The inspiration behind placing the design of placing a post in a bounding box came from reading an architectural magazine at the Nieuwe Instituut's library in Rotterdam.
(Sidenote: They have an amazing library with architectural/urban design and planning themed books, and even let you take some of them home for free! I took a couple along with me the last time I was there. Might write about some interesting findings and/or inspiration from those specific books, plus my visit to the museum some other time.)

I was already mulling over some ideas in my ahead about the base design I wanted my posts to have (more site details outlined here). I wanted to be heavily text-focussed, and easily re-usable. The design I saw above jumped out because I liked the way it had separate demarcations for the different metadata sections, which matched the different fields I include in the frontmatter of each post. Things like the description, date, and tags, and also lets you add more lines for any other fields in the future. It was also simple and I liked the compact look of it.
Example of the frontmatter used in this post to generate the metadata:
---
title: How the bounding box design came to be
description: Documenting the design and technical decisions behind the site. This one's about the bounding box design
date: 2025-08-02
tags: ['meta', 'tech', 'site', 'how its made', 'projects']
layout: layouts/bounding_box.njk
---
It seems like a nice exercise to read more magazines/self-publishings to hunt for fun page layouts and use them for some one-off post layout.