IntelliJ Plugin: WCAG AAA Contrast Editor Themes — 4 Themes for Long Reading Sessions, Glare-Lit Offices and Colour-Blind Vision

Four editor themes for IntelliJ IDEA-based IDEs, built contrast-first instead of colour-first. Each theme carries the same 15 named palette keys (bg, bg_alt, fg, muted, border, selection, accent, keyword, string, number, func, type, green, blue, red) — 60 colour values in the pack. What was measured, not asserted: • All 11 text colours in all 4 themes were computed against their own background using the WCAG 2.1 relative-luminance formula. Lowest ratio in the whole pack: 7.18:1. W3C WCAG 2.1 SC 1.4.6 (AAA, normal text) requires 7:1; SC 1.4.3 (AA) requires 4.5:1. • Comments (`muted`) are held to the same AAA floor as body text. That is the one colour most palettes let drift, and it is the one you read most while reviewing someone else's code. • Selected text stays legible: every text colour measures at least 4.75:1 against that theme's selection band — above the 4.5:1 AA floor. The selection band itself sits at 1.50:1 against the background, visible without washing the text out. • Editor and UI borders measure at least 3.03:1 against the background — SC 1.4.11 (non-text contrast) requires 3:1. • Keyword, string, number, function, type and comment are mutually separated by at least 20.3 ΔE (CIE76) in every theme, so the six roles do not collapse into one another at small font sizes. The four variants (one axis is your room, the other is your eyes): 1. AAA — Dark Room. Cool near-black base for a dim room. 2. AAA — Bright Office. Pure-white base for glare and daylight, where dark themes lose their contrast advantage. 3. AAA — Night Warm. Warm dark base with the blue-heavy hues pulled out of the syntax roles for late sessions. 4. AAA — Colour-Blind Safe. Syntax roles re-coded onto the blue↔yellow axis plus lightness tiers. Under simulated deuteranopia (Machado et al. 2009 transform, severity 1.0) the six syntax roles stay at least 12.6 ΔE apart, and the error/success pair (red/green) stays 24.7 ΔE apart; under simulated protanopia the six stay at least 7.8 ΔE apart. The other three themes are not colour-blind-tuned — this is the one that is. All 60 hex values are published in the listing as a plain table, so the same measured palette can be carried into your terminal, diff viewer or docs theme.

def greet(name):
    # say hello
    return f"hi {name}"

def greet(name):
    # say hello
    return f"hi {name}"

def greet(name):
    # say hello
    return f"hi {name}"

def greet(name):
    # say hello
    return f"hi {name}"