ref(css): use more varied defaults

This is to make the text appear more obvious for skimming.

colors/highlite.vim

@@ -434,17 +434,18 @@ local highlight_groups = {
 	cssAttrComma       = 'Noise',
 	cssAttrRegion      = 'Keyword',
 	cssBraces          = 'Delimiter',
-	cssClassName = 'Structure',
+	cssClassName       = 'Identifier',
 	cssClassNameDot    = 'Noise',
+	cssFlexibleBoxAttr = 'cssAttr',
 	cssFunctionComma   = 'Noise',
+	cssImportant       = 'Exception',
 	cssNoise           = 'Noise',
 	cssProp            = 'Label',
 	cssPseudoClass     = 'Special',
-	cssPseudoClassId = 'Operator',
+	cssPseudoClassId   = 'cssSelectorOp',
 	cssSelectorOp      = 'Operator',
-	cssTagName = 'htmlTagName',
-	cssTagName = 'Type',
-	cssUnitDecorators = 'StorageClass',
+	cssTagName         = 'Structure',
+	cssUnitDecorators  = 'Type',
 	scssAmpersand      = 'Special',
 	scssAttribute      = 'Label',
 	scssBoolean        = 'Boolean',