Style button.playground.

Author: gkellogg

index.html

@@ -197,6 +197,9 @@
   .ds-selector-tabs pre.selected, .ds-selector-tabs table.selected {
     display: block;
   }
+  button.playground {
+    width: 150px;
+  }
   a.playground {
     border-bottom: none;
     text-decoration: none;