Why is my custom template failing?

HTML

HTML errors are primarily caused by the use of smart quotes (also known as curly quotes). These are Unicode which often causes rendering issues. These are generally caused by auto-formatting when copying and pasting from a separate source.

Please note that you can use Unicode characters in the body of your email, but they cannot be included in any HTML tags.

To fix this error, convert all smart quotes to plain/straight quotes.

CSS

Media queries are the most common issue when using CSS for your template.

To resolve this, you will need to move each media query to its own style tag. An example of how one might format this is as follows: 

<style media="screen" type="text/css">
body {
    width: 75%;
}
</style>

<style media="only screen and (max-width: 650px)" type="text/css">
@media only screen and (max-width: 650px) {
    body {
    width: 80%;
    }
}
</style>

<style media="only screen and (max-width: 480px)" type="text/css">
@media only screen and (max-width: 480px) {
    body {
    width: 100%;
    }
}
</style>