fix no-js pre

threejs/lessons/resources/lesson.css

@@ -42,6 +42,11 @@ pre.prettyprint {
 pre.prettyprint li {
     white-space: pre;
 }
+pre.prettyprint code {
+    color: #CCC;
+    font-family: "Lucida Console", Monaco, monospace;
+    display: block;
+}
 
 /* to handle long words in paragraph */
 p code {