Design System Inspired by Sanity

1. Visual Theme & Atmosphere

Sanity's website is a developer-content platform rendered as a nocturnal command center -- dark, precise, and deeply structured. The entire experience sits on a near-black canvas (#0b0b0b) that reads less like a "dark mode toggle" and more like the natural state of a tool built for people who live in terminals. Where most CMS marketing pages reach for friendly pastels and soft illustration, Sanity leans into the gravity of its own product: structured content deserves a structured stage.

The signature typographic voice is waldenburgNormal -- a distinctive, slightly geometric sans-serif with tight negative letter-spacing (-0.32px to -4.48px at display sizes) that gives headlines a compressed, engineered quality. At 112px hero scale with -4.48px tracking, the type feels almost machined -- like precision-cut steel letterforms. This is paired with IBM Plex Mono for code and technical labels, creating a dual-register voice: editorial authority meets developer credibility.

What makes Sanity distinctive is the interplay between its monochromatic dark palette and vivid, saturated accent punctuation. The neutral scale runs from pure black through a tightly controlled gray ramp (#0b0b0b -> #212121 -> #353535 -> #797979 -> #b9b9b9 -> #ededed -> #ffffff) with no warm or cool bias -- just pure, achromatic precision. Against this disciplined backdrop, a neon green accent (display-p3 green) and electric blue (#0052ef) land with the impact of signal lights in a dark control room. The orange-red CTA (#f36458) provides the only warm touch in an otherwise cool system.

Key Characteristics:

• Near-black canvas (#0b0b0b) as the default, natural environment -- not a dark "mode" but the primary identity
• waldenburgNormal with extreme negative tracking at display sizes, creating a precision-engineered typographic voice
• Pure achromatic gray scale -- no warm or cool undertones, pure neutral discipline
• Vivid accent punctuation: neon green, electric blue (#0052ef), and coral-red (#f36458) against the dark field
• Pill-shaped primary buttons (99999px radius) contrasting with subtle rounded rectangles (3-6px) for secondary actions
• IBM Plex Mono as the technical counterweight to the editorial display face
• Full-bleed dark sections with content contained in measured max-width containers
• Hover states that shift to electric blue (#0052ef) across all interactive elements -- a consistent "activation" signal

2. Color Palette & Roles

Primary Brand

• Sanity Black (#0b0b0b): The primary canvas and dominant surface color. Not pure black but close enough to feel absolute. The foundation of the entire visual identity.
• Pure Black (#000000): Used for maximum-contrast moments, deep overlays, and certain border accents.
• Sanity Red (#f36458): The primary CTA and brand accent -- a warm coral-red that serves as the main call-to-action color. Used for "Get Started" buttons and primary conversion points.

Accent & Interactive

• Electric Blue (#0052ef): The universal hover/active state color across the entire system. Buttons, links, and interactive elements all shift to this blue on hover. Also used as --color-blue-700 for focus rings and active states.
• Light Blue (#55beff / #afe3ff): Secondary blue variants used for accent backgrounds, badges, and dimmed blue surfaces.
• Neon Green (color(display-p3 .270588 1 0)): A vivid, wide-gamut green used as --color-fg-accent-green for success states and premium feature highlights. Falls back to #19d600 in sRGB.
• Accent Magenta (color(display-p3 .960784 0 1)): A vivid wide-gamut magenta for specialized accent moments.

Surface & Background

• Near Black (#0b0b0b): Default page background and primary surface.
• Dark Gray (#212121): Elevated surface color for cards, secondary containers, input backgrounds, and subtle layering above the base canvas.
• Medium Dark (#353535): Tertiary surface and border color for creating depth between dark layers.
• Pure White (#ffffff): Used for inverted sections, light-on-dark text, and specific button surfaces.
• Light Gray (#ededed): Light surface for inverted/light sections and subtle background tints.

Neutrals & Text

• White (#ffffff): Primary text color on dark surfaces, maximum legibility.
• Silver (#b9b9b9): Secondary text, body copy on dark surfaces, muted descriptions, and placeholder text.
• Medium Gray (#797979): Tertiary text, metadata, timestamps, and de-emphasized content.
• Charcoal (#212121): Text on light/inverted surfaces.
• Near Black Text (#0b0b0b): Primary text on white/light button surfaces.

Semantic

• Error Red (#dd0000): Destructive actions, validation errors, and critical warnings -- a pure, high-saturation red.
• GPC Green (#37cd84): Privacy/compliance indicator green.
• Focus Ring Blue (#0052ef): Focus ring color for accessibility, matching the interactive blue.

Border System

• Dark Border (#0b0b0b): Primary border on dark containers -- barely visible, maintaining minimal containment.
• Subtle Border (#212121): Standard border for inputs, textareas, and card edges on dark surfaces.
• Medium Border (#353535): More visible borders for emphasized containment and dividers.
• Light Border (#ffffff): Border on inverted/light elements or buttons needing contrast separation.
• Orange Border (color(display-p3 1 0.3333 0)): Special accent border for highlighted/featured elements.

3. Typography Rules

Font Family

• Display / Headline: waldenburgNormal, fallback: waldenburgNormal Fallback, ui-sans-serif, system-ui
• Body / UI: waldenburgNormal, fallback: waldenburgNormal Fallback, ui-sans-serif, system-ui
• Code / Technical: IBM Plex Mono, fallback: ibmPlexMono Fallback, ui-monospace
• Fallback / CJK: Helvetica, fallback: Arial, Hiragino Sans GB, STXihei, Microsoft YaHei, WenQuanYi Micro Hei

Note: waldenburgNormal is a custom typeface. For external implementations, use Inter or Space Grotesk as the sans substitute (geometric, slightly condensed feel). IBM Plex Mono is available on Google Fonts.

Hierarchy

Principles

• Extreme negative tracking at scale: Display headings at 72px+ use aggressive negative letter-spacing (-2.88px to -4.48px), creating a tight, engineered quality that distinguishes Sanity from looser editorial typography.
• Single font, multiple registers: waldenburgNormal handles both editorial display and functional UI text. The weight range is narrow (400-425 for most, 500-600 only for tiny labels), keeping the voice consistent.
• OpenType feature control: Typography uses deliberate feature settings including "cv01", "cv11", "cv12", "cv13", "ss07" for display sizes and "calt" 0 for body text, fine-tuning character alternates for different contexts.
• Tight headings, relaxed body: Headings use 1.00-1.24 line-height (extremely tight), while body text breathes at 1.50. This contrast creates clear visual hierarchy.
• Uppercase for technical labels: IBM Plex Mono captions and small labels frequently use text-transform: uppercase with tight line-heights, creating a "system readout" aesthetic for technical metadata.

4. Component Stylings

Buttons

Primary CTA (Pill)

• Background: Sanity Red (#f36458)
• Text: White (#ffffff)
• Padding: 8px 16px
• Border Radius: 99999px (full pill)
• Border: none
• Hover: Electric Blue (#0052ef) background, white text
• Font: 16px waldenburgNormal, weight 400

Secondary (Dark Pill)

• Background: Near Black (#0b0b0b)
• Text: Silver (#b9b9b9)
• Padding: 8px 12px
• Border Radius: 99999px (full pill)
• Border: none
• Hover: Electric Blue (#0052ef) background, white text

Outlined (Light Pill)

• Background: White (#ffffff)
• Text: Near Black (#0b0b0b)
• Padding: 8px
• Border Radius: 99999px (full pill)
• Border: 1px solid #0b0b0b
• Hover: Electric Blue (#0052ef) background, white text

Ghost / Subtle

• Background: Dark Gray (#212121)
• Text: Silver (#b9b9b9)
• Padding: 0px 12px
• Border Radius: 5px
• Border: 1px solid #212121
• Hover: Electric Blue (#0052ef) background, white text

Uppercase Label Button

• Font: 11px waldenburgNormal, weight 600, uppercase
• Background: transparent or #212121
• Text: Silver (#b9b9b9)
• Letter-spacing: normal
• Used for tab-like navigation and filter controls

Cards

Dark Content Card

• Background: #212121
• Border: 1px solid #353535 or #212121
• Border Radius: 6px
• Padding: 24px
• Text: White (#ffffff) for titles, Silver (#b9b9b9) for body
• Hover: subtle border color shift or elevation change

Feature Card (Full-bleed)

• Background: #0b0b0b or full-bleed image/gradient
• Border: none or 1px solid #212121
• Border Radius: 12px
• Padding: 32-48px
• Contains large imagery with overlaid text

Inputs

Text Input / Textarea

• Background: Near Black (#0b0b0b)
• Text: Silver (#b9b9b9)
• Border: 1px solid #212121
• Padding: 8px 12px
• Border Radius: 3px
• Focus: outline with var(--focus-ring-color) (blue), 2px solid
• Focus background: shifts to deep cyan (#072227)

Search Input

• Background: #0b0b0b
• Text: Silver (#b9b9b9)
• Padding: 0px 12px
• Border Radius: 3px
• Placeholder: Medium Gray (#797979)

Navigation

Top Navigation

• Background: Near Black (#0b0b0b) with backdrop blur
• Height: auto, compact padding
• Logo: left-aligned, Sanity wordmark
• Links: waldenburgNormal 16px, Silver (#b9b9b9)
• Link Hover: Electric Blue via --color-fg-accent-blue
• CTA Button: Sanity Red pill button right-aligned
• Separator: 1px border-bottom #212121

Footer

• Background: Near Black (#0b0b0b)
• Multi-column link layout
• Links: Silver (#b9b9b9), hover to blue
• Section headers: White (#ffffff), 13px uppercase IBM Plex Mono

Badges / Pills

Neutral Subtle

• Background: White (#ffffff)
• Text: Near Black (#0b0b0b)
• Padding: 8px
• Font: 13px
• Border Radius: 99999px

Neutral Filled

• Background: Near Black (#0b0b0b)
• Text: White (#ffffff)
• Padding: 8px
• Font: 13px
• Border Radius: 99999px

5. Layout Principles

Spacing System

Base unit: 8px

Grid & Container

• Max content width: ~1440px (inferred from breakpoints)
• Page gutter: 32px on desktop, 16px on mobile
• Content sections use full-bleed backgrounds with centered, max-width content
• Multi-column layouts: 2-3 columns on desktop, single column on mobile
• Card grids: CSS Grid with consistent gaps (16-24px)

Whitespace Philosophy

Sanity uses aggressive vertical spacing between sections (64-120px) to create breathing room on the dark canvas. Within sections, spacing is tighter (16-32px), creating dense information clusters separated by generous voids. This rhythm gives the page a "slides" quality -- each section feels like its own focused frame.

Border Radius Scale

6. Depth & Elevation

Shadow System

Depth Philosophy

Sanity's depth system is almost entirely colorimetric rather than shadow-based. Elevation is communicated through surface color shifts: #0b0b0b (ground) -> #212121 (elevated) -> #353535 (prominent) -> #ffffff (inverted/highest). This approach is native to dark interfaces where traditional drop shadows would be invisible. The few shadows that exist are ring-based (0px 0px 0px Npx) or blur-based (backdrop-filter) rather than offset shadows, maintaining the flat, precision-engineered aesthetic.

Border-based containment (1px solid #212121 or #353535) serves as the primary spatial separator, with the border darkness calibrated to be visible but not dominant. The system avoids "floating card" aesthetics -- everything feels mounted to the surface rather than hovering above it.

7. Do's and Don'ts

Do

• Use the achromatic gray scale as the foundation -- maintain pure neutral discipline with no warm/cool tinting
• Apply Electric Blue (#0052ef) consistently as the universal hover/active state across all interactive elements
• Use extreme negative letter-spacing (-2px to -4.48px) on display headings 48px and above
• Keep primary CTAs as full-pill shapes (99999px radius) with the coral-red (#f36458)
• Use IBM Plex Mono uppercase for technical labels, tags, and system metadata
• Communicate depth through surface color (dark-to-light) rather than shadows
• Maintain generous vertical section spacing (64-120px) on the dark canvas
• Use "cv01", "cv11", "cv12", "cv13", "ss07" OpenType features for display typography

Don't

• Don't introduce warm or cool color tints to the neutral scale -- Sanity's grays are pure achromatic
• Don't use drop shadows for elevation -- dark interfaces demand colorimetric depth
• Don't apply border-radius between 13px and 99998px -- the system jumps from 12px (large card) directly to pill (99999px)
• Don't mix the coral-red CTA with the electric blue interactive color in the same element
• Don't use heavy font weights (700+) -- the system maxes out at 600 and only for 11px uppercase labels
• Don't place light text on light surfaces or dark text on dark surfaces without checking the gray-on-gray contrast ratio
• Don't use traditional offset box-shadows -- ring shadows (0 0 0 Npx) or border-based containment only
• Don't break the tight line-height on headings -- 1.00-1.24 is the range, never go to 1.5+ for display text

8. Responsive Behavior

Breakpoints

Collapsing Strategy

• Navigation: Horizontal links collapse to hamburger menu below 768px
• Hero typography: Scales from 112px -> 72px -> 48px -> 38px across breakpoints, maintaining tight letter-spacing ratios
• Grid layouts: 3-column -> 2-column at ~960px, single-column below 768px
• Card grids: Horizontal scrolling on mobile instead of wrapping (preserving card aspect ratios)
• Section spacing: Vertical padding reduces by ~40% on mobile (120px -> 64px -> 48px)
• Button sizing: CTA pills maintain padding but reduce font size; ghost buttons stay fixed
• Code blocks: Horizontal scroll with preserved monospace formatting

Mobile-Specific Adjustments

• Full-bleed sections extend edge-to-edge with 16px internal gutters
• Touch targets: minimum 44px for all interactive elements
• Heading letter-spacing relaxes slightly at mobile sizes (less aggressive negative tracking)
• Image containers switch from fixed aspect ratios to full-width with auto height

9. Agent Prompt Guide

Quick Color Reference

Background:      #0b0b0b (near-black canvas)
Surface:         #212121 (elevated cards/containers)
Border:          #353535 (visible) / #212121 (subtle)
Text Primary:    #ffffff (white on dark)
Text Secondary:  #b9b9b9 (silver on dark)
Text Tertiary:   #797979 (medium gray)
CTA:             #f36458 (coral-red)
Interactive:     #0052ef (electric blue, all hovers)
Success:         #19d600 (green, sRGB fallback)
Error:           #dd0000 (pure red)
Light Surface:   #ededed / #ffffff (inverted sections)

Example Prompts

Landing page section: "Create a feature section with a near-black (#0b0b0b) background. Use a 48px heading in Inter with -1.68px letter-spacing, white text. Below it, 16px body text in #b9b9b9 with 1.50 line-height. Include a coral-red (#f36458) pill button with white text and a secondary dark (#0b0b0b) pill button with #b9b9b9 text. Both buttons hover to #0052ef blue."

Card grid: "Build a 3-column card grid on a #0b0b0b background. Each card has a #212121 surface, 1px solid #353535 border, 6px border-radius, and 24px padding. Card titles are 24px white with -0.24px letter-spacing. Body text is 13px #b9b9b9. Add a 13px IBM Plex Mono uppercase tag in #797979 at the top of each card."

Form section: "Design a contact form on a #0b0b0b background. Inputs have #0b0b0b background, 1px solid #212121 border, 3px border-radius, 8px 12px padding, and #b9b9b9 placeholder text. Focus state shows a 2px blue (#0052ef) ring. Submit button is a full-width coral-red (#f36458) pill. Include a 13px #797979 helper text below each field."

Navigation bar: "Create a sticky top navigation on #0b0b0b with backdrop blur. Left: brand text in 15px white. Center/right: nav links in 16px #b9b9b9 that hover to blue. Far right: a coral-red (#f36458) pill CTA button. Bottom border: 1px solid #212121."

Iteration Guide

1. Start dark: Begin with #0b0b0b background, #ffffff primary text, #b9b9b9 secondary text
2. Add structure: Use #212121 surfaces and #353535 borders for containment -- no shadows
3. Apply typography: Inter (or Space Grotesk) with tight letter-spacing on headings, 1.50 line-height on body
4. Color punctuation: Add #f36458 for CTAs and #0052ef for all hover/interactive states
5. Refine spacing: 8px base unit, 24-32px within sections, 64-120px between sections
6. Technical details: Add IBM Plex Mono uppercase labels for tags and metadata
7. Polish: Ensure all interactive elements hover to #0052ef, all buttons are pills or subtle 5px radius, borders are hairline (1px)