Definition
A VML conditional uses Vector Markup Language inside an Outlook conditional to render backgrounds and shapes Outlook's Word engine ignores in CSS.
Pair it with a CSS fallback for modern clients.
VML conditionals are how Outlook renders backgrounds reliably, using the vector format its Word engine understands. A CSS fallback covers modern clients. Testing in Outlook prevents broken images from small syntax errors.
Using VML
Use VML for bulletproof full-bleed backgrounds in Outlook.
Keep a CSS background fallback for modern clients.
Why It Matters
VML conditionals are how Outlook renders backgrounds reliably. Understanding them is essential for full-bleed Outlook design.
Best Practices
- Use VML for bulletproof full-bleed backgrounds in Outlook.
- Keep a CSS background fallback for modern clients.
- Test VML in Outlook because small errors render as broken images.
- Keep VML code tidy and documented.
- Align Outlook and modern versions.
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Frequently Asked Questions
Outlook ignores CSS backgrounds on many elements; VML paints them for Outlook. VML conditionals are how Outlook renders backgrounds reliably, using the vector format its Word engine understands.
Yes, for Outlook desktop compatibility. A CSS fallback covers modern clients.
Yes, provide both and let conditionals pick. Testing in Outlook prevents broken images from small syntax errors.
Small syntax errors render as broken images. VML conditionals are how Outlook renders backgrounds reliably, using the vector format its Word engine understands.
No, it is Outlook-specific. A CSS fallback covers modern clients.