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