twine-css-template VS harlowe-audio

Second, I would recommend grabbing this stylesheet and copy-pasting it into the stylesheet section of your twine story. It's quite nicely annotated with comments throughout that will help you figure out what you can do in terms of CSS styling.

Harlowe can be a pain in the ass to do CSS for since it's pretty opaque about it. I'd suggest grabbing this template stylesheet and dropping it into your game, then messin' about with the values.

https://twinelab.net/harlowe-audio/#/v2?id=configuration

Following all the instructions given on the Official HAL Guide I was able to get it working with Absolute URLS. They are placed inside an isolated passage titled "hal.tracks" and work fine. However, for compatibility's sake, I want to use Relative URLS. So currently my sound effects look like this:

You may want to try copying in the code again, since unless the code you're copying from has an issue (and do make sure it's the latest release from the source), that errors suggests you're missing something causing the brackets not to close. The guide might be of help, if you haven't already followed it.

Harlowe 3.2.1 Harlowe Audio Library (twinelab.net) and Configuration (twinelab.net).

This chunk of the HAL documentationhas some excellent examples of snippets showing pause and play commands for a given track using Harlowe macros. I hope this helps!

The Installing HAL in Twine 2 section of the above linked documentation site explains how to add the required JavaScript to the Story JavaScript area of a Twine 2.x application project. It also explains how to add the required CSS to your project's Story Stylesheet area.