[css-color-5][editorial] Update changes

Author: svgeesus

css-color-5/Overview.bs

@@ -3518,7 +3518,9 @@ This specification adds a way to ensure adequate contrast for text whose backgro
 </h3>
 
 <ul>
-	<!-- to 17 March 2025 -->
+	<!-- to 26 March 2025 -->
+	<li>Defined that in color-mix(), if the percentages sum to zero, return transparent</li>
+	<li>Properly exported the term "required conversion"</li>
 	 <li>Clarified that component keywords can return ''none'' as well as a number</li>
 	 <li>Added examples of serialization of nested color functions</li>
 	 <li>Defined edge cases of color-mix() with calc, by WG resolution</li>