diff --git a/docs/assets/css/bootstrap.css b/docs/assets/css/bootstrap.css
index 7d706b036e..c315667517 100644
--- a/docs/assets/css/bootstrap.css
+++ b/docs/assets/css/bootstrap.css
@@ -5059,6 +5059,10 @@ input[type="submit"].btn.btn-mini {
   -webkit-box-shadow: 0 1px 3px rgba(0, 0, 0, 0.055);
      -moz-box-shadow: 0 1px 3px rgba(0, 0, 0, 0.055);
           box-shadow: 0 1px 3px rgba(0, 0, 0, 0.055);
+  -webkit-transition: all 0.2s linear;
+     -moz-transition: all 0.2s linear;
+       -o-transition: all 0.2s linear;
+          transition: all 0.2s linear;
 }
 
 a.thumbnail:hover {
diff --git a/less/thumbnails.less b/less/thumbnails.less
index 99b09dd86b..280266ff90 100644
--- a/less/thumbnails.less
+++ b/less/thumbnails.less
@@ -31,6 +31,7 @@
   border: 1px solid #ddd;
   .border-radius(4px);
   .box-shadow(0 1px 3px rgba(0,0,0,.055));
+  .transition(all .2s linear);
 }
 // Add a hover state for linked versions only
 a.thumbnail:hover {