Shroom Space Theme

A cosmic dark theme for VS Code with 7 variants, including accessibility-focused CVD adaptations. 1049 colour tokens covering the current VS Code API, 32 semantic token rules, WCAG 2.1 AA, and 9-format multi-editor export.

Themes

The CVD variants render the theme as it would appear to a dichromat, the most severely affected case. Dichromats are roughly a quarter of people with colour vision deficiency; the other three quarters are anomalous trichromats, whose impairment is milder. So these variants are a conservative worst-case collision detector rather than a picture of what any individual sees. Full caveats, including what is explicitly not guaranteed, are in docs/color-science.md.

On dark mode and eye strain

Dark-on-light text does read measurably faster in some conditions. The size of the effect, and the fact that it is a luminance effect rather than a polarity effect, are worth stating plainly rather than leaving as folklore:

• Follow-up work that equated display luminance between polarities found the proofreading advantage of light mode disappeared (η² < 0.01) while display luminance kept its effect (η² = 0.12). The mechanism is pupil size: positive polarity gives 2.09 mm against 3.65 mm, d = 2.96.
• In bright ambient light the penalty is not detectable at all (p = 0.665). It concentrates in evening and dim-room use.
• It grows as text gets smaller.

The background is not pure black. #24212E sits inside APCA's black soft-clamp regime, which exists because WCAG 2.x overstates contrast for near-blacks. Perceptually, pure black is not achievable anyway: the eye perceives black as about 0.0044 cd/m² even in a dim room. If you want the last few percent of reading speed, the light theme is there, and the accurate reason is above.

Features

• Accent color customization -- 7 presets (purple, teal, green, amber, rose, sky, coral) + custom HSL via settings
• Auto dark/light switching -- follows OS appearance automatically
• Semantic token support -- 32 rules covering all VS Code standard types and modifiers
• 9 export formats -- tmTheme, JetBrains (.icls), Vim, Windows Terminal, iTerm2, Warp, Alacritty, Kitty, CSS
• Tailwind CSS plugin -- tools/tailwind-plugin.js for use in Tailwind projects
• WCAG 2.1 AA -- enforced in CI on the alpha-composited pair, so translucent tokens are measured as rendered rather than as authored
• Perceptual separation -- token colours are kept apart by APCA |Lc| so no two competing categories differ by hue alone. See docs/color-science.md
• Colour vision deficiency variants -- simulated in linear RGB using Machado 2009 and Brettel 1997. These are worst-case collision detectors, not depictions of any user's experience
• i18n docs -- English, Simplified Chinese, Japanese

Installation

VS Code Marketplace

code --install-extension wyattau.shroom-space-theme

Or search "Shroom Space" in the Extensions panel.

Manual

Download the .vsix from releases:

code --install-extension shroom-space-theme-*.vsix

Accessibility

Contrast and colour separation are measured, not judged by eye, and enforced in CI. What that does and does not cover, how the CVD variants should be interpreted, and what to test with real users is in ACCESSIBILITY.md and docs/color-science.md.

Short version: the CVD variants are a worst-case collision detector, not a depiction of what anyone sees. A pair that is distinguishable in them is distinguishable for the milder anomalous trichromacies that make up most colour vision deficiency.

Variables are pink rather than the more conventional blue for this reason: a blue variable sat 1.55 CIEDE2000 from the purple keyword under deuteranopia, which is functionally the same colour. The full measurement is in the documentation.

Accent Color

Use the command palette (Ctrl+Shift+P / Cmd+Shift+P) and search Shroom: Set Accent Color. Or configure in settings:

{
  "shroom-space.accentColor": "purple",     // purple | teal | green | amber | rose | sky | coral | custom
  "shroom-space.autoSwitch": true,          // auto dark/light on OS change
  "shroom-space.customAccentHsl": "280,70,80"  // only when accentColor is "custom"
}

Preview

WASM Previewer (Rust/Leptos, 128KB): wyattau.github.io/shroom-theme/previewer

Static preview with all 7 variants: wyattau.github.io/shroom-theme

WCAG contrast report: wyattau.github.io/shroom-theme/wcag.html

Color Palette

Token colours are kept apart by APCA lightness contrast, not by hue alone. Every adjacent pair differs by at least 2 |Lc|, which is finer than one step of APCA's own lookup tables, so no two categories collapse when hue is hard to discriminate. The muted comment colour is deliberately lower: it is de-emphasis, held to the 3:1 that WCAG sets for non-text components rather than to 4.5:1.

Development

Prerequisites

• Node.js >= 24
• npm >= 10

Commands

Recommended Icon Theme

Catppuccin Icons (Mocha flavor) pairs naturally -- its palette (mauve #cba6f7, teal #94e2d5, blue #89b4fa) is within 10-15 hex of Shroom Space's accents. No configuration needed.

For pixel-perfect control, Material Icon Theme with:

{ "material-icon-theme.folders.color": "#BE9AF7", "material-icon-theme.files.color": "#CCC8D9", "material-icon-theme.saturation": 0.75 }

Neovim

-- lazy.nvim
{ "wyattau/shroom-theme", name = "shroom-theme", lazy = false, priority = 1000, config = function() vim.cmd.colorscheme("shroom-space") end }

Or copy editors/neovim/colors/*.lua to ~/.config/nvim/colors/ and :colorscheme shroom-space.

7 variants: shroom-space, shroom-space-light, shroom-space-deuteranopia, shroom-space-protanopia, shroom-space-tritanopia, shroom-space-monochrome, shroom-space-high-contrast.

Helix

Copy editors/helix/shroom_space.toml to ~/.config/helix/themes/ and set in config.toml:

theme = "shroom_space"

7 variants available as shroom_space, shroom_space_light, shroom_space_deuteranopia, etc.

License

Apache License 2.0. See LICENSE.

Links

• Repository
• Issues
• Changelog
• Roadmap