Things UI Skills

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

When to Apply

Reference these guidelines when:

• Building light-mode interfaces
• Creating Things-inspired design systems
• Implementing UIs with Inter font and 8px grid

Colors

• SHOULD use light backgrounds for primary surfaces
• MUST use #EEF2F5 as page background (surface-base)
• MUST use #729AE0 for primary actions and focus states (accent)
• SHOULD limit color palette to 5 distinct colors
• MUST maintain text contrast ratio of at least 4.5:1 for accessibility

Semantic Tokens

Token	HEX	RGB	Usage
surface-base	#EEF2F5	rgb(238,242,245)	Page background
text-primary	#729AE0	rgb(114,154,224)	Headings, body text
text-2	#5A5E61	rgb(90,94,97)	Additional text
text-tertiary	#2F343B	rgb(47,52,59)	Additional text
accent	#729AE0	rgb(114,154,224)	Primary actions, links, focus

Typography

• MUST use Inter as primary font family
• SHOULD use single font family for consistency
• MUST use 49px / 700 for primary headings
• MUST use 23px / 400 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	49px	700	#2F343B	1
body	Inter	23px	400	#5A5E61	1
text-20px	Inter	20px	500	#729AE0	1
text-19px	Inter	19px	semi_bold	#9298A0	1
text-14px	Inter	14px	400	#9499A1	1
text-14px	Inter	14px	400	#989CA4	1
caption	Inter	11px	400	#989DA4	1

Typography Reference

Font Families:

• Inter (used 7x)

Font Sizes: 11px, 14px, 19px, 20px, 23px, 49px

Spacing

• MUST use 8px grid for spacing
• SHOULD use spacing from scale: 72px
• SHOULD use 72px as default gap between elements
• NEVER use arbitrary spacing values (use design scale)
• SHOULD maintain consistent padding within containers

Borders

• NEVER use arbitrary border-radius values (use design scale)
• SHOULD use subtle borders (1px) for element separation

Layout

• MUST design for 1920px base viewport width
• SHOULD use consistent element widths: 35px, 64px
• 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: 1080px
• Main Content: width: 1920px, height: 1024px

Components

Interactive States

Focus

• MUST use 2px outline with accent color (#729AE0)
• MUST use 2px outline-offset
• NEVER remove focus indicators

Hover

• Buttons (primary): lighten background by 10%
• Buttons (secondary): use surface-raised background
• List items: use surface-raised 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