Monzo UI Skills

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

When to Apply

Reference these guidelines when:

• Building light-mode interfaces
• Creating Monzo-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)
• SHOULD reduce color palette (currently 15 colors detected)
• 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	#C1C5C8	rgb(193,197,200)	Cards, modals, raised surfaces
surface-overlay	#DEDEDE	rgb(222,222,222)	Overlays, tooltips, dropdowns
text-primary	#606366	rgb(96,99,102)	Headings, body text
text-2	#494D50	rgb(73,77,80)	Additional text
text-secondary	#BEC4C7	rgb(190,196,199)	Secondary, muted text
border-default	#8A8D8F	rgb(138,141,143)	Subtle borders, dividers
destructive	#ED4948	rgb(237,73,72)	Error states, delete actions

Typography

• MUST use Inter as primary font family
• SHOULD use single font family for consistency
• MUST use 48px / 700 for primary headings
• MUST use 21px / extra_bold 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	48px	700	#F0F1EE	1
body	Inter	21px	extra_bold	#ED4948	1
body-secondary	Inter	19px	300	#723C7E	1
text-17px	Inter	17px	semi_bold	#373737	1
text-16px	Inter	16px	400	#9EA0A2	1
text-15px	Inter	15px	400	#606366	1
text-15px	Inter	15px	400	#494D50	1
text-15px	Inter	15px	400	#BEC4C7	1
text-15px	Inter	15px	400	#C4C6BC	1
text-13px	Inter	13px	400	#4D4D4D	1

Typography Reference

Font Families:

• Inter (used 16x)

Font Sizes: 8px, 9px, 11px, 12px, 13px, 15px, 16px, 17px, 19px, 21px, 48px

Spacing

• MUST use 4px grid for spacing
• SHOULD use spacing from scale: 2px, 4px, 5px, 6px, 9px, 11px, 20px, 54px
• 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: 3px, 4px, 6px, 16px, 25px
• SHOULD use 25px+ radius for pill-shaped elements
• MUST use 1px border width consistently
• SHOULD use 16px 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: 3px, 4px, 6px, 16px, 25px

Layout

• MUST design for 1920px base viewport width
• SHOULD use consistent element widths: 12px, 116px, 43px, 60px, 299px
• 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: 1470px, height: 870px
• Main Content: width: 1455px, height: 762px
• Header: height: 82px

Components

Buttons

Variant	Background	Text	Border	Height	Radius
Ghost	transparent	#494D50	none	-	-

Interactive States

Focus

• MUST use 2px outline with accent color (#5E6AD2)
• MUST use 2px outline-offset
• NEVER remove focus indicators

Hover

• Buttons (primary): lighten background by 10%
• Buttons (secondary): use #C1C5C8 background
• List items: use #C1C5C8 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