Preview the prompt +
# Build brief — an original marketing website in the taste of On
> Reference: https://www.on.energy · UIDiscovery: https://uidiscovery.com/sites/on · captured 2026-09-22 at a 1440px desktop viewport (+ 390px iPhone shots) · [full page](https://uidiscovery.com/media/captures/on/full.webp) · [scroll video](https://uidiscovery.com/media/captures/on/preview.mp4)
## 1. Goal
Build an original marketing website for **[the user's brand]** that feels as considered as On — same structure, rhythm and polish, entirely new identity and content.
## 2. Originality rules
- Build an ORIGINAL design for the user's own brand in the same *taste* as On: structure, rhythm, hierarchy, palette mood and type pairing.
- Never reuse On's logo, name, product imagery, illustrations, icons, screenshots or copy. Write new copy for the user's product.
- If the user hasn't said what their product is, ask first (or use clearly marked placeholders like [Brand], [Product], [Audience]).
- Reference screenshots are for looking at, not for embedding or tracing.
## 3. The taste, in short
- On (on.energy): Developer Tools marketing website, dark, minimal, award winner.
- 5 sections: Hero → Content → Features → Testimonials → Features.
- Spacing: about a screen per idea (median section ≈779px).
- Hero headline: 5 words — short and punchy; keep yours under ~9.
- Type: one family (Univers Next Pro). Imagery: mostly typography with little or no imagery.
## 4. Page structure (top to bottom)
### 1. Hero — state what the product is and for whom in one glance, and offer the primary action.
- Layout: headline-led stack: eyebrow → H1 → supporting line → actions, with a visual beside or below. About one full screen (900px at 1440), page background; 3 image/graphics; 1 text link instead of buttons.
- Slots: Eyebrow / announcement pill (optional); H1 (~5 words, like the reference); Supporting line, 1–2 sentences; Text link action; Hero visual (see image plan).
- Topic (tone/length only — never reuse): “Perfect Power for AI Factories.”
- [Screenshot](https://uidiscovery.com/media/captures/on/s-01.webp) · imagery: slot 1
### 2. Content — supporting content that deepens one idea.
- Layout: text + media block. About one full screen (890px at 1440), page background; no images (type-led); no interactive controls.
- Slots: Heading; Body copy.
- [Screenshot](https://uidiscovery.com/media/captures/on/s-02.webp)
### 3. Features — explain the key benefits, grouped so each can be scanned in seconds.
- Layout: section title over a grid or alternating rows of benefit items. About one full screen (779px at 1440), page background; 8 images/icons (a set of cards or a small gallery); no interactive controls.
- Slots: Section title; 2 items: icon or visual + short title + 1–2 line description.
- [Screenshot](https://uidiscovery.com/media/captures/on/s-04.webp)
### 4. Testimonials — let real customers make the case in their own words.
- Layout: quote cards or a featured quote with name, role and avatar. Half to one screen (684px at 1440), own light band #eeeeee; 12 images/icons (a set of cards or a small gallery); 9 buttons (tabs, toggles or per-card actions).
- Slots: Section title; 6 quotes: 1–3 sentences, name, role, company, avatar; Use real customer quotes only.
- Topic (tone/length only — never reuse): “Testimonials”
- [Screenshot](https://uidiscovery.com/media/captures/on/s-05.webp)
### 5. Features — explain the key benefits, grouped so each can be scanned in seconds.
- Layout: section title over a grid or alternating rows of benefit items. Half to one screen (547px at 1440), own dark band #202020; 3 image/graphics; 1 text link instead of buttons.
- Slots: Section title (~12 words, like the reference); 2 items: icon or visual + short title + 1–2 line description; Text link action.
- Topic (tone/length only — never reuse): “O U R E X P E R T I S E”
- [Screenshot](https://uidiscovery.com/media/captures/on/s-06.webp) · imagery: slot 2
Inner pages also captured (Product, About, Blog, Contact, Security): https://uidiscovery.com/sites/on?view=pages
## 5. Design system
### Colour
| Role | Hex | Use | Contrast on background |
|---|---|---|---|
| background | `#000000` | page background | — |
| foreground | `#eeeeee` | body text, headings | 18.1:1 |
| accent | `#eeeeee` | none captured — monochrome. Primary buttons invert (foreground fill, background text); add your brand colour only for small highlights | — |
| surface | `#202020` | cards, inputs, alternate bands | text on it 14.0:1 |
| muted | `#7d7d7d` | secondary text, borders | 5.1:1 |
Captured palette: `#000000` `#eeeeee` `#202020` `#afafaf` `#7d7d7d` `#4b4b4b`. Section bands top→bottom: `#000000` → `#eeeeee` → `#202020`. Roles are assigned automatically — sanity-check them against the screenshot. Keep the palette's *mood* (dark, neutral, desaturated) and proportions; swap the accent for the user's brand colour.
### Tokens
```css
:root {
--background: #000000;
--foreground: #eeeeee;
--accent: #eeeeee;
--surface: #202020;
--muted: #7d7d7d;
--font-heading: "Inter", ui-sans-serif, system-ui, sans-serif;
--font-body: "Inter", ui-sans-serif, system-ui, sans-serif;
--radius: 12px; /* calibrate from the screenshot */
}
/* Tailwind v4 — in globals.css after @import "tailwindcss"; */
@theme {
--color-background: var(--background);
--color-foreground: var(--foreground);
--color-accent: var(--accent);
--color-surface: var(--surface);
--color-muted: var(--muted);
--font-heading: var(--font-heading);
--font-sans: var(--font-body);
}
```
### Typography
- Headings: **Inter** (Google Fonts) — reference uses Univers Next Pro. “Univers Next Pro” is likely a custom or licensed face. Inter is a neutral stand-in — pick a closer free match by eye from the screenshot.
- Body: same family — a single-family system; create contrast with size and weight, not a second face.
- Scale (starting point, sizes weren't measured — calibrate against the 1440px screenshot): display clamp(2.75rem, 6vw, 5rem), h2 clamp(1.75rem, 3vw, 2.5rem), h3 1.25rem, body 1rem–1.125rem / 1.6, small 0.875rem. Headings: tight tracking (-0.02em), line-height 1.05–1.15.
### Spacing & rhythm
Sections run ≈779px tall at 1440 (median; range 547–900px, captures cap at 1700px) — roughly a screen per idea. Start with 96–120px vertical padding per section on desktop and about two-thirds of that on mobile. The background changes 2 times down the page — use band changes to mark chapters. 8px spacing grid, 1200–1280px max content width, 24px (mobile) / 32–48px (desktop) gutters.
### Shape, depth & theme
Flat surfaces, hairline 1px borders in the muted colour, small radii (4–8px), almost no shadow; on dark, separate layers with 1px borders at ~8–12% white and soft glows instead of drop shadows; expressive layout and motion are part of the appeal — study the scroll video, but keep motion subtle and respect prefers-reduced-motion. Read exact corner radius, border and shadow treatment from the screenshots. Dark-first; for a light mode swap background ↔ foreground, lighten the surface, keep the accent and re-check contrast.
## 6. Imagery plan
Measured from 3 section screenshots: mostly **typography with little or no imagery** (dark, neutral, desaturated, Developer Tools). Still glance at the linked screenshots to match the exact mood.
### Slot 1 · 1. Hero → abstract 3D / gradient (uncertain)
- Dark Developer Tools section with a few graphics — typically abstract 3D/gradient art or a product shot. Count: a set of ~3 in one consistent style. Aspect: 16:9 full-bleed (or 21:9). Look first: [ref 1](https://uidiscovery.com/media/captures/on/s-01.webp)
- **Stock** — “abstract dark gradient 3d”: [Unsplash](https://unsplash.com/s/photos/abstract-dark-gradient-3d?orientation=landscape) · [Pexels](https://www.pexels.com/search/abstract%20dark%20gradient%203d/?orientation=landscape) · [Pixabay](https://pixabay.com/images/search/abstract%20dark%20gradient%203d/?orientation=horizontal)
- **Generate** — `Abstract 3D render: soft, glossy glass-like shapes and a smooth gradient in #7d7d7d and #202020 on a #000000 background. Lighting: low-key, moody directional light with deep shadows; neutral, desaturated tone. Minimal and calm, generous negative space on one side for text. Aspect ratio 16:9. No text, no letters, no logos, no watermarks, no brand marks or trademarked products, no recognisable real people.`
### Slot 2 · 5. Features → product UI (uncertain)
- Developer Tools features with 3 image elements — most likely product UI screenshots/mockups plus icons. Count: a set of ~3 in one consistent style. Aspect: 4:3. Look first: [ref 1](https://uidiscovery.com/media/captures/on/s-06.webp)
- **Stock** — “laptop blank screen minimal desk”: [Unsplash](https://unsplash.com/s/photos/laptop-blank-screen-minimal-desk?orientation=landscape) · [Pexels](https://www.pexels.com/search/laptop%20blank%20screen%20minimal%20desk/?orientation=landscape) · [Pixabay](https://pixabay.com/images/search/laptop%20blank%20screen%20minimal%20desk/?orientation=horizontal)
- **Generate** — `Product-shot backdrop for a UI screenshot: smooth dark gradient from #000000 to #202020 with a soft #7d7d7d glow behind the centre, subtle floor shadow, empty centre area where a screenshot will be placed. Lighting: low-key, moody directional light with deep shadows. Aspect ratio 4:3. No text, no letters, no logos, no watermarks, no brand marks or trademarked products, no recognisable real people. No UI elements.`
- Build the UI itself in HTML/CSS with realistic sample data from YOUR product (or screenshot your real app). Don't generate UI as an image and don't reuse the reference's screenshots. Stock/AI is only for the backdrop or device frame.
- **No imagery (type-led)** — 2. Content, 3. Features, 4. Testimonials: No imagery needed — type, spacing and colour do the work. If the screenshot shows a background graphic, rebuild it in CSS (gradient, grid, noise) or a short muted video, not a stock photo.
### If the screenshots show a different style
Open the refs first and name what you actually see (photo / product UI / illustration / abstract gradient or 3D / type only). If it differs from the guess, switch routes — UI is built in code, type-only needs no image, otherwise:
- **photography** — generate `Photograph: abstract gradient mesh. Composition: wide shot, subject off-centre to one side, generous clean negative space for the headline. Lighting: low-key, moody directional light with deep shadows. Neutral, desaturated colour grade that sits on #000000, #eeeeee, #202020. Photorealistic, natural textures, shallow depth of field, 35mm lens. Aspect ratio 16:9. No text, no letters, no logos, no watermarks, no brand marks or trademarked products, no recognisable real people.` · stock: [“abstract gradient mesh dark” on Unsplash](https://unsplash.com/s/photos/abstract-gradient-mesh-dark?orientation=landscape) (same query works on Pexels/Pixabay)
- **illustration** — generate `Flat vector illustration: abstract gradient mesh, friendly simplified shapes, limited palette of #000000, #eeeeee, #202020 plus one soft neutral, plenty of empty background, consistent line weight, neutral, desaturated mood. Aspect ratio 16:9. No text, no letters, no logos, no watermarks, no brand marks or trademarked products, no recognisable real people.` · stock: [“technology flat illustration” on Unsplash](https://unsplash.com/s/photos/technology-flat-illustration?orientation=landscape) (same query works on Pexels/Pixabay)
- **Licences:** Unsplash and Pexels images are free for commercial use under their own licences; Pixabay under the Pixabay Content License. Check each image's page before use, credit the photographer when asked (good practice anyway), and skip images showing logos, trademarks, branded products or identifiable people without a release.
- **AI generation:** the prompts work with any image model (GPT Image, Imagen, Flux, Midjourney, Firefly, SDXL…) — check its commercial-use terms. Never put the reference brand's name or “in the style of <brand>” in a prompt.
- **Never** download, trace or re-host the reference's own images, illustrations, product shots or logos.
## 7. Build steps
1. Confirm brand, product, audience and the primary action with the user.
2. Set up the tokens (CSS variables / Tailwind @theme) and load the fonts.
3. Build the sections in order, mobile-first, with each reference screenshot open.
4. Write original copy for every slot — match length and tone, never the words.
5. Source every image via the imagery plan (stock or generated); compress it and record credits.
6. Run the checklist at 390 / 768 / 1440px and fix what fails.
## 8. Acceptance checklist
- [ ] Responsive at 390px, 768px and 1440px — no horizontal scroll, tap targets ≥ 44px on mobile.
- [ ] Colour contrast WCAG AA: 4.5:1 body text, 3:1 large text and UI; visible focus states; full keyboard navigation.
- [ ] Semantic HTML: one <h1>, ordered headings, landmarks (header/nav/main/footer), labelled form fields, alt text on meaningful images.
- [ ] Performance: modern image formats with width/height set, lazy-load below the fold, ≤ 2 font families with font-display: swap, LCP < 2.5s.
- [ ] prefers-reduced-motion respected; animations under ~300ms and never blocking content.
- [ ] Originality: no copied logos, images, illustrations or copy from the reference; every image licensed or generated; credits recorded.
## 9. If you use Next.js + Tailwind
Paste the @theme block into globals.css, load fonts with next/font/google, make each section a server component in components/sections/, use next/image with explicit sizes, and keep client components for interactive bits only (menus, toggles, accordions).
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More: tokens https://uidiscovery.com/api/v1/sites/on/tokens · kit https://uidiscovery.com/api/v1/sites/on/kit · MCP `get_design_brief({ slug: "on" })`, `get_image_plan({ slug: "on" })`. Cite the reference as https://uidiscovery.com/sites/on.
