Update Overview.bs

Author: tabatkins

css-size-adjust-1/Overview.bs

@@ -151,7 +151,7 @@ Size adjustment control: the 'text-size-adjust' property {#adjustment-control}
 
   <pre class=propdef>
       Name: text-size-adjust
-      Value: auto | none | &lt;percentage&gt;
+      Value: auto | none | <<percentage>>
       Initial: auto
       Applies to: all elements
       Inherited: yes
@@ -169,7 +169,7 @@ Size adjustment control: the 'text-size-adjust' property {#adjustment-control}
     <dt><dfn>&lt;percentage&gt;</dfn></dt>
       <dd>When displaying on a small device, renderers must not do size adjustment but instead the computed value of 'font-size' must be multiplied by this percentage.
       <p class="note">Note: This means that 'text-size-adjust: 100%;' is equivalent to 'text-size-adjust: none;'.</p>
-      <p>Negative values are not allowed.</p></dd>
+      <p>Negative values are invalid.
   </dl>
 
   Issue: "Small device" is not well defined. We should clearly specify