overflox slide programme

web/themes/custom/colloque2024/css/components/thumbnails/thumbnails.scss

@@ -3,6 +3,7 @@ section {
   article.thumbnails.programme {
     border: 1px solid $lightgrey;
     width: calc(100% / 4 - 0.5rem * 2);
+    overflow: hidden;
     &:hover{
       border: none;
       @include shadow;