Using custom fonts can greatly enhance your email design. However, not all email clients support custom fonts. The best practice is to use web fonts with fallback options: @import url('https://fonts.googleapis.com/css2?family=Roboto:wght@400;700&display=swap');
body { font-family: 'Roboto', Arial, sans-serif; } In this example, the email will use the 'Roboto' font if supported, and fall back to Arial or a generic sans-serif font if not.