some changes

src/main/resources/templates/detail.html

@@ -37,7 +37,7 @@
     </section>
     <footer class="col-md-12 text-center">
         <span class="col-md-12">
-            <button class="btn btn-primary" th:onclick="'window.location.pathname=\'' + @{/} + '\''">Volver</button>
+            <a class="btn btn-primary" th:href="@{/}">Volver</a>
         </span>
         <span>2018</span>
     </footer>