1.4.1 Use of color: adding examples to understanding text

understanding/20/use-of-color.html

@@ -167,8 +167,12 @@ <h2>Examples of Use of Color</h2>
                element. A legend shows the color and number for each type of element. Sighted users who
                cannot perceive all the color differences can still understand the image by relying on
                the numbers.</dd>
+         <dt>Focus on links</dt>
+         <dd>A page has text links in blue that have a contrast of 3:1 to the surrounding text. When these links receive keyboard focus, they are shown in a darker color. In addition, they are underlined, so the change of color is not the only indicator of focus.</dd>
+      </dl>
+         <dt>Focus on buttons</dt>
+         <dd>A page has buttons with white text on a medium blue background. When the buttons receive keyboard focus, their background turns black. The difference of contrast between the unfocused and the focused button background is above 3:1. This difference of contrast means that the change of color is not the only indicator of focus.</dd>
       </dl>
-
    </section>
 
    <section id="resources">