Webflow

Webflow is a visual website builder and content management system that lets designers produce production websites without writing code, while still generating standard HTML, CSS, and JavaScript. Founded in 2013, it is widely used by marketing teams and agencies for landing pages, campaign microsites, and full company sites.

Sites built on Webflow serve their images and other assets from Webflow's CDN, which uses the website-files.com domain. When those asset URLs appear in an email, they indicate that the brand's web presence — and often the landing pages a campaign points to — is built on Webflow.