diff --git a/templates/shortcodes/responsive_image.html b/templates/shortcodes/responsive_image.html
index 577e94b..7fc5879 100644
--- a/templates/shortcodes/responsive_image.html
+++ b/templates/shortcodes/responsive_image.html
@@ -11,7 +11,7 @@
     <img 
         src="{{img_400.url}}"
         srcset="{{img_400.url}} 400w, {{img_600.url}} 600w, {{img_800.url}} 800w"
-        sizes="(width <= 800px) 100vw, 800px"
+        sizes="(max-width: 800px) 100vw, 800px"
         alt="{{ alt }}"
         loading="lazy"
         decoding="async"