by philbuchanan on WordPress.org

Accordion block settings sidebar
Accordion Blocks is a simple plugin that adds a Gutenberg block for adding accordion drop-downs to your pages.
The accordions should blend seamlessly with your theme. However, you may want to add custom styles to your theme.
wp.blocks.registerBlockStyle.The plugin will ultimately output following HTML (simplified for this example):
Title with H2 tag
Content
You can use the following CSS classes to customize the look of the accordion.
.c-accordion__item {} /* The accordion item container */
.c-accordion__item.is-open {} /* is-open is added to open accordion items */
.c-accordion__item.is-read {} /* is-read is added to accordion items that have been opened at least once */
.c-accordion__title {} /* An accordion item title */
.c-accordion__title--button {} /* An accordion item title that is using a `