Update IPython Notebook template

- Improve to handle err class
- Improve pandoc support

lesson.css

@@ -3,6 +3,31 @@ pre {
     color: inherit;
 }
 
+/* Work around to issue when create EPUB with pandoc for IPython Notebook
+ * template.
+ */
+div.out {
+  display: block;
+  padding: 9.5px;
+  margin-bottom: 10px;
+  font-size: 13px;
+  line-height: 20px;
+  word-break: break-all;
+  word-wrap: break-word;
+  background-color: #f5f5f5;
+  border: 1px solid #ccc;
+  border: 1px solid rgba(0, 0, 0, 0.15);
+  -webkit-border-radius: 4px;
+     -moz-border-radius: 4px;
+          border-radius: 4px;
+}
+
+div.out pre {
+    padding: 0px;
+    margin: 0px;
+    border: 0px;
+}
+
 /* Comments in code. */
 .comment {
     color: purple;