code: def css(self, name=None):
          
          filepaths = copy.copy(settings.CODEMIRROR_BASE_CSS)
  
          configs = self.get_configs(name)
          names = sorted(configs)
  
          # Process themes
          for name in names:
              opts = configs[name]
              for item in opts.get('themes', []):
                  resolved = self.resolve_theme(item)
                  if resolved not in filepaths:
                      filepaths.append(resolved)
  
          # Then process extra CSS files
          for name in names:
              opts = configs[name]
              for item in opts.get('extra_css', []):
                  if item not in filepaths:
                      filepaths.append(item)
  
          return filepaths
docs: Returns all needed CSS filepaths for given config name (if
          given) or every registred config instead (if no name is given).
  
          Keyword Arguments:
              name (string): Specific config name to use instead of all.
  
          Returns:
              list: List of CSS file paths.