Dark Professional Design System for Report Websites

Apply a distinctive dark professional visual identity to generated research report websites using Tailwind CSS v4 + shadcn/ui. This design system creates sites that feel like a premium data terminal crossed with a high-end law publication — dense with information yet elegant and readable.

Design Philosophy

Tone: Sophisticated, authoritative, data-rich. Think Bloomberg Terminal meets The Economist's digital edition.

Differentiation: The signature element is the warm amber accent system against deep cool backgrounds — every interactive element glows with intention. Typography pairs a refined serif display face with a crisp humanist sans-serif body, creating tension between editorial authority and modern clarity.

Theme System: Color accents are swappable via theme presets (8 built-in options) or community registries, while layout, typography, and animations remain consistent.

Color System

Colors are defined as Tailwind @theme tokens in app.css and can be overridden by theme preset CSS files. Use Tailwind utility classes for all color references — never hardcode color values.

Core Palette

bg-bg-primary       → #0f1117   Deep space — main background
bg-bg-secondary     → #161922   Elevated surface — cards, panels
bg-bg-tertiary      → #1c1f2e   Recessed areas — code blocks, inputs
bg-bg-hover         → #232738   Hover state for interactive surfaces

text-text-primary    → #e8e6e1   Warm white — body text
text-text-secondary  → #9a9690   Muted warm — secondary text, labels
text-text-tertiary   → #5e5a55   Dim — disabled text, timestamps

text-accent-primary  → #d4a853   Amber gold — primary actions, highlights
text-accent-secondary → #2d9e8f  Teal — secondary interactive elements
text-accent-tertiary → #6366f1   Indigo — links, tertiary actions

border-border-primary → #2a2d3a  Subtle borders between sections
border-border-accent  → rgba(212, 168, 83, 0.2)  Amber border at 20% opacity

shadcn Semantic Tokens

These map to the dark theme by default and are overridden by theme presets:

--color-primary          → accent-primary (gold by default)
--color-primary-foreground → bg-primary
--color-secondary        → bg-tertiary
--color-muted            → bg-tertiary
--color-muted-foreground → text-secondary
--color-destructive      → error
--color-border           → border-primary
--color-ring             → accent-primary

Typography

Font Stack

Load from Google Fonts:

• Display/Headings: font-display → "DM Serif Display", Georgia, serif — Elegant, authoritative serif
• Body/UI: font-body → "IBM Plex Sans", "Helvetica Neue", sans-serif — Crisp, professional
• Code/Data: font-mono → "IBM Plex Mono", "Consolas", monospace — Clean monospace for numbers

Type Treatments

• Headings: font-display text-text-primary with tracking-tight
• Body: font-body text-text-primary with leading-[1.7] max-w-[72ch]
• Labels/Captions: text-xs uppercase tracking-wide text-text-secondary
• Data/Numbers: font-mono text-accent-primary tabular-nums
• Blockquotes: italic text-text-secondary border-l-3 border-l-accent-primary bg-bg-secondary

Spacing

Use Tailwind's spacing scale. Key layout patterns:

• Between sections (H3): mb-16
• Inside cards/panels: p-5 or space-y-5
• Tab bar height: py-4 (maps to --tab-bar-height: 4rem)
• Page horizontal padding: px-6
• Max content width: max-w-[var(--max-content-width)] (1200px), centered with mx-auto

Component Styling

All components use Tailwind utility classes + shadcn UI primitives. Import cn from @/lib/utils for conditional class merging.

Tabbed Navigation (TabbedLayout)

• Background: bg-bg-secondary
• Bottom border: border-b border-border-primary
• Active tab: text-accent-primary + animated indicator via bg-gradient-tab-indicator
• Inactive tab: text-text-tertiary hover:text-text-secondary
• Glassmorphism on scroll: glass shadow-lg utility class
• Tab labels: text-sm font-medium uppercase tracking-[0.08em]
• Presentation toggle: shadcn Button variant="outline"

Cards and Panels

• Use shadcn Card / CardContent components
• Calculator: border-l-3 border-l-accent-primary bg-gradient-gold-subtle shadow-md
• Scenario slider: border-l-3 border-l-accent-secondary bg-gradient-teal-subtle shadow-md
• Hover lift: framer-motion whileHover={{ y: -2 }}

Interactive Elements (Calculators, Sliders)

• Input fields: shadcn Input with font-mono bg-bg-primary border-border-primary shadow-inset
• Focus: focus-visible:border-accent-primary focus-visible:ring-[rgba(212,168,83,0.15)]
• Labels: shadcn Label with text-xs uppercase tracking-wide text-text-secondary
• Dividers: shadcn Separator with bg-border-primary
• Result display: font-mono text-[length:var(--font-size-hero)] text-accent-primary tabular-nums
• Range slider: Native <input type="range"> with .scenario-slider CSS class (custom styling in app.css)

Tables (ComparisonTable)

• Use shadcn Table, TableHeader, TableBody, TableHead, TableRow, TableCell
• Header row: bg-bg-tertiary text-xs uppercase tracking-wide font-semibold
• Hover row: inline style background: var(--color-bg-hover)
• Filter buttons: shadcn Button with variant toggling
• Highlighted column: text-accent-primary + subtle gradient background

Citations (CitationCard)

• Use shadcn Collapsible + Badge
• Number badge: font-mono text-xs text-accent-tertiary in a shadcn Badge variant="outline"
• Left border: border-l-3 border-l-accent-tertiary
• Links: text-accent-tertiary text-xs font-mono bg-bg-tertiary with hover lift

Knowledge Vault (KnowledgeVault)

• Use shadcn Accordion, AccordionItem, AccordionTrigger, AccordionContent
• Search input: shadcn Input with pl-12 font-mono shadow-inset
• Expand all: shadcn Button variant="outline"
• Section items: AccordionItem with conditional border/shadow classes

Badges (SectionRenderer)

• Use shadcn Badge variant="outline" with semantic color classes
• VERIFIED: text-success border-[rgba(52,211,153,0.25)]
• ESTIMATE: text-warning border-[rgba(251,191,36,0.25)]
• ILLUSTRATIVE: text-info border-[rgba(96,165,250,0.25)]

Animation Patterns

Use framer-motion for React. Animation tokens are in src/theme/motion.js. Keep animations purposeful and restrained.

Tab Transitions

• Content fade + slide: 300ms, opacity: 0 → 1, y: 8 → 0
• Use AnimatePresence with mode="wait" for clean tab switches

Content Reveals

• Sections animate in on first view with useInView and staggered delays (50ms between siblings)
• Cards: opacity: 0 → 1, y: 16 → 0, 400ms
• Tables: rows stagger in at 30ms intervals
• Numbers/stats: count-up animation over 600ms

Interactive Feedback

• Calculator results: brief scale pulse (1.0 → 1.02 → 1.0) on value change
• Slider: real-time update, no animation delay
• Hover on cards: framer-motion whileHover={{ y: -2 }}
• Button press: framer-motion whileTap={{ scale: 0.95 }}

Presentation Mode (if enabled)

• Auto-advance tabs every 8 seconds
• Progress bar under tabs shows timing
• Section content types in with stagger

Custom Tailwind Utilities

Defined in app.css via @utility blocks:

bg-gradient-surface       — Surface gradient (secondary → tertiary)
bg-gradient-gold-subtle   — Calculator background tint
bg-gradient-teal-subtle   — Scenario slider background tint
bg-gradient-timeline      — Timeline line gradient (gold → teal → indigo)
bg-gradient-tab-indicator — Tab underline gradient (gold → teal)
bg-gradient-hero-text     — Hero title text gradient
bg-gradient-accent-line   — 60px heading accent line
glass                     — Glassmorphism (bg + backdrop-filter)
scrollbar-none            — Hide scrollbar

Responsive Design

Breakpoints

Mobile: < 768px
Tablet: 768px - 1023px
Desktop: >= 1024px

Mobile Adaptations

• Tabs become a horizontal scrollable row (overflow-x-auto scrollbar-none)
• Tables use horizontal scroll
• Calculator inputs stack vertically
• Font sizes reduce: --font-size-hero: 2.5rem on mobile
• Page padding: px-4

Desktop Enhancements

• Tabs are full-width with even spacing
• Comparison tables show all columns
• Page padding: px-6

Accessibility

• All color combinations meet WCAG AA contrast ratios (4.5:1 for text, 3:1 for large text)
• Tab navigation is keyboard accessible (arrow keys, Enter, Tab) via role="tablist" and role="tab"
• Interactive elements have visible focus indicators (focus-visible: with accent-primary outline)
• Animations respect prefers-reduced-motion — all durations reduced to 0.01ms
• All icons have aria-hidden="true" with descriptive text nearby
• Semantic HTML: <nav>, <main>, <header>, <section>
• shadcn components include built-in ARIA attributes (Accordion, Collapsible, etc.)

Note: This design system is dark-mode only by design. Light mode is not supported. The dark professional aesthetic is core to the brand identity of generated report sites.

Theme Presets

8 built-in color presets are available in ${CLAUDE_PLUGIN_ROOT}/templates/src/themes/. Each overrides only semantic color tokens, leaving layout and animation intact. See ${CLAUDE_PLUGIN_ROOT}/skills/design-system/references/registry-guide.md for details.

Reference Files

For framer-motion animation tokens, see ${CLAUDE_PLUGIN_ROOT}/templates/src/theme/motion.js.
For the Tailwind v4 stylesheet with all tokens, see ${CLAUDE_PLUGIN_ROOT}/templates/src/app.css.
For the full token definitions, see ${CLAUDE_PLUGIN_ROOT}/skills/design-system/references/tokens-reference.md.
For registry/theme selection, see ${CLAUDE_PLUGIN_ROOT}/skills/design-system/references/registry-guide.md.