseudo-class within in a chain or group of selectors, the whole selector list is invalid.