Style of Todo App

www/todo/todo.less

@@ -25,4 +25,11 @@ body {
 .cryptpad-toolbar {
     padding: 0px;
     display: inline-block;
+}
+#container {
+    display: flex;
+    flex: 1;
+    flex-flow: column;
+    padding: 20px;
+    align-items: center;
 }