Inline styles should take precedence of internal or external declarations.
Inline:
Code:
<span style="color: black; font-weight: bold; font-size: 1em">Text effected</span>
Internal:
Code:
<style type="text/css">
p {
color: black;
font-weight: bold;
}
</style>
<p> This should be styled in websites, but email providers will likely strip it out for security and styling reasons. </p>
External (doesnt work for emails):
Code:
<link rel="stylesheet" type="text/css" href="mystyle.css" />