[css-color-4] fix bs syntax

Author: svgeesus

css-color-4/Overview.bs

@@ -4619,10 +4619,10 @@ Color space for interpolation</h3>
 		* 'filter'
 		* 'animation'
 		* 'transition'
-		* [[color-mix()]]
+		* ''color-mix()''
 	</div>
 
-	These features are collectively termed the<dfn>host syntax</dfn>.
+	These features are collectively termed the <dfn>host syntax</dfn>.
 	The host syntax should define
 	what the default interpolation space should be for each case,
 	and optionally provide syntax for authors to override this default.