Update understanding/20/use-of-color.html

understanding/20/use-of-color.html

@@ -180,7 +180,7 @@ <h3>Focus on buttons</h3>
          <p>A page has a row of buttons with white text on a medium blue background. When one of the buttons receives keyboard focus, its 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 a change of color is not the only indicator of focus.</p>
             <figure id="figure-buttons">
           <img src="img/buttons.svg" alt="Three buttons with white text on a blue background. When a button receives keyboard focus, the background turns black" width="400" />
-				<figcaption>A row buttons that all have white text on a mid-blue background with a contrast of 5:1. The black button represents a button which has received keyboard focus. The difference of contrast between the focused and the unfocused state of the button's background color is 4.2:1.</figcaption></figure>
+				<figcaption>A row of buttons that all have white text on a mid-blue background with a contrast of 5:1. The black button represents a button which has received keyboard focus. The difference of contrast between the focused and the unfocused state of the button's background color is 4.2:1.</figcaption></figure>
 
    </section>