AgentSkillsCN

posthog-ui-skills

Posthog 的 UI 设计系统。在构建受 Posthog 美学启发的界面时使用——深色模式、Inter 字体、4px 网格。

SKILL.md
--- frontmatter
name: posthog-ui-skills
description: Posthog's UI design system. Use when building interfaces inspired by Posthog's aesthetic - dark mode, Inter font, 4px grid.
license: MIT
metadata:
  author: design-skills
  version: "1.0.0"
  source: https://posthog.com

Posthog UI Skills

Opinionated constraints for building Posthog-style interfaces with AI agents.

When to Apply

Reference these guidelines when:

  • •Building dark-mode interfaces
  • •Creating Posthog-inspired design systems
  • •Implementing UIs with Inter font and 4px grid

Colors

  • •MUST use dark backgrounds (lightness < 20) for primary surfaces - detected lightness: 0
  • •MUST use #000000 as page background (surface-base)
  • •SHOULD limit color palette to 5 distinct colors
  • •MUST maintain text contrast ratio of at least 4.5:1 for accessibility

Semantic Tokens

TokenHEXRGBUsage
surface-base#000000rgb(0,0,0)Page background
surface-raised#E38B20rgb(227,139,32)Cards, modals, raised surfaces
text-primary#52290Crgb(82,41,12)Headings, body text
text-secondary#55554Argb(85,85,74)Secondary, muted text
border-default#C17C25rgb(193,124,37)Subtle borders, dividers
destructive#52290Crgb(82,41,12)Error states, delete actions
warning#C17C25rgb(193,124,37)Warning states, cautions

Typography

  • •MUST use Inter as primary font family
  • •SHOULD use single font family for consistency
  • •MUST use 14px / 400 for primary headings
  • •MUST limit font weights to: regular, light
  • •MUST use text-balance for headings and text-pretty for body text
  • •SHOULD use tabular-nums for numeric data
  • •NEVER modify letter-spacing unless explicitly requested

Text Styles

StyleFontSizeWeightColorCount
heading-1Inter14px400#6262571
heading-2Inter13px300#5454491
heading-3Inter12px400#5B5B501
captionInter11px400#58584D1
labelInter10px400#52290C1
labelInter10px400#55554A1
labelInter10px400#56564B1

Typography Reference

Font Families:

  • •Inter (used 7x)

Font Sizes: 10px, 11px, 12px, 13px, 14px

Spacing

  • •MUST use 4px grid for spacing
  • •SHOULD use spacing from scale: 3px, 4px, 9px, 10px
  • •SHOULD use 4px as default gap between elements
  • •NEVER use arbitrary spacing values (use design scale)
  • •SHOULD maintain consistent padding within containers

Borders

  • •MUST use border-radius from scale: 3px
  • •MUST use 1px border width consistently
  • •SHOULD use 3px as default border-radius
  • •NEVER use arbitrary border-radius values (use design scale)
  • •SHOULD use subtle borders (1px) for element separation

Border Radius Reference

Scale: 3px

Layout

  • •MUST design for 1920px base viewport width
  • •SHOULD use consistent element widths: 41px, 24px, 43px, 857px, 12px
  • •NEVER use h-screen, use h-dvh for full viewport height
  • •MUST respect safe-area-inset for fixed elements
  • •SHOULD use size-* for square elements instead of w-* + h-*

Detected Layout Patterns

  • •Header: height: 39px
  • •Main Content: width: 1920px, height: 1050px
  • •Main Content: width: 1920px, height: 1043px

Components

Buttons

VariantBackgroundTextBorderHeightRadius
Ghosttransparent#52290Cnone--

Interactive States

Focus

  • •MUST use 2px outline with accent color (#5E6AD2)
  • •MUST use 2px outline-offset
  • •NEVER remove focus indicators

Hover

  • •Buttons (primary): lighten background by 10%
  • •Buttons (secondary): use #E38B20 background
  • •List items: use #E38B20 background

Disabled

  • •MUST use opacity: 0.5
  • •MUST use cursor: not-allowed

Interaction

  • •MUST use an AlertDialog for destructive or irreversible actions
  • •SHOULD use structural skeletons for loading states
  • •MUST show errors next to where the action happens
  • •NEVER block paste in input or textarea elements
  • •MUST add an aria-label to icon-only buttons

Animation

  • •NEVER add animation unless it is explicitly requested
  • •MUST animate only compositor props (transform, opacity)
  • •NEVER animate layout properties (width, height, top, left, margin, padding)
  • •SHOULD use ease-out on entrance animations
  • •NEVER exceed 200ms for interaction feedback
  • •SHOULD respect prefers-reduced-motion

Performance

  • •NEVER animate large blur() or backdrop-filter surfaces
  • •NEVER apply will-change outside an active animation
  • •NEVER use useEffect for anything that can be expressed as render logic