center screenshots when they don't span the page width

media/css/mkt/slider.less

@@ -11,6 +11,7 @@
         white-space: nowrap;
         margin: 0;
         padding: 0;
+        text-align: center;
         -webkit-transition: .5s -webkit-transform ease-out;
         -moz-transition: .5s -moz-transform ease-out;
         &.panning {
@@ -21,7 +22,6 @@
     li {
         list-style-type: none;
         display: inline-block;
-        text-align: center;
         margin: 0;
         padding: 0;
         a {