Sitepeel
astro.build homepage as measured on October 21, 2026

DESIGN.md · measured October 21, 2026

Astro design system

Dark interface measured from astro.build: Obviously type with system-ui, dark indigo accents, tonal surfaces and pill-shaped controls.

Background
#060913
Primary
#1A1367
Type
Obviously
Corners
Pill
Download DESIGN.md

From astro.build ↗ · 409 elements at 1440×900 and 390×844 · Independent analysis, not affiliated with Astro

Astro colors

17 roles measured on the page, grouped by where each color is used.

Surfaces

Cool Charcoal#060913backgroundPage background · 3×
Cool Charcoal#0D0F14surface-container-lowRaised areas one step from the page · 3×
Cool Charcoal#0C0F19surface-containerCards and panels · 15×
Graphite 30%#2C2C2C4DoverlayTranslucent fill for cards and controls · 7×
Cool Charcoal 55%#0609138Coverlay-strongStronger translucent fill · 1×

Text

Cool Snow#F2F6FAon-surfacePrimary text and headings · 21×
White#FFFFFFon-surface-strong · --tw-ring-offset-colorHeadings and emphasis · 25×
Cool Silver#BFC1C9on-surface-variantSecondary text · 35×
Cool Gray#858B98on-surface-mutedMuted text and metadata · 11×
White#FFFFFFon-primaryText and icons on primary

Accents

Dark Indigo#1A1367primaryBrand color in logos and imagery
Dark Violet#5919A7secondaryBrand color in logos and imagery · 18×
Blue#54B9FFtertiaryMost used accent color · 15×

Borders

Cool Gray 20%#858B9833outlineBorders and dividers · 34×
Cool Gray 30%#858B984Doutline-variantSecondary dividers · 3×

Status

Teal#4BF3C8successSuccess and positive states · 12×
Light Orange#FFD493warningWarnings and highlights · 3×

Gradients

Astro fonts

2 families.

AaObviouslyWeights 400, 700Obviously, obviously-fallback, system-ui, sans-serif
Aasystem-uiWeights 300, 400ui-sans-serif, system-ui, sans-serif, Apple Color Emoji
headline-displayPage title (h1)Astro48px · 700 · 1.1
mobile 30px
headline-lgSection headings (h2)The quick brown fox jumps over the lazy dog30px · 400 · 1.2
mobile 24px
headline-mdSub-section headingsThe quick brown fox jumps over the lazy dog20px · 700 · 1.4
body-mdBody textThe quick brown fox jumps over the lazy dog16px · 300 · 1.5
body-smSecondary and small textThe quick brown fox jumps over the lazy dog14px · 400 · 1.81
label-mdButtons, navigation and labelsThe quick brown fox jumps over the lazy dog16px · 400 · 1.5

Contrast

Text on #060913

AaAAA18.3:1
AaAAA19.9:1
AaAAA11.1:1
AaAA5.8:1

Spacing

4px grid · 100% of values fit

xs4px
sm8px
md16px
lg32px
xl48px
gutter8px
margin32px
container1280px

Shapes

Corner radii, most used first.

full9999px · 68×
lg16px · 60×
sm8px · 44×
md12px · 20×

Depth

Shadow

Components

Rebuilt from the measured CSS.

Get Started
button-primaryFilled button · hover to see the measured hover state
Astro 7.4 Available now!
button-outlineOutlined button
React
button-ghostText button
your@email.com
input-fieldInput field
Card
cardCard
Inline link
linkInline link

Motion

Interface transitions

0.3s0.15s0.5s
cubic-bezier(0.4, 0, 0.2, 1)cubic-bezier(0, 0, 0.2, 1)

Do’s and don’ts

Rules written from the measurements, so a coding agent stays on style.

  • Use #060913 for the page and lift surfaces in small steps: #0D0F14, #0C0F19.
  • Keep text in 4 levels: #F2F6FA, #FFFFFF, #BFC1C9, #858B98.
  • Use #1A1367 as the brand accent: header, logo and key highlights.
  • Keep spacing on the 4px grid.
  • Make buttons and chips fully rounded (9999px); most other elements use 16px corners.
  • Introduce new font families beyond Obviously and system-ui.
  • Use #1A1367 for large backgrounds or body text.
  • Make interface transitions slower than 0.5s.
DESIGN.md217 lines

What you can build with it

Landing pages, pricing tables, dashboards: your AI coding agent builds them in this style, with these colors, fonts, spacing and buttons instead of its defaults.

Download DESIGN.md, put it in your project’s root folder, then ask your agent for a page.

Prompt · DESIGN.md attached

Build a landing page for my product. Follow for every color, font, spacing value, corner and button.

Need more than one page?

Design MD in the Sitepeel tools for Chrome measures pages behind a login, combines several pages into one file and works on any site you open.

Explore the tool

FAQ

Questions

What can I build with the Astro DESIGN.md?

Any page or component in this style: a landing page, pricing table, dashboard or sign-up form. Your AI coding agent uses the measured colors, Obviously type, spacing, corners and buttons instead of its own defaults.

How do I use it with Claude Code or Cursor?

Download the file and put it in your project’s root folder, then ask your agent to follow DESIGN.md. Step-by-step guides: Claude Code, Cursor, Codex, GitHub Copilot.

Is this Astro’s official design system?

No. Sitepeel measured it from astro.build’s public page on October 21, 2026. It is an independent analysis, not made or approved by Astro.

Can I use Astro’s style in my own product?

Use it to learn, prototype and compare. For a real product, make the style your own, and never copy Astro’s logo, name, pictures or text.

How accurate are the values?

Each value was measured on the rendered page after it fully loaded, on desktop and mobile: colors where they appear, type with tracking, spacing, corners, shadows and hover states. Sites change, so check the date at the top.