Crafting css styling for a specific topic?

If you need to add styles to posts, you can wrap the post content in a div that has a data attribute. The data attribute will not be stripped from div tags. For example, if you create a post with the following HTML:

<div data-custom>
This is in a custom div
</div>

<div data-custom=true>
This is a custom div with the attribute set to true
</div>

you can target the divs with the following CSS:

[data-custom] {
    color: blue;
}

[data-custom=true] {
    background: red;
}