amplitude-ui-skills

name	amplitude-ui-skills
description	Amplitude's UI design system. Use when building interfaces inspired by Amplitude's aesthetic - light mode, Inter font, 4px grid.
license	MIT
metadata	{"author":"design-skills","version":"1.0.0","source":"https://amplitude.com"}

Amplitude UI Skills

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

When to Apply

Reference these guidelines when:

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

Colors

• SHOULD use light backgrounds for primary surfaces
• MUST use #000000 as page background (surface-base)
• MUST use #3151E1 for primary actions and focus states (accent)
• SHOULD reduce color palette (currently 25 colors detected)
• MUST maintain text contrast ratio of at least 4.5:1 for accessibility

Semantic Tokens

Token	HEX	RGB	Usage
surface-base	#000000	rgb(0,0,0)	Page background
surface-raised	#FFFFFF	rgb(255,255,255)	Cards, modals, raised surfaces
surface-overlay	#EFF0F4	rgb(239,240,244)	Overlays, tooltips, dropdowns
text-primary	#171717	rgb(23,23,23)	Headings, body text
text-2	#383838	rgb(56,56,56)	Additional text
text-secondary	#BBBBBB	rgb(187,187,187)	Secondary, muted text
border-default	#3A3A3A	rgb(58,58,58)	Subtle borders, dividers
accent	#3151E1	rgb(49,81,225)	Primary actions, links, focus

Typography

• MUST use Inter as primary font family
• SHOULD use single font family for consistency
• MUST use 58px / 700 for primary headings
• MUST use 23px / 500 for body text
• SHOULD reduce font weights (currently 4 detected)
• 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

Style	Font	Size	Weight	Color	Count
heading-1	Inter	58px	700	#1D46E1	1
heading-2	Inter	56px	700	#161616	1
text-40px	Inter	40px	700	#171717	1
body	Inter	23px	500	#282828	1
text-19px	Inter	19px	400	#656565	1
text-16px	Inter	16px	400	#383838	1
text-14px	Inter	14px	400	#474747	1
text-14px	Inter	14px	400	#3E3E3E	1
text-13px	Inter	13px	400	#BBBBBB	1
text-13px	Inter	13px	400	#575757	1

Typography Reference

Font Families:

• Inter (used 51x)

Font Sizes: 5px, 6px, 7px, 8px, 9px, 10px, 11px, 13px, 14px, 16px, 19px, 23px, 40px, 56px, 58px

Spacing

• MUST use 4px grid for spacing
• SHOULD use spacing from scale: 1px, 2px, 3px, 4px, 5px, 6px, 7px, 11px
• 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: 1px, 2px, 3px, 5px, 6px, 12px, 18px, 25px
• SHOULD use 25px+ radius for pill-shaped elements
• SHOULD limit border widths to: 1px, 2px, 4px
• SHOULD use 25px 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: 1px, 2px, 3px, 5px, 6px, 12px, 18px, 25px

Layout

• MUST design for 1920px base viewport width
• SHOULD use consistent element widths: 118px, 17px, 135px, 14px, 9px
• SHOULD maintain text-heavy layout with clear hierarchy
• 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

• Main Content: width: 1465px, height: 988px

Components

Buttons

Variant	Background	Text	Border	Height	Radius
Ghost	transparent	#383838	none	-	-

Interactive States

Focus

• MUST use 2px outline with accent color (#3151E1)
• MUST use 2px outline-offset
• NEVER remove focus indicators

Hover

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