Fixes heinous typo in horizontal flip out

src/modules/transition.less

@@ -26,6 +26,7 @@
 *******************************/
 
 .ui.animating.transition {
+  display: block;
   backface-visibility: hidden;
   transform: translateZ(0);
 }
@@ -149,7 +150,7 @@
 
 
 /*--------------
-      Slide
+     Slide
 ---------------*/
 
 .ui.slide.down.transition.in {
@@ -198,7 +199,7 @@
 *******************************/
 
 /*--------------
-  Emphasis
+    Emphasis
 ---------------*/
 
 /* Flash */
@@ -293,11 +294,11 @@
 @keyframes horizontalFlipOut {
   0% {
     transform: rotateY(0deg);
-    opacity: 0;
+    opacity: 1;
   }
   100% {
     transform: rotateY(90deg);
-    opacity: 1;
+    opacity: 0;
   }
 }