Recommended sizes — Modal / Newsletter image: 960×480px (2:1), PNG/JPG/SVG, under ~500 KB · PDFs & videos (MP4/WebM): up to 200 MB. Images are shown up to 480px wide and cropped to a 240px-tall band, so keep key content centered. Videos play inline with controls (add an image as the poster frame). Banners and notifications are text-only.