fix page change anime

@@ -97,15 +97,23 @@ export default {
   transform: translate3d(100%, 0, 0);
 }
 
+.route-view-forword-enter-active {
+  z-index: 2;
+}
+
 .route-view-forword-leave-active {
+  z-index: 1;
   transform: translate3d(-30%, 0, 0);
 }
 
 .route-view-back-enter {
-  z-index: 1;
   transform: translate3d(-30%, 0, 0);
 }
 
+.route-view-back-enter-active {
+  z-index: 1;
+}
+
 .route-view-back-leave-active {
   transform: translate3d(100%, 0, 0);
   z-index: 2;