Greys, type, radius, shadows, focus, dark mode and fills: the tokens every part uses.
The brand is black and white, so the foundations are a set of greys that switch with the theme, one type family in two cuts, and a small scale for corners and depth. Components use the semantic names (text-fg, bg-raised, border-line), never raw values, which is why nothing needs a dark: variant.
6 parts
Twelve semantic greys that switch with the theme, and six fixed brand values for the logo and brand panels.
import { useEffect, useRef, useState } from 'react'import { cx } from '@rchursin/components/cx'
/** * Every semantic colour, measured live in this browser: the value the swatch really paints and its * contrast against the surface. Switch the site theme and the numbers follow. */type Token = { name: string; swatch: string; role: string; text?: boolean; on?: 'inverse' }
// Utilities are written out in full so Tailwind can find them.const groups: { title: string; tokens: Token[] }[] = [ { title: 'Text', tokens: [ { name: 'fg', swatch: 'bg-fg', role: 'Headings, body text, icons', text: true }, { name: 'fg-2', swatch: 'bg-fg-2', role: 'Descriptions, inactive tabs', text: true }, { name: 'fg-3', swatch: 'bg-fg-3', role: 'Meta: hints, dates, mono labels', text: true }, ], }, {Geist for the interface and Geist Mono for labels, code and the wordmark, in the sizes the site and the kit really use.
/** * The type scale as the site and the product kit use it, largest first. Each row is the real * class list; the size labels are pixels / line height (in pixels, or as a multiple of the size). * (The two largest steps grow with the preview's width here; on pages they use sm: instead of @3xl:.) */const scale = [ { name: 'Display', spec: '36 → 56 · 600 · −0.035em', where: 'Page heroes', className: 'text-4xl font-semibold tracking-[-0.035em] text-balance @3xl:text-[3.5rem] @3xl:leading-[1.02]', sample: 'Tools for AI coding agents', }, { name: 'Title', spec: '32 → 40 · 600 · −0.03em', where: 'Library and project titles', className: 'text-[2rem] leading-[1.1] font-semibold tracking-[-0.03em] @3xl:text-[2.5rem]', sample: 'Colour and type', },Corner sizes from 4 to 24 px plus the 22 px app-icon tile, four elevation steps, and the brand’s Lift shadow.
/** * Four steps of elevation, one light source straight above. In light mode each step adds a * softer, wider shadow; in dark mode it is a lit top edge and a ring, with shadows only to ground it. */const steps = [ { n: 1, shadow: 'shadow-[var(--lux-shadow-1)]', name: 'Flat', where: 'Quiet cards, wells', cls: 'lux-card-flat' }, { n: 2, shadow: 'shadow-[var(--lux-shadow-2)]', name: 'Card', where: 'Cards, previews', cls: 'lux-card' }, { n: 3, shadow: 'shadow-[var(--lux-shadow-3)]', name: 'Hover', where: 'A card under the pointer', cls: 'lux-lift' }, { n: 4, shadow: 'shadow-[var(--lux-shadow-4)]', name: 'Float', where: 'Menus, popovers, dialogs', cls: 'lux-float' },]
export default function Elevation() { return ( <div className="@container w-full"> <ol className="grid grid-cols-2 gap-5 pb-10 @2xl:grid-cols-4"> {steps.map((s) => ( <li key={s.n} className={`flex min-h-32 min-w-0 flex-col justify-between gap-6 rounded-2xl bg-raised p-4 ${s.shadow}`}> <code className="font-mono text-[11.5px] text-fg-3">--lux-shadow-{s.n}</code> <span className="flex flex-col gap-0.5"> <span className="text-[15px] font-semibold tracking-[-0.01em] text-fg">{s.name}</span> <span className="text-[12.5px] text-fg-3">{s.where}</span> <code className="mt-1 font-mono text-[11.5px] text-fg-2">.{s.cls}</code> </span> </li> ))} </ol> </div> )}A 2px ring in the text colour, outside or inside the edge, plus the lit-metal buttons’ own ring. Keyboard only.
import { useState, type ReactNode } from 'react'import { cx } from '@rchursin/components/cx'import { Button, Switch } from '@rchursin/product/ui'
/** * The three focus rings. "Draw the rings" paints each one without focus so you can compare them; * turn it off and press Tab to see the real thing (they appear for the keyboard, not for clicks). */export default function FocusRings() { const [draw, setDraw] = useState(true) // What :focus-visible draws, copied as plain classes for the comparison const ring = draw && 'outline-2 outline-offset-2 outline-fg' const inset = draw && 'outline-2 -outline-offset-2 outline-fg' const rim = draw && 'outline-2 outline-offset-3 outline-[var(--lux-focus)]' const rimInverse = draw && 'outline-2 outline-offset-3 outline-[var(--lux-focus-inverse)]' const current = draw && 'outline-2 outline-offset-2 outline-current'
return ( <div className="@container flex w-full flex-col gap-6"> <Switch label="Draw the rings" hint="Off: press Tab to see them for real." checked={draw} onChange={setDraw} className="max-w-xs" />One class flips every token: on <html> for the whole page, or on any wrapper for one part of it.
import { Segmented } from '@rchursin/product/ui'import { useTheme, type ThemeChoice } from '@rchursin/product/lib/theme'
/** * The site's own theme switch, drawn with the Library's Segmented control. It changes the whole * page: the choice is saved, "System" follows the operating system, and the switch cross-fades. */export default function ThemeSwitch() { const { choice, resolved, setChoice } = useTheme() return ( <div className="flex w-full max-w-sm flex-col items-center gap-6"> <Segmented<ThemeChoice> label="Theme" value={choice} onChange={setChoice} options={[ { value: 'system', label: 'System', icon: 'monitor' }, { value: 'light', label: 'Light', icon: 'sun' }, { value: 'dark', label: 'Dark', icon: 'moon' }, ]} /> <dl className="grid w-full grid-cols-[auto_minmax(0,1fr)] gap-x-6 gap-y-2 rounded-xl bg-sunken px-4 py-3 text-[12.5px] ring-1 ring-line"> <dt className="text-fg-3">Saved choice</dt> <dd className="text-right font-mono text-fg">{choice}</dd> <dt className="text-fg-3">Showing</dt> <dd className="text-right font-mono text-fg">{resolved}</dd> <dt className="text-fg-3">On <html></dt> <dd className="text-right font-mono text-fg">{resolved === 'dark' ? 'class="dark"' : 'no class'}</dd> </dl> </div> )}Solid, hatched, outline and dashed: the second “colour” of a black-and-white interface, plus the dot-grid canvas.
import { PatternFill, PatternSwatch, patternText } from '@rchursin/product/calendar/patterns'import { SampleBadge } from '@rchursin/product/shell/layout'
/** * Four calendars told apart by fill, never by colour: solid, hatched, outline and dashed. * They read the same in greyscale, in print and for people who can't tell colours apart. */const events = [ { calendar: 'Team', pattern: 'solid', title: 'Design review', time: '10:00 – 11:00' }, { calendar: 'Focus', pattern: 'hatched', title: 'Deep work', time: '13:00 – 15:00' }, { calendar: 'Personal', pattern: 'outline', title: 'Dentist', time: '17:30 – 18:15' }, { calendar: 'Releases', pattern: 'dashed', title: 'Library release', time: 'All day' },] as const
export default function FillPatterns() { return ( <div className="@container flex w-full max-w-3xl flex-col gap-5"> <div className="flex flex-wrap items-center justify-between gap-3"> <ul aria-label="Calendars" className="flex flex-wrap gap-x-4 gap-y-2"> {events.map((e) => (Measuring… Contrast is against surface (on-inverse: against inverse).
fg–Headings, body text, iconsfg-2–Descriptions, inactive tabsfg-3–Meta: hints, dates, mono labelssurface–The page itselfraised–Cards, menus, dialogssunken–Wells: code blocks, read-only fieldsline–Hairlines between rowsline-strong–Control edges, outline chipshover–A row under the pointerselected–The current row or nav iteminverse–Tooltips, solid badgeson-inverse–Text on inverse--lux-shadow-1FlatQuiet cards, wells.lux-card-flat--lux-shadow-2CardCards, previews.lux-card--lux-shadow-3HoverA card under the pointer.lux-lift--lux-shadow-4FloatMenus, popovers, dialogs.lux-floatOff: press Tab to see them for real.
focus-ring2px, 2px outside. Links, tabs, chips, anything with room around it.focus-ring-inset2px, inside the edge. Rows that sit edge to edge in a clipped list.--lux-focus2px, 3px outside, on every lit-metal button. Clear of the silver rim.On an inverse panel the button ring flips to --lux-focus-inverse; for your own controls, follow the text colour.