Clerk UI Skills

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

When to Apply

Reference these guidelines when:

• Building light-mode interfaces

• Creating Clerk-inspired design systems

• Implementing UIs with Inter font and 4px grid

Colors

• SHOULD use light backgrounds for primary surfaces

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

• MUST use #C4A9F3 for primary actions and focus states (accent )

• SHOULD reduce color palette (currently 12 colors detected)

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

Semantic Tokens

Token HEX RGB Usage

surface-base

#FEFEFE rgb(254,254,254) Page background

surface-raised

#090909 rgb(9,9,9) Cards, modals, raised surfaces

text-primary

#5C5C5C rgb(92,92,92) Headings, body text

text-secondary

#98979D rgb(152,151,157) Secondary, muted text

text-tertiary

#2F2F2F rgb(47,47,47) Additional text

border-default

#E4E4E1 rgb(228,228,225) Subtle borders, dividers

accent

#C4A9F3 rgb(196,169,243) Primary actions, links, focus

Typography

• MUST use Inter as primary font family

• SHOULD use single font family for consistency

• MUST use 66px / 700 for primary headings

• MUST use 26px / 700 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 66px 700 #262628 1

body

Inter 26px 700 #292929 1

text-19px

Inter 19px 500 #4D4D4D 1

text-18px

Inter 18px 500 #303030 1

text-18px

Inter 18px 400 #525252 1

text-17px

Inter 17px 500 #E9E9E9 1

text-17px

Inter 17px 400 #838285 1

text-16px

Inter 16px 500 #2F2F2F 1

text-16px

Inter 16px 300 #F5F5F5 1

text-15px

Inter 15px 400 #BDBDBD 1

Typography Reference

Font Families:

• Inter (used 28x)

Font Sizes: 9px, 11px, 12px, 14px, 15px, 16px, 17px, 18px, 19px, 26px, 66px

Spacing

• MUST use 4px grid for spacing

• SHOULD use spacing from scale: 1px, 2px, 4px, 5px, 16px, 37px, 49px, 51px

• SHOULD use 5px 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: 4px, 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: 4px, 6px, 7px

Layout

• MUST design for 1920px base viewport width

• SHOULD use consistent element widths: 8px, 52px, 44px, 363px, 71px

• 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: 584px

Components

• MUST use 0px height for input fields

Buttons

Variant Background Text Border Height Radius

Ghost transparent #BDBDBD none

Inputs

• Height: 0px

Interactive States

Focus

• MUST use 2px outline with accent color (#C4A9F3 )

• MUST use 2px outline-offset

• NEVER remove focus indicators

Hover

• Buttons (primary): lighten background by 10%

• Buttons (secondary): use #090909 background

• List items: use #090909 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