Opendian

Opendian

A developer-documentation theme for Obsidian. Monospace typography, a layered radius system, and minimal chrome — inspired by the OpenCode visual language. Makes your vault feel like a professional code editor, not a note-taking app.

中文介绍 · Light & Dark · Desktop & Mobile · No plugin required

Recommended Font

Opendian is designed around IBM Plex Mono, the same open-source mono family used by OpenCode's documentation. The theme includes a fallback stack, but installing IBM Plex Mono gives the sidebar, headings, and editor text the intended spacing.

macOS users with Homebrew can install it with:

brew install --cask font-ibm-plex-mono

You can also download it from the official IBM Plex repository. Restart Obsidian after installing the font.

Why Opendian

• Monospace-first typography — IBM Plex Mono → Berkeley Mono → JetBrains Mono across headings, body, and UI. Your vault reads like terminal output and technical documentation.
• Layered radius system — content stays sharp (0px for code blocks, tables, callouts), controls are soft (4–8px for buttons, inputs, tabs), modals are softer (12px). One coherent principle instead of random roundness.
• Minimal-lines chrome — hard 1px borders are replaced by background-step separation. The tab bar, titlebar, and view header blend into one immersive surface.
• OpenCode color system — precise tokens derived from the OpenCode website and desktop client. Monochrome links and primary actions, with blue reserved for selection and semantic accents.
• Flat active tab — inactive tabs are plain text with hairline dividers; the active tab is a quiet tinted chip that stays aligned with the native side docks.
• Terminal-grade code blocks — softly-filled surface with language labels. No fake macOS window dots, no copy-button chrome, no drop shadows.
• Semantic callouts — a low-tint technical surface with a slim semantic rail and colored title/icon, keeping the page calmer than traditional Obsidian callout blocks.
• IDE-style sidebar — black accent bar on the active file, auto-collapsing top toolbar (Folio-style), and a dual-tone vault wordmark.

Design

Opendian is built on the OpenCode color system — a precise, monochrome-forward palette with a single blue accent:

Light mode (Docs Style):

Dark mode (Terminal Style):

Typography uses a monospace-first stack with CJK fallbacks:

• Headings and body: IBM Plex Mono, Berkeley Mono, JetBrains Mono, SF Mono → Source Han Sans SC
• Interface: Same mono stack → PingFang SC
• Code: Same mono stack (no fallback needed)

Radius Scale

What Opendian Styles

Opendian covers every surface that shapes the developer writing experience:

• Code blocks — softly-filled surface with language-label header; no decorative dots, copy-button chrome, or shadows
• Inline code — borderless neutral tint + monochrome text
• Callouts — slim semantic rail + low-tint surface, with color concentrated on title/icon
• Tables — minimalist 1px horizontal hairline rows, zero radius, compact density
• Blockquotes — double neutral rail, no accent color bleed
• Headings — monospace, no decorative underlines, edit-reading size parity
• Tabs — immersive bar with a flat active chip, hairline dividers, and a geometric pinned-tab marker
• Sidebar — black accent bar on active file, auto-collapsing top toolbar
• Vault wordmark — dual-tone text treatment without a hard-coded avatar box
• Buttons — solid black/white primary CTA, outline secondary, 6px radius
• Toggles — rounded rectangle (5px track, 3px knob), not a pill
• Checkboxes — monochrome custom task states, no strikethrough on done tasks (fade only)
• Dropdowns — borderless with field-sizing: content for value-width sizing

Supported Checkbox States

Opendian supports Obsidian's native task syntax plus the common Minimal-style extended markers, redrawn as a black/white/gray icon set. No plugin is required; use ASCII brackets:

- [ ] todo
- [/] incomplete
- [x] done
- [X] done
- [-] canceled
- [>] forwarded
- [<] scheduled
- [?] question
- [!] important
- ["] quote
- [“] quote
- [*] star
- [i] info
- [I] idea
- [b] bookmark
- [l] location
- [S] savings
- [p] pros
- [c] cons
- [f] fire
- [k] key
- [u] up
- [d] down
- [w] win

Installation

Install from the Obsidian community theme browser:

1. Open Settings → Appearance → Themes → Manage
2. Search for Opendian
3. Install and enable the theme

Manual installation is also possible by downloading the latest release and placing theme.css and manifest.json in:

<vault>/.obsidian/themes/Opendian/

Compatibility

• Obsidian 1.4.0+
• Light and dark modes
• Desktop and mobile
• No plugin required

License

MIT