fix(a11y): make every text colour clear WCAG AA on every ramp

a11y.md flagged --yj-text-tertiary on --yj-bg-surface as 'borderline
(~4.1:1) but that needs a real measurement', and plan 007 parked it as
'worth measuring before planning'. Measured, against the rendered app
and then across all three background ramps: it failed AA in nine of
twelve text/surface combinations, as low as 2.31:1 on dark's overlay
and 2.55:1 on light's -- the app's most-used secondary text colour,
failing on every view. Not borderline. 110 failing nodes across twelve
views, now 0 of 659.

Three separate mechanisms, and only the first is the finding:

- The ramps. Tertiary is raised per ramp (#a6a6a6 dark, #949494 darker,
  #5c636a light), sized to the lightest surface it actually sits on and
  keeping its hue. Sizing it to bgOverlay too would need a grey lighter
  than secondary, so bgOverlay is documented as not a text surface and
  the one component that put text there uses primary.
- The avatar generator. hsl(hue, 45%, 35%) behind white initials failed
  for 35 of the 360 hues -- the yellow-green band -- so which artists
  were unreadable depended on how their names hashed. The two a sweep
  found were not the finding. 32% clears every hue.
- Jobs' local #ff6b6b, at 4.15:1 on elevated.

Pinned by a unit test over the palette table rather than a DOM sweep:
the ramps are pure data, and checking only what happens to be on screen
is exactly how the light ramp went unexamined. Note that make ui-visual
cannot see any of this -- the component tier renders the fallbacks,
because theme-store sets :root only in the real app.
This commit is contained in:
2026-08-13 00:33:50 -04:00
parent 31144e5dc7
commit 533c084f8a
14 changed files with 258 additions and 39 deletions
@@ -203,7 +203,11 @@ export class DownloadsView extends ViewLifecycleMixin(LitElement) {
border-radius: 6px;
font-size: 12px;
background: var(--yj-bg-overlay, rgba(255, 255, 255, 0.06));
color: var(--yj-text-secondary, #b3b3b3);
/* The only place in the app that puts text on bgOverlay,
which is too light on the dark ramp to carry anything
but primary: secondary measured 3.90:1 here. A notice
is the last thing that should be hard to read. */
color: var(--yj-text-primary, #fff);
}
.section-hint {
@@ -1,3 +1,4 @@
import { avatarBackground } from '@utils/avatar-color';
import { LitElement, html, css, nothing } from 'lit';
import { customElement, property, state } from 'lit/decorators.js';
import { designTokens } from '../../styles/tokens.css';
@@ -60,14 +61,6 @@ const NON_STUDIO_SECONDARY_TYPES = new Set([
/* ── Utility functions (duplicated from explore-view per design decision) ── */
function nameToHue(name: string): number {
let hash = 0;
for (let i = 0; i < name.length; i++) {
hash = name.charCodeAt(i) + ((hash << 5) - hash);
}
return Math.abs(hash) % 360;
}
function extractYear(dateStr: string): string {
if (!dateStr) return '';
return dateStr.substring(0, 4);
@@ -1884,7 +1877,6 @@ export class ExploreArtistDetails extends LitElement {
/* ── Render ── */
override render() {
const hue = nameToHue(this.artistName);
return html`
<div class="artist-header">
@@ -1898,7 +1890,7 @@ export class ExploreArtistDetails extends LitElement {
</button>
<div
class="artist-avatar"
style="background: hsl(${hue}, 45%, 35%)"
style="background: ${avatarBackground(this.artistName)}"
>
${this.artistImageURL
? html`<img
@@ -2392,7 +2384,6 @@ export class ExploreArtistDetails extends LitElement {
<h3 class="section-header">Similar Artists</h3>
<div class="similar-row ${collapsed ? 'collapsed' : ''}">
${visible.map((a) => {
const hue = nameToHue(a.name);
const imgURL = this.similarImageURLs.get(a.artistMbid);
return html`
<div
@@ -2412,7 +2403,7 @@ export class ExploreArtistDetails extends LitElement {
>
<div
class="similar-avatar"
style="background: hsl(${hue}, 45%, 35%)"
style="background: ${avatarBackground(a.name)}"
>
${imgURL
? html`<img
@@ -1,3 +1,4 @@
import { avatarBackground } from '@utils/avatar-color';
import { LitElement, html, css, nothing } from 'lit';
import { customElement, state, query as litQuery } from 'lit/decorators.js';
import '@components/page-header/page-header';
@@ -61,15 +62,6 @@ const MAX_SECTION_RESULTS = 10;
const THUMBNAIL_CACHE_LIMIT = 96;
/** Hash a string to a hue value 0360 for avatar coloring. */
function nameToHue(name: string): number {
let hash = 0;
for (let i = 0; i < name.length; i++) {
hash = name.charCodeAt(i) + ((hash << 5) - hash);
}
return Math.abs(hash) % 360;
}
/** Format milliseconds as mm:ss. */
function formatDuration(ms: number): string {
if (!ms || ms <= 0) return '';
@@ -1734,7 +1726,6 @@ export class ExploreView extends ViewLifecycleMixin(LitElement) {
: nothing}
<div class="horizontal-row">
${artists.map((a) => {
const hue = nameToHue(a.name);
return html`
<div
class="artist-card"
@@ -1750,7 +1741,7 @@ export class ExploreView extends ViewLifecycleMixin(LitElement) {
>
<div
class="artist-avatar"
style="background: hsl(${hue}, 45%, 35%)"
style="background: ${avatarBackground(a.name)}"
>
${this.artistImageCache.get(a.mbid)
? html`<img
@@ -132,7 +132,7 @@ export class JobDetailsDrawer extends LitElement {
}
.stage.error {
color: #ff6b6b;
color: #ff8787;
}
.stage-count {
@@ -144,7 +144,7 @@ export class JobDetailsDrawer extends LitElement {
.stage-error {
grid-column: 2 / -1;
font-size: var(--yj-text-sm);
color: #ff6b6b;
color: #ff8787;
overflow-wrap: anywhere;
}
+1 -1
View File
@@ -154,7 +154,7 @@ export const jobStateStyles = css`
}
.tone-danger {
--job-tone: #ff6b6b;
--job-tone: #ff8787;
}
.tone-success {
@@ -153,7 +153,7 @@ export class JobIndicator extends LitElement {
width: 6px;
height: 6px;
border-radius: 50%;
background: #ff6b6b;
background: #ff8787;
flex-shrink: 0;
}
+1 -1
View File
@@ -132,7 +132,7 @@ export class JobLogView extends LitElement {
}
.entry.error .message {
color: #ff6b6b;
color: #ff8787;
}
.detail {
+2 -2
View File
@@ -180,7 +180,7 @@ export class JobRow extends LitElement {
.error {
margin-top: 0.45em;
font-size: var(--yj-text-sm);
color: #ff6b6b;
color: #ff8787;
overflow-wrap: anywhere;
}
@@ -214,7 +214,7 @@ export class JobRow extends LitElement {
}
button.danger:hover:not(:disabled) {
color: #ff6b6b;
color: #ff8787;
}
button:disabled {
+1 -1
View File
@@ -201,7 +201,7 @@ export class JobsView extends ViewLifecycleMixin(LitElement) {
}
button.action.danger {
color: #ff6b6b;
color: #ff8787;
border-color: rgba(255, 107, 107, 0.35);
}
@@ -287,7 +287,7 @@ export class SmartPlaylistEditor extends LitElement {
}
.remove-btn:hover {
color: #ff6b6b;
color: #ff8787;
background: rgba(255, 107, 107, 0.1);
}
@@ -411,7 +411,7 @@ export class SmartPlaylistEditor extends LitElement {
.preview-error {
font-size: var(--yj-text-sm);
color: #ff6b6b;
color: #ff8787;
padding: 6px 0;
}
+39 -5
View File
@@ -20,7 +20,7 @@ type Subscriber = () => void;
* Shade palettes keyed by BackgroundShade.
* Each defines the base grayscale ramp used throughout the UI.
*/
interface ShadePalette {
export interface ShadePalette {
bgBase: string;
bgSurface: string;
bgElevated: string;
@@ -34,7 +34,36 @@ interface ShadePalette {
selectionBg: string;
}
const SHADE_PALETTES: Record<BackgroundShade, ShadePalette> = {
/**
* The grayscale ramps, and the one rule that constrains them.
*
* `textTertiary` used to be `#888888` on both dark ramps and `#868e96`
* on the light one, which `a11y.md` flagged as "borderline" from a hand
* calculation and parked as "worth measuring before planning".
* Measured, against the rendered app and then across all three ramps:
* it failed WCAG AA in **nine of twelve** text/surface combinations,
* as low as 2.31:1 on dark's overlay and 2.55:1 on light's. Not
* borderline — the app's most-used secondary text colour, failing on
* every view, and the light ramp (which the audit never considered) was
* the worst of the three.
*
* So: **every text colour clears 4.5:1 against every surface it can sit
* on**, and `theme-contrast.test.ts` computes that from this table
* rather than trusting it. Two things decided the values.
*
* `bgOverlay` is not a text surface on the dark ramp. Sizing tertiary
* to clear 4.5 against `#495057` needs `#c0c0c0`, which is *lighter
* than secondary* — an inverted hierarchy is a worse answer than the
* problem. Tertiary is sized to `bgElevated` there, and the one place
* that did put text on the overlay (the downloads notice) uses
* `textPrimary`, which clears 8.18:1.
*
* And the hue is kept. The light ramp's tertiary is a blue-grey, so it
* darkens along its own hue to `#5c636a` rather than flattening to a
* neutral that would have passed just as well and looked like a
* different palette.
*/
export const SHADE_PALETTES: Record<BackgroundShade, ShadePalette> = {
darker: {
bgBase: '#000000',
bgSurface: '#121212',
@@ -42,7 +71,8 @@ const SHADE_PALETTES: Record<BackgroundShade, ShadePalette> = {
bgOverlay: '#2a2a2a',
textPrimary: '#ffffff',
textSecondary: '#b3b3b3',
textTertiary: '#888888',
// 4.05:1 on bgOverlay at #888888.
textTertiary: '#949494',
border: '#333333',
borderSubtle: '#222222',
hoverOverlay: 'rgba(255, 255, 255, 0.05)',
@@ -55,7 +85,9 @@ const SHADE_PALETTES: Record<BackgroundShade, ShadePalette> = {
bgOverlay: '#495057',
textPrimary: '#ffffff',
textSecondary: '#b3b3b3',
textTertiary: '#888888',
// 4.35:1 on bgSurface and 3.25:1 on bgElevated at #888888 — the
// measured version of the audit's estimate, on every view.
textTertiary: '#a6a6a6',
border: '#444444',
borderSubtle: '#333333',
hoverOverlay: 'rgba(255, 255, 255, 0.05)',
@@ -68,7 +100,9 @@ const SHADE_PALETTES: Record<BackgroundShade, ShadePalette> = {
bgOverlay: '#dee2e6',
textPrimary: '#212529',
textSecondary: '#495057',
textTertiary: '#868e96',
// 3.32:1 at best and 2.55:1 at worst at #868e96 — the light ramp
// failed on all four of its own surfaces.
textTertiary: '#5c636a',
border: '#ced4da',
borderSubtle: '#dee2e6',
hoverOverlay: 'rgba(0, 0, 0, 0.05)',
+36
View File
@@ -0,0 +1,36 @@
/**
* The background for a letter avatar, derived from a name.
*
* Three call sites drew `hsl(nameToHue(name), 45%, 35%)` behind white
* initials, from two copies of the same hash function. Measured across
* all 360 hues: **35 of them** — the yellow-green band from about 53°
* to 88° — put white text below 4.5:1, bottoming out at 4.08:1. Which
* artists those were depended entirely on how their names hashed, so
* the app had a contrast failure that came and went with the search
* results, and the two instances that turned up in a sweep were not the
* finding.
*
* 32% lightness clears every hue with a floor of 4.75:1, so the fix is
* a property of the generator rather than of any colour it generates.
* `avatar-color.test.ts` walks all 360.
*/
/** Hash a string to a hue value 0360. */
export function nameToHue(name: string): number {
let hash = 0;
for (let i = 0; i < name.length; i++) {
hash = name.charCodeAt(i) + ((hash << 5) - hash);
}
return Math.abs(hash) % 360;
}
/** Saturation and lightness are shared so the floor above holds. */
export const AVATAR_SATURATION = 45;
export const AVATAR_LIGHTNESS = 32;
/** The `background` value for a name's avatar. */
export function avatarBackground(name: string): string {
return `hsl(${nameToHue(name)}, ${AVATAR_SATURATION}%, ${AVATAR_LIGHTNESS}%)`;
}
@@ -0,0 +1,77 @@
/**
* A letter avatar's background clears 4.5:1 against white for *every*
* hue it can generate.
*
* The two failures a rendered sweep found were not the finding. The
* generator was `hsl(hue, 45%, 35%)`, and 35 of the 360 hues — the
* yellow-green band — put white initials below 4.5:1, bottoming out at
* 4.08:1. Which artists those were depended on how their names hashed,
* so the failure came and went with the search results.
*
* So this walks all 360 rather than sampling: a generator's contrast is
* a property of the generator, and checking the instances that happened
* to be on screen is how it stayed broken.
*/
import { describe, expect, it } from 'vitest';
import { avatarBackground, nameToHue } from '@utils/avatar-color';
/** Resolve an `hsl(...)` string to sRGB via the browser's own parser. */
function toRgb(color: string): [number, number, number] {
const probe = document.createElement('div');
probe.style.color = color;
document.body.append(probe);
const computed = getComputedStyle(probe).color;
probe.remove();
const [r, g, b] = computed
.slice(computed.indexOf('(') + 1, computed.indexOf(')'))
.split(/[,\s/]+/)
.filter(Boolean)
.map(Number) as [number, number, number];
return [r, g, b];
}
function contrastWithWhite(color: string): number {
const channels = toRgb(color).map((v) => v / 255);
const [r, g, b] = channels.map((v) =>
v <= 0.03928 ? v / 12.92 : ((v + 0.055) / 1.055) ** 2.4,
) as [number, number, number];
const l = 0.2126 * r + 0.7152 * g + 0.0722 * b;
return 1.05 / (l + 0.05);
}
describe('avatar colours', () => {
it('clears 4.5:1 against white at every hue', () => {
const ratios = Array.from({ length: 360 }, (_, hue) =>
contrastWithWhite(`hsl(${hue}, 45%, 32%)`),
);
expect(Math.min(...ratios)).toBeGreaterThanOrEqual(4.5);
});
// The generator is only safe if every name lands on one of those hues,
// which is the half a hue-only sweep cannot see.
it('generates only hues in that range', () => {
const names = ['Eno', 'BTS', 'Aurora Fields', '', 'ザ・バンド', 'x'.repeat(200)];
const hues = names.map((n) => nameToHue(n));
expect(hues.every((h) => Number.isInteger(h) && h >= 0 && h < 360)).toBe(
true,
);
});
it('is the same colour for the same name', () => {
expect(avatarBackground('Aurora Fields')).toBe(
avatarBackground('Aurora Fields'),
);
});
});
@@ -0,0 +1,86 @@
/**
* Every text colour clears WCAG AA against every surface it can sit on,
* on all three background ramps.
*
* `a11y.md` flagged one pair as "borderline (≈4.1:1) but that needs a
* real measurement", and plan 007 parked it as "worth measuring before
* planning". Measured: it failed in **nine of twelve** combinations,
* as low as 2.31:1, and the light ramp — which the audit never looked
* at — was the worst of the three.
*
* This computes the ratios from the palette table rather than trusting
* it, because the failure mode is somebody picking a nice-looking hex.
* It is a unit test and not a sweep of the rendered app on purpose: the
* ramps are pure data, the arithmetic is exact, and a DOM sweep can
* only ever check the pairs that happen to be on screen — which is how
* the light ramp went unexamined in the first place.
*/
import { describe, expect, it } from 'vitest';
import { SHADE_PALETTES } from '@store/theme-store';
import type { ShadePalette } from '@store/theme-store';
/** WCAG 2.1 relative luminance. */
function luminance(hex: string): number {
const h = hex.replace('#', '');
const channels = [0, 2, 4].map((i) => parseInt(h.slice(i, i + 2), 16) / 255);
const [r, g, b] = channels.map((v) =>
v <= 0.03928 ? v / 12.92 : ((v + 0.055) / 1.055) ** 2.4,
) as [number, number, number];
return 0.2126 * r + 0.7152 * g + 0.0722 * b;
}
function contrast(a: string, b: string): number {
const [hi, lo] = [luminance(a), luminance(b)].sort((x, y) => y - x) as [
number,
number,
];
return (hi + 0.05) / (lo + 0.05);
}
const TEXT = ['textPrimary', 'textSecondary', 'textTertiary'] as const;
/**
* `bgOverlay` is deliberately absent for tertiary on the dark ramp.
* Clearing 4.5:1 against `#495057` needs a grey lighter than
* `textSecondary`, and an inverted hierarchy is a worse answer than the
* problem — so nothing puts tertiary text there, and the one component
* that put *secondary* text on an overlay uses primary now.
*/
const SURFACES: Record<(typeof TEXT)[number], (keyof ShadePalette)[]> = {
textPrimary: ['bgBase', 'bgSurface', 'bgElevated', 'bgOverlay'],
textSecondary: ['bgBase', 'bgSurface', 'bgElevated'],
textTertiary: ['bgBase', 'bgSurface', 'bgElevated'],
};
describe('theme contrast', () => {
const cases = Object.entries(SHADE_PALETTES).flatMap(([shade, palette]) =>
TEXT.flatMap((text) =>
SURFACES[text].map((surface) => ({
shade,
text,
surface,
ratio: contrast(palette[text], palette[surface]),
})),
),
);
it.each(cases)('$shade: $text on $surface clears 4.5:1', ({ ratio }) => {
expect(ratio).toBeGreaterThanOrEqual(4.5);
});
// Sizing tertiary to clear 4.5:1 on every surface is easy and wrong:
// it produces a tertiary lighter than secondary on the dark ramp. The
// ramp has to stay a ramp, or "tertiary" stops meaning anything.
it.each(Object.entries(SHADE_PALETTES))(
'%s keeps the text ramp ordered',
(_shade, palette) => {
const steps = TEXT.map((t) => contrast(palette[t], palette.bgSurface));
expect(steps).toEqual([...steps].sort((a, b) => b - a));
},
);
});