I’ll introduce npm Juice, which converts CSS within style tags to inline styles, making it convenient for creating HTML emails.

Converting CSS to Inline Styles with npm Juice

• GitHub: Automattic/juice: Juice inlines CSS stylesheets into your HTML source.

When you execute the following JavaScript code:

var juice = require('juice');
var result = juice("
");

The result contains HTML converted to inline styles like this:

Incidentally, while Gmail previously didn’t support style tags, they have been supported since October 2016.

• Official developer page: CSS Support | Gmail & Inbox Sender Resources | Google Developers
• List of CSS properties and media queries supported by Gmail: Gmail Supported CSS Properties & Media Queries | Gmail & Inbox Sender Resources | Google Developers

CSS → Inline Style Conversion Site

There’s also an online site that converts style tags to inline styles.

• Juice CSS Inliner Online

That’s all from the Gemba where I wanted to convert style tags to inline CSS for HTML email creation.