fix: Format example blocks

books/core/50.html

@@ -36,10 +36,9 @@
   the same operation together; the Game Master always has final say on whether a
   Group Check is possible or should be performed.
 </p>
-<h3>Example:</h3>
-<p>
-  Three heroes are trying to persuade the Great Owl to grant them access to her
-  ancient library. The leader performs a DL 13
+<p class="example">
+  <strong>Example: </strong>Three heroes are trying to persuade the Great Owl to
+  grant them access to her ancient library. The leader performs a DL 13
   <span class="check">【INS + WLP】</span> Check, and the two supporting
   characters perform <span class="check">【INS + WLP】</span> Checks with a
   Difficulty of 10. They both succeed, and one has a strength 2 Bond towards the