Beehiiv UI Skills

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

When to Apply

Reference these guidelines when:

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

Colors

• SHOULD use light backgrounds for primary surfaces
• MUST use #221FAB as page background (surface-base)
• MUST use #221FAB for primary actions and focus states (accent)
• SHOULD reduce color palette (currently 19 colors detected)
• MUST maintain text contrast ratio of at least 4.5:1 for accessibility

Semantic Tokens

Token	HEX	RGB	Usage
surface-base	#221FAB	rgb(34,31,171)	Page background
surface-raised	#070512	rgb(7,5,18)	Cards, modals, raised surfaces
text-primary	#B6B8E7	rgb(182,184,231)	Headings, body text
text-secondary	#B9B7BF	rgb(185,183,191)	Secondary, muted text
text-tertiary	#626076	rgb(98,96,118)	Additional text
border-default	#252494	rgb(37,36,148)	Subtle borders, dividers
accent	#221FAB	rgb(34,31,171)	Primary actions, links, focus

Typography

• MUST use Inter as primary font family
• SHOULD use single font family for consistency
• MUST use 51px / 700 for primary headings
• MUST use 12px / 400 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	51px	700	#EF40B0	1
heading-2	Inter	51px	700	#F7F7F8	1
heading-3	Inter	51px	700	#F5F5F6	1
text-41px	Inter	41px	400	#B8B7BE	1
text-34px	Inter	34px	700	#F4F4F5	1
text-26px	Inter	26px	semi_bold	#CDCCD1	1
text-23px	Inter	23px	semi_bold	#9B99A5	1
text-23px	Inter	23px	500	#CAC9D0	1
text-23px	Inter	23px	700	#D8D7DB	1
text-23px	Inter	23px	semi_bold	#D1D0D5	1

Typography Reference

Font Families:

• Inter (used 61x)

Font Sizes: 5px, 8px, 9px, 10px, 11px, 12px, 13px, 14px, 15px, 16px, 17px, 18px, 19px, 20px, 21px, 22px, 23px, 26px, 34px, 41px, 51px

Spacing

• MUST use 4px grid for spacing
• SHOULD use spacing from scale: 4px, 5px, 15px, 21px, 23px, 53px, 56px, 79px
• SHOULD use 4px 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
• SHOULD limit border widths to: 1px, 2px
• 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

Layout

• MUST design for 1920px base viewport width
• SHOULD use consistent element widths: 13px, 14px, 26px, 31px, 65px
• 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: 999px
• Header: height: 78px

Components

Buttons

Variant	Background	Text	Border	Height	Radius
Ghost	transparent	#B6B8E7	none	-	-

Interactive States

Focus

• MUST use 2px outline with accent color (#221FAB)
• MUST use 2px outline-offset
• NEVER remove focus indicators

Hover

• Buttons (primary): lighten background by 10%
• Buttons (secondary): use #070512 background
• List items: use #070512 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