--- name: Carloku description: The hosted CARLOS platform — the category-standard app-platform page, out-finished in one purple. colors: carloku-purple: "#5b3e96" carloku-purple-deep: "#4c3380" carloku-purple-soft: "rgba(91, 62, 150, 0.08)" lifted-purple: "#b394f2" button-purple-dark-scheme: "#6a48c8" ink: "#1d1927" moon-ink: "#f2eff8" paper: "#ffffff" night: "#0e0c13" paper-tint: "#f8f7fb" night-tint: "#14111c" muted: "#5d5570" muted-dark-scheme: "#a9a0c2" band-purple: "#221a35" band-purple-dark-scheme: "#261b44" terminal-black: "#120f1a" terminal-chrome: "#1b1626" terminal-ink: "#ede9f7" terminal-out: "#9d93b8" terminal-ok-green: "#7ee2a8" hairline: "rgba(29, 25, 39, 0.1)" hairline-strong: "rgba(29, 25, 39, 0.16)" hairline-dark-scheme: "rgba(242, 239, 248, 0.09)" typography: display: fontFamily: "Geist, ui-sans-serif, system-ui, -apple-system, sans-serif" fontSize: "clamp(2.6rem, 5.4vw, 4.1rem)" fontWeight: 680 lineHeight: 1.04 letterSpacing: "-0.032em" headline: fontFamily: "Geist, ui-sans-serif, system-ui, -apple-system, sans-serif" fontSize: "clamp(1.7rem, 3vw, 2.3rem)" fontWeight: 650 lineHeight: 1.15 letterSpacing: "-0.025em" title: fontFamily: "Geist, ui-sans-serif, system-ui, -apple-system, sans-serif" fontSize: "1.08rem" fontWeight: 620 letterSpacing: "-0.01em" body: fontFamily: "Geist, ui-sans-serif, system-ui, -apple-system, sans-serif" fontSize: "1rem" fontWeight: 400 lineHeight: 1.6 lede: fontFamily: "Geist, ui-sans-serif, system-ui, -apple-system, sans-serif" fontSize: "1.17rem" fontWeight: 400 lineHeight: 1.65 mono: fontFamily: "Geist Mono, ui-monospace, SFMono-Regular, Menlo, Consolas, monospace" fontSize: "0.86rem" fontWeight: 400 lineHeight: 1.75 rounded: chip: "0.3em" control: "0.65rem" frame: "0.85rem" spacing: gutter: "1.5rem" section: "5.5rem" band: "6rem" close: "7rem" components: button-primary: backgroundColor: "{colors.carloku-purple}" textColor: "#ffffff" rounded: "{rounded.control}" padding: "0.72rem 1.4rem" button-primary-hover: backgroundColor: "{colors.carloku-purple-deep}" button-quiet: textColor: "{colors.ink}" rounded: "{rounded.control}" padding: "0.72rem 1.4rem" head-cta: textColor: "{colors.carloku-purple}" rounded: "0.55rem" padding: "0.42rem 0.95rem" code-chip: backgroundColor: "{colors.carloku-purple-soft}" textColor: "{colors.carloku-purple-deep}" rounded: "{rounded.chip}" padding: "0.12em 0.4em" terminal-frame: backgroundColor: "{colors.terminal-black}" rounded: "{rounded.frame}" ---

Design System: Carloku

Overview

Creative North Star: "The Quiet Standard"

Carloku's site is the category-standard app-platform page — hero left, terminal right, three steps, feature list, full-bleed band, closing CTA — played completely straight and won on finish, not on invention. Every surface is white (or near-black) paper crossed by hairline borders; a single purple carries the entire brand voice; Geist and Geist Mono do all the talking. The one theatrical object is the hero terminal, which types a real ship → promote → rollback session and wears the same dark clothes in both color schemes.

The system is genuinely two-scheme: prefers-color-scheme drives a full token swap (white-with-purple light, near-black-with-purple dark) declared as CSS custom properties on :root. Both schemes are required, not optional. The build is dependency-free by rule — no build step, no external requests, self-hosted variable fonts only, vanilla JS — so the token layer is the stylesheet; there is no second source of truth.

Key Characteristics:

• One accent purple per scheme; its rarity is its authority.
• Hairline borders (1px, low-alpha ink) do almost all the structural work; shadows exist only under framed media and the primary button.
• Variable-font weights at non-standard steps (480, 560, 580, 620, 650, 680) — the ramp is tuned, not defaulted.
• A terminal that never changes scheme: fixed dark tokens (--term-*) with no dark-mode override.
• Exactly one deep-purple full-bleed band per page.
• Motion is small and fast (120–160ms ease-out) with a total prefers-reduced-motion kill switch.

Colors

Two mirrored monochrome-plus-purple schemes: purple is the only voice, everything else is ink, paper, and hairlines.

Primary

• Carloku Purple (#5b3e96): the light-scheme accent and primary button fill; also the hardcoded brand-mark fill in the logo SVG and favicon. Used for links, focus outlines, ::selection, step numerals, and feature-icon strokes.
• Carloku Purple Deep (#4c3380): hover state of the primary button; text color of inline code chips (as --accent-ink).
• Carloku Purple Soft (rgba(91, 62, 150, 0.08)): the accent at 8% alpha — background of code chips, icon tiles, step numerals, and quiet-button hover washes. In dark scheme it becomes the lifted purple at 10% alpha.
• Lifted Purple (#b394f2): the dark-scheme accent (links, focus, icons) — and, in both schemes, the terminal's prompt color and caret. Dark-scheme buttons use their own fill (#6a48c8, hover #7d5cdb) because the lifted accent is too light to carry white text.

Neutral

• Ink (#1d1927): body text, light scheme — a purple-cast near-black, never pure #000. Dark-scheme ink is Moon Ink (#f2eff8).
• Paper (#ffffff) / Night (#0e0c13): page backgrounds. Each has a tint sibling (#f8f7fb / #14111c) used only for the alternating .tint section.
• Muted (#5d5570 light / #a9a0c2 dark): all secondary copy — ledes, feature paragraphs, footer. A step fainter (--faint: #6e6880 / #928aab) handles captions and asides.
• Hairlines (rgba(29,25,39,0.1) light / rgba(242,239,248,0.09) dark): every border on page surfaces; a -strong sibling at 0.16 alpha for quiet-button borders and note rules.

Terminal (scheme-fixed)

• Terminal Black (#120f1a) with chrome bar #1b1626: the terminal and dashboard-frame background in both schemes.
• Terminal Ink (#ede9f7) for typed commands, Terminal Out (#9d93b8) for program output, #8d84a6 for chrome titles and comments.
• Terminal OK Green (#7ee2a8): success lines only. This is the only non-purple hue in the entire system, and it exists only inside the terminal.

Band

• Band Purple (#221a35 light / #261b44 dark): the one full-bleed deep-purple section. It carries its own sub-palette: ink #f2eef9, muted #b9aed6, hairlines at 12–14% alpha of the band ink, and inverted buttons (band-ink fill, band-bg text).

Named Rules

The One Voice Rule. One purple per scheme carries links, focus, selection, buttons, and icons. No second accent hue ever appears on page surfaces; the terminal's green is terminal furniture, not a palette member. The Terminal Stays Dark Rule. --term-* tokens have no dark-scheme override. Anything framed as a terminal or console capture (.term, .dash-frame) sits on Terminal Black in both schemes. The No-Pure-Black Rule. Ink and backgrounds are always purple-cast (#1d1927, #0e0c13, #120f1a) — never #000.

Typography

Display/Body Font: Geist variable (with ui-sans-serif, system-ui fallback) — self-hosted woff2, weight axis 100–900, preloaded. Mono Font: Geist Mono variable (with ui-monospace, SFMono-Regular fallback) — commands, code chips, terminal, step numerals.

Character: One contemporary grotesk doing everything, differentiated by finely-tuned variable weights and progressively tighter tracking as size grows. Mono is the product's own voice — commands appear as incantations, never paragraphs.

Hierarchy

• Display (680, clamp(2.6rem, 5.4vw, 4.1rem), 1.04, -0.032em): the hero headline only; text-wrap: balance, with the sentence-final period in accent purple (.dot).
• Headline (650, clamp(1.7rem, 3vw, 2.3rem), 1.15, -0.025em): section h2s. The closing CTA scales it up (clamp(2rem, 4vw, 3rem)); guide-page h2s scale it down (1.45rem).
• Title (620, 1.08–1.12rem, -0.01em): feature and step h3s.
• Lede (400, 1.17rem, 1.65): hero standfirst in muted, max-width 34rem; section ledes at 1.08rem, max-width 38rem. Always text-wrap: pretty.
• Body (400, 1rem, 1.6): default. Guide prose is capped at 42rem; footer at 44rem.
• Mono (400, 0.86–0.88rem, 1.75): terminal and pre blocks, with font-variant-numeric: tabular-nums in the terminal. Inline code chips run at 0.88em of their context.

Named Rules

The Off-Grid Weight Rule. Weights come from the variable axis at tuned steps — 480 (nav), 560 (emphasis/mono), 580 (buttons), 620/650/680 (titles up to display) — never the flat 400/700 defaults. The Tighter-As-Bigger Rule. Tracking tightens with size: -0.01em at title, -0.025em at headline, -0.032em at display; body stays normal. The Purple Period Rule. A display or closing headline may end its sentence with an accent-colored full stop (.dot) — the accent's only appearance inside running display type.

Layout

A single centered column, max-width 72rem (--wrap) with 1.5rem side gutters; prose pages narrow to 50rem (.wrap.narrow). Sections stack at a 5.5rem vertical rhythm (band 6rem, closing CTA 7rem), separated not by rules but by alternating backgrounds: plain, tint (with top+bottom hairlines), band. Two-column grids do the feature work — hero at 1.05fr / 1fr with 4.5rem gap, quiet-grid at 0.92fr / 1.08fr — always with minmax(0, …) to protect the terminal's overflow. Steps run three-across.

Two breakpoints, both max-width: 62rem collapses every grid to one column and compresses section padding to 4rem; 44rem rewraps the sticky header (nav drops to a full-width second row). The header itself is 4rem tall, sticky, background at 82% opacity over 12px backdrop blur, and earns its bottom hairline only after 8px of scroll.

Elevation & Depth

Essentially flat: hairline borders and background-tint shifts convey nearly all structure. Shadows exist in exactly two places — under framed dark media (terminal, dashboard frame) and under the primary button — and both are soft, large-radius, purple-cast ambient washes, never hard offsets.

Shadow Vocabulary

• Frame shadow (--shadow: 0 1px 2px rgba(20,12,40,0.05), 0 12px 32px -12px rgba(20,12,40,0.18) light; 0 1px 2px rgba(0,0,0,0.4), 0 16px 40px -16px rgba(0,0,0,0.55) dark): terminal and dashboard frames only.
• Button shadow (0 1px 2px rgba(20,12,40,0.2), 0 6px 16px -6px color-mix(in srgb, var(--btn-bg) 55%, transparent)): primary buttons on page surfaces; removed inside the band.

Named Rules

The Two-Shadows Rule. Only framed dark media and the primary button cast shadows. Cards, sections, the header, and everything else are flat, defined by hairlines and tint shifts.

Shapes

Soft-but-businesslike radii in three sizes: 0.3em for inline chips, ~0.55–0.7rem for controls (buttons 0.65rem, header CTA 0.55rem, pre 0.7rem), 0.85rem for the big framed objects (terminal, dashboard). Step numerals, terminal traffic-light dots, and icon-tile contents use circles; icon tiles themselves are 2.4rem squares at 0.6rem radius. Borders are always 1px hairlines — there are no 2px+ borders and no hard-cornered rectangles anywhere. The brand mark is a rounded square (rx 14/64) holding a small rack of rounded slabs, every row the same width (one server, two apps, four instances), each with a short down-right thickness — the same soft-cornered geometry as the page. For white backgrounds there is an inverted version, purple on a white tile, in brand/mark-light.svg; the site does not serve it.

Components

Buttons

• Shape: softly rounded (0.65rem), inline-flex, 0.72rem × 1.4rem padding, weight 580.
• Primary: Carloku Purple fill (#5b3e96 light / #6a48c8 dark), white text, purple-cast shadow. Hover deepens the fill (#4c3380 / #7d5cdb). Inside the band it inverts: band-ink fill, band-bg text, no shadow, hover to pure white.
• Quiet: transparent with a strong-hairline border and ink text; hover turns border and text accent-purple over an accent-soft wash.
• Active: translateY(1px) press. Focus: 2px accent outline, 3px offset (global rule for all links and buttons).
• Header CTA: a smaller quiet-button variant (0.42rem × 0.95rem, 0.55rem radius) in accent color.

Chips (inline code)

• Style: Geist Mono at 0.88em on an accent-soft wash, accent-ink text, 0.3em radius, 0.12em × 0.4em padding. This is how the three commands appear in prose.

Cards / Containers

There are no boxed cards. "Cards" are borderless grid cells (steps, features) separated by hairline rules between siblings (li + li { border-top }) and by whitespace. Framed containers exist only for dark media (see Terminal).

Navigation

• Sticky translucent header (82% bg over 12px blur), 4rem tall; brand at weight 640 with the SVG mark; links in muted at 0.95rem/weight 480, hover to ink (color transition only, 120ms). Scroll past 8px adds the bottom hairline. Below 44rem the nav wraps to a second full-width row.

Terminal (signature component)

Terminal Black frame, 0.85rem radius, hairline rgba(255,255,255,0.08) border, frame shadow. Chrome bar (#1b1626) holds three 0.68rem dots drawn in title-color at 28% opacity plus a mono-ish title (#8d84a6, 0.78rem). Body is Geist Mono 0.86rem at 1.75 line-height, tabular numerals, min-height 17.5rem. Line grammar: commands in terminal-ink with a $ prompt in lifted purple (weight 560, injected via ::before), output in terminal-out, comments in title-color, success in OK green, and a blinking lifted-purple caret (1.1s steps). On load the session types itself once (14ms/char, staged line delays, vanilla JS) — skipped entirely under reduced motion. The same frame + chrome bar wraps the dashboard screenshot (.dash-frame), which swaps light/dark captures via <picture> while the frame stays dark.

Feature list items

Two-column grid rows (icon auto / text 1fr, 1.15rem gap), 1.35rem vertical padding, hairline rules between rows. Icons are inline 24px-viewBox stroke SVGs (stroke-width 2, round caps/joins — vendored Lucide-style, never icon fonts or CDNs) at 1.25rem inside 2.4rem accent-soft tiles.

Guide article (get-started)

Hairline-separated sections at 2.4rem padding; pre blocks in the terminal's clothes (Terminal Black, terminal ink, 0.7rem radius); asides as .note — a single left hairline-strong rule, faint text, no background.

Do's and Don'ts

Do:

• Do keep both color schemes complete: every new token needs a light value on :root and a dark value in the prefers-color-scheme: dark block, plus a theme-color meta if it changes page chrome.
• Do draw structure with hairlines and tint shifts (--line, --bg-tint), reserving shadows for framed dark media and the primary button.
• Do put anything terminal- or console-shaped on the fixed --term-* palette in both schemes.
• Do use tuned variable weights (480/560/580/620/650/680) and tighter tracking as type grows.
• Do keep motion at 120–160ms ease-out, and gate all animation and smooth scroll behind prefers-reduced-motion (the global kill switch already exists — don't bypass it).
• Do stay dependency-free: no build step, no external requests, self-hosted fonts only, inline SVG icons, vanilla JS.

Don't:

• Don't introduce a second accent hue on page surfaces; the terminal's OK green never leaves the terminal.
• Don't use pure #000 or #fff for ink/dark backgrounds — near-blacks are purple-cast (#1d1927, #0e0c13, #120f1a). (The one white exception: text on purple button fills.)
• Don't box content in bordered cards; siblings separate with single hairline rules or whitespace.
• Don't add a second full-bleed purple band to a page — one per page is the ceiling.
• Don't use hard-offset shadows, borders heavier than 1px, or icon fonts/CDN icons.
• Don't let dark-scheme buttons use the lifted accent (#b394f2) as a fill; buttons keep their own deeper fills (#6a48c8/#7d5cdb) so white text stays legible.