How to Add Custom Block Styles to WordPress Gutenberg Blocks
This post explains how to set up block styles for blocks in Gutenberg, with either PHP or Javascript - and touches upon ideas to solve stylesheets.
WordPress Theme Tutorial for Beginners – Part 6: A Theme’s Functions.php
In this lesson we'll learn about and how to add the WordPress theme's functions.php file and how to add a theme's stylesheets and scripts the proper way.
All about Adding Styles and Scripts in WordPress
This post goes into detail with code examples of how to add scripts and styles to WordPress the correct way, both files and outputting variables.