Segment UI Skills

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

When to Apply

Reference these guidelines when:

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

Colors

• SHOULD use light backgrounds for primary surfaces
• MUST use #0748D8 as page background (surface-base)
• MUST use #94C2F0 for primary actions and focus states (accent)
• SHOULD reduce color palette (currently 14 colors detected)
• MUST maintain text contrast ratio of at least 4.5:1 for accessibility

Semantic Tokens

Token	HEX	RGB	Usage
surface-base	#0748D8	rgb(7,72,216)	Page background
surface-raised	#000000	rgb(0,0,0)	Cards, modals, raised surfaces
surface-overlay	#0F1423	rgb(15,20,35)	Overlays, tooltips, dropdowns
text-primary	#2F3239	rgb(47,50,57)	Headings, body text
text-2	#424856	rgb(66,72,86)	Additional text
text-secondary	#94C2F0	rgb(148,194,240)	Secondary, muted text
border-default	#1148C1	rgb(17,72,193)	Subtle borders, dividers
accent	#94C2F0	rgb(148,194,240)	Primary actions, links, focus

Typography

• MUST use Inter as primary font family
• SHOULD use single font family for consistency
• MUST use 50px / 700 for primary headings
• MUST use 31px / 500 for body text
• SHOULD reduce font weights (currently 5 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	50px	700	#E1E4E6	1
heading-2	Inter	46px	semi_bold	#2F3239	1
heading-3	Inter	46px	700	#222730	1
body	Inter	31px	500	#2D2C41	1
text-21px	Inter	21px	400	#B1B7C2	1
text-18px	Inter	18px	400	#54575E	1
text-16px	Inter	16px	300	#87A1D0	1
text-15px	Inter	15px	400	#5F6165	1
text-15px	Inter	15px	400	#484A50	1
text-15px	Inter	15px	400	#52545B	1

Typography Reference

Font Families:

• Inter (used 20x)

Font Sizes: 5px, 10px, 13px, 14px, 15px, 16px, 18px, 21px, 31px, 46px, 50px

Spacing

• MUST use 4px grid for spacing
• SHOULD use spacing from scale: 1px, 2px, 3px, 4px, 5px, 16px, 18px, 78px
• SHOULD use 2px 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: 6px, 7px
• MUST use 1px border width consistently
• SHOULD use 6px 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: 6px, 7px

Layout

• MUST design for 1920px base viewport width
• SHOULD use consistent element widths: 8px, 248px, 11px, 476px, 96px
• 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: 1920px, height: 545px
• Main Content: width: 1920px, height: 543px
• Header: height: 44px
• Header: height: 55px
• Header: height: 53px

Components

Buttons

Variant	Background	Text	Border	Height	Radius
Ghost	transparent	#94C2F0	none	-	-

Interactive States

Focus

• MUST use 2px outline with accent color (#94C2F0)
• MUST use 2px outline-offset
• NEVER remove focus indicators

Hover

• Buttons (primary): lighten background by 10%
• Buttons (secondary): use #000000 background
• List items: use #000000 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