liveblocks-ui-skills

Liveblocks UI Skills

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

When to Apply

Reference these guidelines when:

• Building dark-mode interfaces
• Creating Liveblocks-inspired design systems
• Implementing UIs with Inter font and 4px grid

Colors

• MUST use dark backgrounds (lightness < 20) for primary surfaces - detected lightness: 0
• MUST use #000000 as page background (surface-base)
• SHOULD reduce color palette (currently 11 colors detected)
• MUST maintain text contrast ratio of at least 4.5:1 for accessibility

Semantic Tokens

Token	HEX	RGB	Usage
surface-base	#000000	rgb(0,0,0)	Page background
surface-raised	#E5E5E5	rgb(229,229,229)	Cards, modals, raised surfaces
surface-overlay	#FEFEFE	rgb(254,254,254)	Overlays, tooltips, dropdowns
text-primary	#818181	rgb(129,129,129)	Headings, body text
text-secondary	#5B595A	rgb(91,89,90)	Secondary, muted text
text-tertiary	#B5B5B5	rgb(181,181,181)	Additional text
border-default	#EAEAEA	rgb(234,234,234)	Subtle borders, dividers

Typography

• MUST use Inter as primary font family
• SHOULD use single font family for consistency
• MUST use 54px / 700 for primary headings
• MUST use 19px / 400 for body text
• MUST limit font weights to: medium, regular, bold
• 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	54px	700	#E9E9E9	1
body	Inter	19px	400	#818181	1
body-secondary	Inter	19px	400	#8E8E8E	1
body-secondary	Inter	18px	400	#737373	1
body-secondary	Inter	18px	500	#C4C4C4	1
body-secondary	Inter	17px	400	#707070	1
text-15px	Inter	15px	400	#8E8E8E	1
text-15px	Inter	15px	400	#747474	1
text-15px	Inter	15px	400	#777777	1
text-15px	Inter	15px	400	#797979	1

Typography Reference

Font Families:

• Inter (used 30x)

Font Sizes: 6px, 8px, 11px, 12px, 14px, 15px, 17px, 18px, 19px, 54px

Spacing

• MUST use 4px grid for spacing
• SHOULD use spacing from scale: 1px, 2px, 3px, 4px, 5px, 6px, 7px, 8px
• 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, 5px, 19px
• MUST use 1px border width consistently
• SHOULD use 3px 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, 5px, 19px

Layout

• MUST design for 1920px base viewport width
• SHOULD use consistent element widths: 36px, 48px, 1px, 8px, 47px
• 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: 1855px, height: 1080px
• Main Content: width: 1920px, height: 769px
• Main Content: width: 1920px, height: 559px

Components

Buttons

Variant	Background	Text	Border	Height	Radius
Ghost	transparent	#6B6B6B	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 #E5E5E5 background
• List items: use #E5E5E5 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