The HTML Inline CSS Cheat Sheet provides easy guidance for designing a stage or bucket in ONevents. There's also a global CSS, but you can also integrate CSS directly into the HTML file.
<div style="color: blue; font-size: 18px;">A div container</div>
<p style="font-weight: bold;">A fat paragraph</p>
<span style="background-color: yellow;">A yellow chip element</span>
<img src="bild.jpg"alt="Beschreibung des Bildes"style="width: 300px; border: 1px solid
black;">
<a href="https://www.example.com"style="text-decoration: none; color: green;">A
green link to Example.com</a>
- List item 1
- List item 2
</ul
There are, of course, many more HTML and CSS tags – these can easily be found on the Internet. e.g. HERE