SimplyCast uses its own Cascading Style Sheets (CSS) when an email is compiled before sending. This is because we merge in a link for people to unsubscribe, as well as additional footer information.
If you add your own CSS code in your HTML, such code could conflict with the CSS code used by our template system and is not recommended. If you are using your own HTML code, make sure that styles defined in <style> tags are not included with the rest of the HTML source. If you are not sure if you have CSS code in your HTML source code, we recommend copying only the content between the two <body> </body> tags for best compatibility.
CSS that is written inline would be fine, as these styles are defined within the body tags (<body> </body>) of the HTML code.