Codex theme - documentation layout with sidebar navigation and code blocks

For Documentation

Codex.

Ghost is a capable CMS, but Casper and Source are blog themes. Codex is purpose-built for technical documentation - 3-column layout with sidebar navigation, right-hand table of contents, breadcrumbs, code blocks with copy buttons, and custom membership pages. Everything a docs site needs, none of which exists in Ghost's default themes.

Ghost 5.x+

GScan 0 errors

14-day guarantee

Updated June 2026

$ 79

Compatible with Ghost 5.x+

Codex - Homepage (desktop)

Homepage - desktop

What's included.

LAYOUT

3-column layout: left sidebar navigation, main content, right-side table of contents

Collapsible sidebar navigation - tags as sections, posts as pages, active state highlighting

"On this page" table of contents with scroll-spy highlighting

Breadcrumbs on every doc page

Previous / Next post navigation at bottom of each page

Reading progress bar at top of page

CONTENT

Code blocks with syntax highlighting, language labels, and copy-to-clipboard

IBM Plex Sans body + IBM Plex Mono code typography stack

Callout cards: Tip, Warning, Important, Success variants

Toggle / accordion cards for FAQs

Dark mode toggle

~8KB JavaScript footprint

MEMBERSHIP

Custom sign-in page - full-page flow, not a Portal modal

Custom sign-up page with inline pricing tiers

Membership-aware navigation (logged-out / free / paid states)

Content gating with upgrade CTA

TECHNICAL

Homepage section grid with doc count badges per category

Components style guide (/components/)

GScan validated - 0 errors

routes.yaml included

Ghost 6.x compatible

Ghost 5.x / 6.x

Commercial license

Lifetime access

routes.yaml included

$ 79

14-day money-back guarantee. No questions.

Need more than a theme? The studio behind these takes custom builds. kontemi.com →