Outlook Email Template Generator produces markup written for the client that breaks everything else. Outlook on Windows renders HTML through the Microsoft Word layout engine rather than a browser engine, which means flexbox, grid, most positioning, background images on many elements and media queries are ignored or handled unpredictably. The export here avoids all of that by construction. Layout is a full width background table holding a 600 pixel content table, which is the one structure Word based rendering handles reliably, and 600 pixels fits the Outlook reading pane without clipping. The body is a single column, so nothing needs a media query to reflow on a phone, which is exactly the fallback Outlook forces on you anyway. Padding lives on table cells rather than on inline elements, because Word based rendering ignores padding on spans and anchors. Every style is inline, which also serves Outlook Web and the mobile apps, since they strip head styles. For a simple text email that arrives intact in Outlook, Gmail and Apple Mail alike, this is enough. If you later add a coloured button, build it as a table cell with a background colour rather than a styled link, and test it in a real Outlook client before sending at volume.
Email HTML development is uniquely challenging because email clients use widely different rendering engines with varying levels of CSS and HTML support. Microsoft Outlook (still the dominant email client in enterprise environments) renders HTML using Microsoft Word's layout engine, which supports only a fraction of modern CSS. This means CSS flexbox, grid, and many positioning properties simply do not work in Outlook, requiring table-based fallbacks that web developers stopped using in the early 2000s. The Email Template Builder writes those table-based fallbacks for you: a full-width background table holding a single 600 pixel content table, with every style declared inline on the element rather than in a stylesheet. Responsive email design (adapting layout for mobile versus desktop) usually requires media queries, which most modern email clients support but Outlook does not. The builder avoids that dependency instead of working around it, by keeping the body to a single column at a width that already fits a phone screen, so there is nothing that needs to reflow and the layout reads correctly even in clients with no media query support at all. Beyond technical compatibility, email template design has well-established best practices. A single-column layout performs better on mobile than multi-column layouts. A clear call-to-action button with high color contrast outperforms text links for click-through rates. Images should include descriptive alt text because many email clients block images by default, and a significant portion of recipients will read the email with images disabled. Pre-header text (the preview text visible in inbox list views) should be crafted to complement the subject line and increase open rates.