Spline design specDesign

A pure-black 3D tool brand that is near-monochrome by design: the live WebGL scene supplies every colour while the interface is built entirely from a published white-alpha ladder rather than hex greys, with frosted backdrop-blur panels standing in for elevation — there are no box-shadows and no CSS gradients anywhere — one Spline Sans held at 400-500 with normal tracking even at 58px, and a single saturated blue reserved for the one primary CTA.

Browse Spline in the interactive gallery

Captured from the live site's computed styles into a prompt-ready DESIGN.md you can paste into Cursor, v0, Lovable, Bolt or Claude Code. Below is a summary of each captured surface.

Marketing site

Source: spline.design (live DOM, computed styles + published CSS custom properties), 2026-07-19. Coverage: home / platform landing. Logged-in 3D editor not captured (needs login). Note: the surface is pure-black and near-monochrome, not the "vivid gradients" the category suggests — no CSS gradient was found anywhere on the page.

Visual Theme & Atmosphere

Spline puts a pure #000 canvas under live WebGL and lets the 3D scene supply every bit of colour — the UI itself is almost entirely white-at-varying-alpha. That is the defining idea: instead of hex greys, the whole interface is built from a published alpha ladder (#ffffff03 through #ffffffe6), so chrome floats translucently over whatever the scene is doing behind it. Buttons are frosted white-alpha pills, panels are rgba(255,255,255,.08) with blur(24px), and ambient depth comes from a blur(100px) bloom rather than shadows — there are no box-shadows on the page at all. One saturated blue #0062ff marks the single primary CTA. Spline Sans, held at 400/500, keeps the type quiet so the 3D work reads as the content. Feels: dark, weightless, cinematic, tool-like.

Color Palette & Roles

Core (published tokens)

TokenValueRole / usage
--color-bg#000Page canvas — pure black
--color-bg-transparent#1110Transparent black
--color-text-main#fffHeadlines, primary text
--color-text-navigation#ffffffb3 (70%)Nav links
--color-text-paragraph#fff9 (60%)Body copy
--color-white#fffBase for the whole alpha ladder

The white-alpha ladder (the system's real "greys")

TokenValue
--color-white-001#ffffff03
--color-white-003#ffffff08
--color-white-005#ffffff0d
--color-white-008#ffffff14
--color-white-010#ffffff1a
--color-white-020#fff3
--color-white-040#fff6
--color-white-060#fff9
--color-white-070#ffffffb3
--color-white-080#fffc
--color-white-090#ffffffe6

Surfaces

TokenValueRole / usage
--color-btn-bg#ffffff0dButton rest fill
--color-btn-bg-highlight#ffffff0fButton highlight
--color-panel-bgrgba(255,255,255,.08)Floating panel
--color-panel-bg-hoverrgba(255,255,255,calc(.08 + .03))Panel hover (computed step)
--color-menu-dropdown#1e1e23ccDropdown surface (the one non-white tint)

Accent & product colours

TokenValueRole / usage
--color-blue#0062ffTHE primary CTA fill
--color-blue-lighter#5797ffHover / lighter blue
--color-blue-dark#217ce5Pressed / darker blue
--color-blue-ios#5966f3Alternate blue-violet
--color-purple-bright#a770ffAccent
--color-purple#8f66ff21Purple tint wash
--color-pink#ff5cabAccent
--color-red#fd585bError / accent
--color-yellow#ffb01fWarning / accent
--color-green-bright#47b35fSuccess
--color-green#49bc541aGreen tint wash
--color-bg-pink#ffe6e6Pale illustration ground
--color-bg-greenish#c1f6e8Pale illustration ground

Plan-tier colours

TokenValue
--color-free / -darkerrgba(255,255,255,.08) / calc(.08 + .03)
--color-super / -darker / -lighter#00a376 / #008761 / #38e2b3
--color-team / -darker / -lighter#915eff / #7448d4 / #d680ff

Rules. Chrome is built from the white-alpha ladder, never from hex greys — this is what lets it float over live 3D. Blue #0062ff is the only saturated fill in the interface; every other hue (purple, pink, red, yellow, green) is a product/plan or illustration colour, not chrome. Plan tiers are the one place a second saturated colour is allowed (super green, team purple).

Typography Rules

RoleSize/LineWeightTracking
Hero h158/72500normal
Section h236/44500normal (#ffffff at 90%)
Card h314/24500normal (#ffffff at 90%)
Banner h414/20500normal
Body / paragraph12/16400normal (#ffffff at 90%)
Nav link16400normal (#ffffffb3)
Button label16400 (500 on the nav fill)normal

Patterns: the weight ceiling is 500 and tracking is normal at every size — no negative tracking anywhere, which is unusual at a 58px display size and is part of why the type reads as neutral tool chrome rather than brand voice. Hierarchy is carried by size and by *alpha* (100% → 90% → 70% → 60%) rather than by colour or weight. Line-height stays generous on display (58/72). Sentence case throughout.

Also documented in the full DESIGN.md: Component Stylings, Layout Principles, Depth & Elevation, Motion, Backgrounds, Effects & WebGL, Do's and Don'ts, Responsive Behavior, Agent Prompt Guide.