flowmanceStartub Design System
Startub is a dark, high-voltage startup site. Everything sits on pure black, ruled by faint vertical lines of blue light, and one colour does all the talking: electric #0000FF on the button, on one word of the hero and on giant stat numbers. Type is white Inter Tight 600, with grey tails on the leads and section titles.
Four signatures make it recognisable:
- Vertical light lines. A 16-column grid of 1px lines runs behind the whole page, each a gradient from black to #0000FF to black (linear-gradient(#000 10–30%, #0000FF 50%, #000 70–90%)), so thin blue glints appear down the columns.
- One blue word. The hero headline is white, with one phrase in #0000FF set on its own indented line: Develop / cutting-edge / tech websites.
- Grey tails. Leads and section titles end in #999999: Kickstart your startup's success with the Startub Webflow template.
- Giant blue stats. 99%, 48, 6.5 at 120px weight 600 in #0000FF, fading darker toward the bottom, over grey labels.
The Startub. wordmark ends in a blue full stop.
Colors
Surfaces
#000000Page background, menu panels, footer
#111111Start of the tab panel gradient (linear-gradient(36deg, #111111, #00000026))
#222222Inactive tab pills (.tab-inline-block), submit text
#81818B · 20%Subscribe field and its button well
#FFFFFFSend Message submit and the square arrow button
Ink
#FFFFFFText on blue
#FFFFFFHeadlines, nav, names, active labels
#999999Paragraphs (--grey), grey tails, Learn More links, stat labels, footer links
#FFFFFFQuotes and names over testimonial photos
#222222Text on inverse-canvas
Action
#0000FF--blue-main: the pill button, active tab, hero accent word, stats, icons, nav counters, the line glow
#0000FFLines & effects
#FFFFFF · 15%1px rule on the contact form
#000000 · 50%Round slider arrows over photos
Typography
Inter Tight · display-stat
The quick brown fox jumps99%, 48, 6.5 in blue. 120px · 600 · 0.9
Inter Tight · headline-lg
The quick brown fox jumpsSection titles with grey tails (Tailored for teams, big and small.). 44px · 600 · 1.3
Inter Tight · title-xl
The quick brown fox jumpsBlue headings inside tab panels (.medium-heading). 30px · 600 · 1.2
Inter Tight · body-lead
The quick brown fox jumpsLeads, tab panel text with grey tails. 26px · 600 · 1.4
Inter Tight · label-lg
The quick brown fox jumpsButton label, Menu, stat labels, footer titles. 18px · 600 · 1.11
Inter Tight · micro
The quick brown fox jumpsNumbers in the 33px blue menu counters. 13px · 600 · 1.54
Spacing & shape
| Purpose | Value |
|---|---|
| Container | max 1200px, centred; sections add 5% side padding (72px at 1440px) |
| Section rhythm | .section is padding: 120px 5% (80px top and bottom at ≤991px, 60px at ≤479px); the CTA uses 100px (80px at ≤991px, 50px at ≤767px); the footer 60px 5% 30px (50px top at ≤479px) |
| Breakpoints | 991px, 767px and 479px, plus a 1440px+ step |
Spacing scale
| Token | Value | Preview |
|---|---|---|
xs | 10px | |
sm | 15px | |
md | 30px | |
lg | 40px | |
xl | 80px | |
2xl | 100px | |
3xl | 150px |
Layout spacing
| Token | Value | Preview |
|---|---|---|
column-gap | 16px | |
nav-y | 25px | |
section-x | 72px | |
section-cta | 100px | |
section | 120px |
Border radius
Surfaces
How the surfaces stack, from the page background up. Hex codes and roles are in Colors above.
Motion
| Fade in | opacity 0 → 1, 1000ms outQuart on scroll into view |
| Button hover | Label rolls up; arrow slides from y 100px to centre; about 300ms |
| Menu open | Two half panels grow from width 0%, 300–500ms ease; links fade in 300ms ease; burger lines rotate 200ms easeInOut |
| Menu link roll | Label moves up out of the 74px mask and a copy rolls in, about 400ms ease |
| Mouse parallax | Hero shapes move ±10px, and larger layers ±80px, on mouse move, 500ms |
| Icon and image hover | Filter change, 300ms ease |
| Link hover | Colour, border and padding, 300ms (transition: all .3s) |
| Subscribe arrow | Background 200ms cubic-bezier(0.645, 0.045, 0.355, 1), opacity 0.8 on hover |
Do’s and don’ts
- Keep the canvas pure #000000 with the faint vertical blue light lines behind content.
- Put one word or phrase of the hero headline in primary #0000FF, on its own line; other headlines use grey tails instead.
- End leads and titles in ink-muted #999999 at the same size and weight 600.
- Use the #0000FF pill (40px radius, 70px tall, padding 25px 45px) for the single main action.
- Show numbers huge: 120px weight 600 in #0000FF over #999999 labels.
- Use blue line icons and glossy blue 3D shapes for illustration.
- Add a second accent colour or any of the unused CSS colours.
- Put #999999 text on #222222 below 17px; keep grey on black.
- Use white at an alpha for body text; muted text is #999999.
- Add drop shadows, borders around cards, or bright card fills; panels stay within #000000–#111111.
- Use #0000FF text below 30px or for paragraphs: on #000000 it is only about 2.4:1, so blue text stays at 30px+ weight 600 (hero word, tab headings, stats).
- Use uppercase or letter spacing.
Example prompt
Any page in the Startub style
More design systems like this
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Get All AccessUpgrade to All AccessHow to use the Startub design system
Pick a file to see what it’s for and where it goes.
What it is
The whole design system in one markdown file, written for AI: every color, type style, spacing value, component and motion rule, plus do's, don'ts and a ready prompt.
Best for
Claude, ChatGPT, Gemini, Cursor and v0, or any other AI tool that builds pages or code.
How to use it
- Put
DESIGN.mdin your project and mention it in your request, or save it as.cursor/rules/startub.mdc - For the rule file, start it with a front-matter block that sets
alwaysApply: true, so every chat uses it - Ask: “Build a pricing page using DESIGN.md.” Cursor follows the colors, fonts, spacing and rules
- Put
DESIGN.mdin the project root - Add one line to
CLAUDE.md: “Follow DESIGN.md for all UI.” - Ask for any page or component; Claude reads the file first
- Attach
DESIGN.mdto the chat (or paste it in) - Ask: “Build a landing page in this design system.”
- Keep the file in the chat or project knowledge, so follow-up pages stay on style
What it is
Every token as data, in the W3C Design Tokens format: colors with their roles, type styles, radius, spacing, and component tokens that point at them.
Best for
Figma (Tokens Studio), Style Dictionary and other design-token tools, and build scripts.
How to use it
- In Figma, open Tokens Studio, choose Import, and pick
tokens.json - Or point Style Dictionary’s
sourceat it to generate tokens for any platform - In code, import it like any JSON file
What it is
A Tailwind CSS v4 theme: every color, font, type style, radius and spacing value becomes a Tailwind utility, like bg-canvas, text-headline-lg or rounded-md.
Best for
Tailwind v4 projects, and AI builders that write Tailwind (v0, Lovable, Bolt).
How to use it
- Save
theme.cssnext to your main CSS file - Import it after Tailwind:
@import "tailwindcss"; @import "./theme.css"; - Use the classes:
bg-canvas text-ink rounded-md p-lg
What it is
The same tokens as plain CSS variables on :root. Component values point at the color variables, so changing one color updates everything that uses it.
Best for
Any website: plain CSS, Webflow custom code, Framer, WordPress.
How to use it
- Add it to your stylesheet, or in Webflow paste it into Site settings → Custom code inside a
<style>tag - Use the variables anywhere:
color: var(--color-ink) - Change a token once and every place that uses it follows