CSS !important Override
!important rule overrides that existing property. Sources:
CSS and @ Symbol
These are all known in CSS as at-rules. They’re special instructions for the browser, not directly related to styling of (X)HTML/XML elements in Web documents using rules and properties, although they do play important roles in controlling how styles are applied. @font-face rules define custom fonts for use in your designs that aren’t always available on all... » read more
CSS Class and ID Selectors
You can also define your own selectors in the form of class and ID selectors. The benefit of this is that you can have the same HTML element, but present it differently depending on its class or ID. In the CSS, a class selector is a name preceded by a full stop (“.”) and an ID selector is a... » read more