What is External CSS in Email Marketing?
External CSS refers to the practice of linking a separate CSS file to your HTML email to style its content. This method is commonly used in
web development, where a single stylesheet can be applied across multiple web pages. In the context of email marketing, however, its usage is more complicated due to various email client limitations.
Challenges with External CSS in Email Marketing
One of the primary challenges is that many email clients, including popular ones like Gmail and Outlook, do not fully support external CSS files. This lack of support can lead to your email appearing differently across various
email clients, undermining the consistency of your branding and user experience.
Are There Any Workarounds?
Yes, there are a few workarounds. One common method is to use
inline CSS, where styles are applied directly to the HTML elements within the email. Although this can be more tedious and result in bulkier HTML code, it ensures greater compatibility across different email clients. Alternatively, you can use tools like
CSS inliner services that automatically convert your external CSS into inline styles.
Best Practices for Using External CSS
If you decide to use external CSS despite its limitations, there are some best practices to follow: Test extensively across different email clients and devices to ensure compatibility.
Use
fallback styles to handle cases where the external CSS file might not be loaded.
Keep your CSS
minimal and efficient to reduce potential issues.
Use media queries carefully, as support varies across email clients.
Conclusion
While using external CSS in email marketing can offer benefits in terms of code organization and efficiency, it comes with significant challenges due to varying levels of support across different email clients. Understanding these limitations and employing best practices can help you make an informed decision on whether to use external CSS in your email marketing campaigns.