Apple UI Skills

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

When to Apply

Reference these guidelines when:

• Building light-mode interfaces

• Creating Apple-inspired design systems

• Implementing UIs with Inter font and 4px grid

Colors

• SHOULD use light backgrounds for primary surfaces

• MUST use #FFFFFF as page background (surface-base )

• MUST use #155BD0 for primary actions and focus states (accent )

• SHOULD limit color palette to 10 distinct colors

• MUST maintain text contrast ratio of at least 4.5:1 for accessibility

Semantic Tokens

Token HEX RGB Usage

surface-base

#FFFFFF rgb(255,255,255) Page background

surface-raised

#0858DC rgb(8,88,220) Cards, modals, raised surfaces

text-primary

#808080 rgb(128,128,128) Headings, body text

text-secondary

#6D89B5 rgb(109,137,181) Secondary, muted text

text-tertiary

#90C5F1 rgb(144,197,241) Additional text

border-default

#B5C7D8 rgb(181,199,216) Subtle borders, dividers

accent

#155BD0 rgb(21,91,208) Primary actions, links, focus

Typography

• MUST use Inter as primary font family

• SHOULD use single font family for consistency

• MUST use 51px / 700 for primary headings

• MUST use 27px / 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 51px 700 #2D2B30 1

text-43px

Inter 43px 700 #272729 1

body

Inter 27px 500 #454547 1

body-secondary

Inter 26px 500 #3D3C41 1

text-16px

Inter 16px 400 #6D89B5 1

text-15px

Inter 15px 400 #8EC7F2 1

text-14px

Inter 14px 400 #90C5F1 1

text-12px

Inter 12px 300 #808080 1

caption

Inter 11px 300 #707070 1

label

Inter 10px 400 #7E7E7E 1

Typography Reference

Font Families:

• Inter (used 18x)

Font Sizes: 9px, 10px, 11px, 12px, 14px, 15px, 16px, 26px, 27px, 43px, 51px

Spacing

• MUST use 4px grid for spacing

• SHOULD use spacing from scale: 2px, 4px, 13px, 34px

• 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: 21px

• SHOULD use 21px+ radius for pill-shaped elements

• MUST use 1px border width consistently

• SHOULD use 21px 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: 21px

Layout

• MUST design for 1920px base viewport width

• SHOULD use consistent element widths: 46px, 50px, 36px, 47px, 32px

• 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: 43px

• Main Content: width: 1920px, height: 694px

• Main Content: width: 1920px, height: 695px

Components

Buttons

Variant Background Text Border Height Radius

Ghost transparent #6D89B5 none

Interactive States

Focus

• MUST use 2px outline with accent color (#155BD0 )

• MUST use 2px outline-offset

• NEVER remove focus indicators

Hover

• Buttons (primary): lighten background by 10%

• Buttons (secondary): use #0858DC background

• List items: use #0858DC 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