A responsive email design is all about coding HTML emails in a way that adjusts the email layout to different viewport or screen sizes. This enables the layout to render appropriately across devices of all sizes, such as laptops, tablets, and smartphones.
CSS (cascading style sheets) plays a big role in responsive emails. Responsiveness relies on a particular CSS element, media queries, which define the minimum and maximum widths for each specific email layout. As the viewport size changes, the email layout shifts to accommodate the smaller or larger viewing area. Mobile-friendly email designs are especially important, as they allow recipients to open emails on a mobile device without interruption.