Safe Class Names
Replace escaped characters in class names and CSS selectors
Introduction
This plugin replaces escaped characters in class names from your <style> tags and inside class="" attributes with safe characters, that do not need CSS escaping.
For example, it replaces:
\:and\/with-\%withpc\.with_
See the full list of replacements.
But... why?
So you can use those cool Tailwind CSS selectors in HTML emails.
Escaped characters in CSS selectors or HTML class names are not supported by all email clients (currently Gmail being the biggest one), so you can use this plugin to replace them with safe alternatives.
Install
$ npm i posthtml posthtml-safe-class-names
Usage
Consider example.html:
<!DOCTYPE html>
<html>
<head>
<style>
.w-3\/5 {
width: 60%;
}
/* JIT arbitrary values are also supported */
.bg-\[\#1da1f1\] {
background-color: #1da1f1;
}
@media (max-width: 600px) {
.sm\:w-1\/2 {
width: 50%;
}
}
</style>
</head>
<body>
<div class="w-3/5 sm:w-1/2 bg-[#1da1f1]">Lorem ipsum</div>
</body>
</html>import {readFileSync, writeFileSync} from 'node:fs'
import posthtml from 'posthtml'
import safeClassNames from 'posthtml-safe-class-names'
const html = readFileSync('./example.html')
posthtml([
safeClassNames()
])
.process(html)
.then(result => writeFileSync('./after.html', result.html))Result:
<!DOCTYPE html>
<html>
<head>
<style>
.sm-w-3-5 {
width: 60%;
}
.bg-_1da1f1 {
background-color: #1da1f1;
}
@media (max-width: 600px) {
.sm-w-1-2 {
width: 50%;
}
}
</style>
</head>
<body>
<div class="w-3-5 sm-w-1-2 bg-_1da1f1">Lorem ipsum</div>
</body>
</html>Options
replacements
The plugin accepts an options object where you can define character replacement mappings:
{
':': '-',
'\/': '-',
'%': 'pc',
'.': '_',
// ...
}See the full list of replacements.
Besides adding new mappings, you can of course override the default ones.
Using the same example.html, let's choose to replace \: in our class names with __ instead of -:
posthtml([
safeClassNames({
replacements: {
':': '__',
}
})
])
.process(html)
.then(result => writeFileSync('./after.html', result.html))Result:
<!DOCTYPE html>
<html>
<head>
<style>
.sm__w-3-5 {
width: 60%;
}
.bg-_1da1f1 {
background-color: #1da1f1;
}
@media (max-width: 600px) {
.sm__w-1-2 {
width: 50%;
}
}
</style>
</head>
<body>
<div class="w-3-5 sm__w-1-2 bg-_1da1f1">Lorem ipsum</div>
</body>
</html>
