Syntax editor: minor CSS tweak to resemble Minibar more

src/www/syntax-editor/editor.css

@@ -80,6 +80,8 @@ body.syntax-editor {
   /* display: inline-block; */
   /* margin-left: 0.5em; */
   margin-top: 0.3em;
+  border: 3px solid #e0e0e0;
+  padding: 5px;
   }
 
 #linearisations