diff --git a/website/common/templates/common/blocks/image-caption.html b/website/common/templates/common/blocks/image-caption.html
index 9baff07..610a0b7 100644
--- a/website/common/templates/common/blocks/image-caption.html
+++ b/website/common/templates/common/blocks/image-caption.html
@@ -2,7 +2,7 @@
 
 <figure>
   <div class="image">
-    <a href="{% image_url value.image 'original' %}" class="glightbox" data-gallery="content" data-height="70vh" data-alt="{{ value.caption|richtext|extract_text }}">
+    <a href="{% image_url value.image 'original' %}" class="glightbox" data-gallery="content" data-height="70vh" data-width="95vw" data-alt="{{ value.caption|richtext|extract_text }}">
       <img src="{% image_url value.image 'width-1500' %}" alt="{{ value.caption|richtext|extract_text }}" loading="lazy" decoding="async" />
     </a>
   </div>
diff --git a/website/contrib/mermaid_block/templates/contrib/blocks/mermaid.html b/website/contrib/mermaid_block/templates/contrib/blocks/mermaid.html
index 3f6a58f..0a0dbb4 100644
--- a/website/contrib/mermaid_block/templates/contrib/blocks/mermaid.html
+++ b/website/contrib/mermaid_block/templates/contrib/blocks/mermaid.html
@@ -2,7 +2,7 @@
 
 <figure>
   <div class="image">
-    <a href="https://mermaid.ink/svg/{{ value.pako }}" data-gallery="content" class="glightbox" data-type="image" data-height="60vh" data-alt="{{ value.caption|richtext|extract_text }}">
+    <a href="https://mermaid.ink/svg/{{ value.pako }}" data-gallery="content" class="glightbox" data-type="image" data-height="60vh" data-width="95vw" data-alt="{{ value.caption|richtext|extract_text }}">
       <img src="https://mermaid.ink/svg/{{ value.pako }}" referrerpolicy="no-referrer" alt="{{ value.caption|richtext|extract_text }}" loading="lazy" decoding="async" />
     </a>
   </div>