Use srcset on Themen Images

templates/themen/index.twig

@@ -11,8 +11,14 @@
             </a>
         </h3>
         <div class="wm-card__media ">
-            <img class="wm-image   wm-card__image" loading="lazy" src="{{ craft.app.sites.primarySite.baseUrl}}/{{image.url}}" width="350"
-                height="197" data-src="" alt="Bildbeschreibung">
+            {% do image.setTransform({ height: 300 }) %}
+            {{ tag('img', {
+            src: image.url,
+            width: image.width,
+            height: image.height,
+            srcset: image.getSrcset(['1.5x', '2x', '3x']),
+            alt: image.title,
+            }) }}
         </div>
         <div class="wm-card__content wm-rich-text ">
             {{ newsElement.teaser }}