Add hover-state for emoji in emoji-picker

CHANGELOG

@@ -45,6 +45,7 @@ v 8.3.0 (unreleased)
   - Accept COPYING,COPYING.lesser, and licence as license file (Zeger-Jan van de Weg)
   - Fix emoji aliases problem
   - Fix award-emojis Flash alert's width
+  - Emoji picker improvements
 
 v 8.2.3
   - Fix application settings cache not expiring after changes (Stan Hu)

app/assets/stylesheets/pages/issuable.scss

@@ -129,10 +129,18 @@
     border-color: $border-color;
     cursor: pointer;
 
+    &:hover {
+      background-color: #dce0e5;
+    }
+
     &.active {
       border-color: $border-gray-light;
       background-color: $gray-light;
 
+      &:hover {
+        background-color: #dce0e5;
+      }
+
       .counter {
         font-weight: bold;
       }
@@ -170,7 +178,18 @@
 
       > li {
         cursor: pointer;
-        margin: 5px;
+        width: 30px;
+        height: 30px;
+        text-align: center;
+        @include border-radius(5px);
+
+        img {
+          margin-bottom: 2px;
+        }
+
+        &:hover {
+          background-color: #ccc;
+        }
       }
     }
   }