support images

index.js

@@ -0,0 +1,12 @@
+// Set the ratio variable on each image.
+document.querySelectorAll("img").forEach(img => {
+  function onLoaded() {
+    const ratio = img.naturalWidth / img.naturalHeight;
+    img.style.setProperty("--ratio", ratio);
+  }
+  if (img.loaded) {
+    onLoaded();
+  } else {
+    img.addEventListener("load", onLoaded);
+  }
+});