add base styles and scripts

web/app/themes/badegg/resources/scripts/lib/VideoSrcset.js

@@ -0,0 +1,24 @@
+export default function VideoSrcset( element )
+{
+  const sizes = JSON.parse(element.dataset.sizes);
+
+  Object.keys(sizes).forEach((key) => {
+    const size = key;
+    const source = element.querySelector('.bgvid-' + size);
+
+    if(source) {
+      const sourceWidth = source.dataset.width;
+      const poster = source.dataset.poster;
+
+      if(window.innerWidth >= sourceWidth) {
+        console.log('screen width is greater than or equal to the source width');
+        console.log('screen width: ' + window.innerWidth);
+        console.log('source width: ' + sourceWidth);
+
+        element.src = source.src;
+        element.poster = poster;
+        element.load;
+      }
+    }
+  });
+}