Ticket #23584: 23584.5.diff

wp-content/themes/twentythirteen/style.css

@@ -738 +738 @@
 }
 
 .wp-caption .wp-caption-text,
-.entry-caption {
+.entry-caption,
+.gallery-caption {
         color: #220e10;
         font-size: 18px;
         font-style: italic;
@@ -1244 +1245 @@
 .gallery-item {
         float: left;
         margin: 0 4px 4px 0;
+        overflow: hidden;
+        position: relative;
 }
 
 .single .gallery-columns-1.gallery-size-medium,
@@ -1328 +1331 @@
 }
 
 .gallery-caption {
-        color: #777;
-        font-size: 14px;
-        font-style: italic;
-        padding-top: 4px;
+        background-color: rgba(255, 255, 255, 0.8);
+        height: 50%;
+        line-height: 1.2;
+        margin: 0;
+        overflow: hidden;
+        padding: 2px 10px;
+        position: absolute;
+        bottom: -50%;
+        text-align: left;
+        -webkit-transition: bottom 400ms ease;
+        transition:         bottom 400ms ease;
+        width: 100%;
 }
 
-.gallery-caption {
-        width: 90%;
+.gallery-item:hover .gallery-caption {
+        bottom: 0;
 }