Origins of a style sheet and the CSS cascadeUser agent style sheets (default browser styles)User style sheetsUser style sheet support in web browsersAttributes and characteristics of author style sheetsExternal and embedded style sheetsNaming and specifying media and character encoding detailsInline stylesSelectors: from simple to complex to surgicalSimple selectorsType selectorsUniversal type selectorAttribute selectorsID and class selectorsPseudo-classesPseudo-elementsUsing combinatorsDescendant combinatorChild combinatorAdjacent sibling combinatorGeneral sibling combinatorProperty values and unitsKeywords and font namesNumbersLengthsPercentagesTime, frequencies, and anglesStringsFunctional notationURI references: the url() functionColor functions: rgb(), rgba(), hsl(), and hsla()Generated content functions: attr() and counter()Basic math for computing lengths: the calc() functionVisual rendering and formatting conceptsCSS boxes and document flowCSS positioning schemesStatic positioningRelative positioningAbsolute positioningFixed positioningFloated CSS boxesStacking contextsCSS box models: content-box model vs. border-box modelSummary