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