oxiui-theme — COOLJAPAN dark/light themes for OxiUI

oxiui-theme supplies the visual identity of the COOLJAPAN OxiUI toolkit: a dark/light Tokyo Night palette plus the full design-system scaffolding around it — design tokens (spacing / radius / elevation), a typographic scale, a CSS-subset stylesheet engine with selector matching and specificity, animation tokens, responsive breakpoints, semantic-palette derivation, a runtime theme manager with change listeners, high-contrast accessibility variants, and a gallery of popular ready-made palettes (Nord, Dracula, Solarized, Catppuccin, Material).

Everything is expressed in terms of oxiui-core's Theme, Palette, Color, and FontSpec types, so any adapter that consumes a &dyn Theme works with these themes unchanged. The crate is #![forbid(unsafe_code)] and 100% Pure Rust — its only dependency is oxiui-core.

Installation

[dependencies]
oxiui-theme = "0.1.0"

Quick Start

use oxiui_core::Theme;
use oxiui_theme::{cooljapan_default, ThemeExt};

// The default COOLJAPAN theme is Tokyo Night (dark).
let theme = cooljapan_default();
assert_eq!(theme.palette().background.0, 26); // #1A1B26

// ThemeExt augments any Theme with tokens, typography, and the
// extended semantic palette (blanket-implemented for every Theme).
let tokens = theme.tokens();
let scale = theme.typography();
let extended = theme.extended_palette();
let _ = (tokens, scale, extended);

Building a validated custom theme

use oxiui_core::Color;
use oxiui_theme::PaletteBuilder;

let result = PaletteBuilder::new()
    .background(Color(26, 27, 38, 255))
    .surface(Color(36, 40, 59, 255))
    .primary(Color(122, 162, 247, 255))
    .on_primary(Color(26, 27, 38, 255))
    .text_primary(Color(192, 202, 245, 255))
    .text_secondary(Color(86, 95, 137, 255))
    .build(); // -> Result<CooljapanTheme, Vec<ContrastWarning>>
let _ = result;

API Overview

Theme construction (crate root)

All three constructors return Box<dyn Theme>.

ThemeExt trait

Blanket-implemented for every oxiui_core::Theme, returning COOLJAPAN defaults; concrete themes may override.

OS accessibility helpers

os_prefers_high_contrast() and os_prefers_reduced_motion() read the OXIUI_HIGH_CONTRAST / OXIUI_REDUCED_MOTION environment variables ("1"/"true" = active).

tokens module — design tokens

DesignTokens — spacing(SpacingStep), radius(RadiusStep), elevation(level). SpacingStep and RadiusStep are stepped scales.

typography module

TypographyScale — roles_descending() yields six TextStyleTokens (heading → caption). TextStyleToken carries a per-role text style.

spec module — borders & shadows

stylesheet module — CSS-subset engine

compile module

CompiledStyleSheet — pre-compiled stylesheet for fast repeated styling; compile(sheet, generation), compute_style.

inheritance module

resolve(parent, child) (re-exported as resolve_inheritance) — propagate inherited CSS properties from a parent ComputedStyle into a child.

style_cache module

StyleCache — memoises computed styles; get_or_compute.

anim_tokens module — animation tokens

breakpoint module — responsive design

Breakpoint — responsive size tiers; for_width(width), min_width, matches_width.

manager module — runtime switching

ThemeManager — holds the active CooljapanTheme and notifies subscribers on change: new, theme, set_theme, subscribe, unsubscribe, listener_count. ThemeListener is the boxed callback type.

overlay module

PartialTheme + overlay(base, overrides) — layer partial overrides on top of a base Theme to produce a derived CooljapanTheme.

palette_ext module

ExtendedPalette — semantic palette derived from a base Palette; derive(base, dark) adds status/hover/etc. colours.

lazy_palette module

LazyPaletteVariants — lazily-computed interaction-state variants from a base colour: hover, pressed, disabled.

icons module

high_contrast module

cooljapan_high_contrast() / cooljapan_high_contrast_light() — accessible high-contrast palettes. Plus WCAG helpers wcag_luminance(r, g, b) and wcag_contrast(fg, bg).

builder module — validated palette builder

PaletteBuilder — fluent builder with WCAG contrast validation: background, surface, text_primary, text_secondary, primary, on_primary, validate() -> ValidationResult, build() -> Result<CooljapanTheme, Vec<ContrastWarning>>. Includes WcagLevel and ContrastWarning.

color module — colour utilities

Free functions over oxiui_core::Color: lerp, mix, lighten, darken, with_alpha, scale_alpha, to_hsl/from_hsl, saturate/desaturate, to_oklch/from_oklch, oklch_lerp, best_contrast.

gallery module — ready-made palettes

make_nord_dark, make_nord_light, make_dracula, make_solarized_dark, make_solarized_light, make_catppuccin_mocha, make_catppuccin_latte, make_material_dark, make_material_light — each returns a CooljapanTheme.

Tokyo Night palette (default dark)

Font: Inter, 14 pt, weight 400.

Related crates

• oxiui-core — defines Theme, Palette, Color, FontSpec (the only dependency)
• oxiui — the OxiUI facade
• oxiui-text — text layer whose FontSpec comes from a theme
• oxiui-accessibility — pairs with the high-contrast palettes here

License

Apache-2.0 — COOLJAPAN OU (Team Kitasan)