Your emails can look different to your subscribers for many reasons including:
- Each email client renders emails slightly differently
- Users may have unique settings enabled on their devices (such as dark mode) that changes how your email designs look
- Certain fonts are accepted by some email clients but not others
Limiting the number of elements in your template (such as images, colors, etc.) can help your emails have the highest chance for consistency across different devices and email clients.
Check out these resources for more details + tips on designing your emails/templates: