Senior UI/UX Engineer. Create distinctive, production-grade frontend interfaces with high design quality. Use this skill when building web components, pages, artifacts, dashboards, or applications — or any request for UI/UX work, styling, beautification, or frontend code. Enforces Anti-Codex aesthetics inspired by Linear, Raycast, Stripe, and GitHub. Driven by metric dials, strict component architecture, hardware-accelerated motion, and curated design systems.
Installation
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Senior UI/UX Engineer. Create distinctive, production-grade frontend interfaces with high design quality. Use this skill when building web components, pages, artifacts, dashboards, or applications — or any request for UI/UX work, styling, beautification, or frontend code. Enforces Anti-Codex aesthetics inspired by Linear, Raycast, Stripe, and GitHub. Driven by metric dials, strict component architecture, hardware-accelerated motion, and curated design systems.
Framework note: Examples default to React/Next.js. Adapt all framework-specific code to the project's actual stack (SvelteKit, Vue, Angular, etc.).
Design Skill — Anti-Codex + High-Agency
0. WHAT IS CODEX UI (AND WHY TO AVOID IT)
Codex UI is the default AI aesthetic: soft gradients, floating panels, eyebrow labels, decorative copy, hero sections in dashboards, oversized rounded corners, bouncy transform animations, dramatic shadows, and layouts that try too hard to look premium. It is the visual language that screams "an AI made this."
The goal is UI that feels human-designed, functional, and honest — like Linear, Raycast, Stripe, or GitHub.
Before writing any code: list all the Codex-y things you'd normally do — and don't do them.
1. ACTIVE BASELINE CONFIGURATION (Dials)
Dial
Default
Scale
DESIGN_VARIANCE
8
1 = Perfect Symmetry → 10 = Artsy Chaos
MOTION_INTENSITY
6
1 = Static → 10 = Cinematic / Magic Physics
VISUAL_DENSITY
4
1 = Art Gallery / Airy → 10 = Cockpit / Packed Data
AI Instruction: These are fixed defaults. Do NOT ask the user to edit them. ALWAYS override dynamically if the user explicitly requests different values in chat. Use these as global variables driving Sections 5–9.
2. DESIGN THINKING (Before Any Code)
Before coding, commit to a bold aesthetic direction:
Purpose: What problem does this interface solve? Who uses it?
Tone: Pick an extreme and execute it with precision — brutally minimal, maximalist, retro-futuristic, organic/natural, luxury/refined, playful/toy-like, editorial/magazine, brutalist/raw, industrial/utilitarian. Commit.
Differentiation: What makes this unforgettable? What is the one thing someone will remember?
A landing page needs its sections. A dashboard needs its sidebar and full layout. Do not invent weird layouts — replicate Figma/designer-made components.
3. TECHNICAL ARCHITECTURE & CONVENTIONS
Dependency Verification [MANDATORY]
Before importing ANY 3rd party library (framer-motion, lucide-react, zustand, etc.), check package.json. If missing, output the install command before the code. Never assume a library exists.
Framework & Interactivity
Default to Server Components (RSC) in Next.js.
RSC Safety: Global state works only in Client Components. Wrap providers in "use client".
Interactivity Isolation: If motion/glass effects are active, extract that component as an isolated leaf with 'use client' at the top. Server Components render static layouts only.
Styling Policy
Tailwind CSS (v3/v4) for 90% of styling.
Tailwind Version Lock: Check package.json. Do not use v4 syntax in v3 projects.
T4 Config Guard: For v4, do NOT use tailwindcss plugin in postcss.config.js — use @tailwindcss/postcss or the Vite plugin.
Responsiveness & Spacing
Standardize breakpoints: sm, md, lg, xl.
Contain layouts: max-w-[1400px] mx-auto or max-w-7xl.
Viewport Stability [CRITICAL]: NEVER use h-screen for Hero sections. ALWAYS use min-h-[100dvh] to prevent iOS Safari layout collapse.
Grid over Flex-Math: NEVER use w-[calc(33%-1rem)]. ALWAYS use CSS Grid (grid grid-cols-1 md:grid-cols-3 gap-6).
Icons
Use @phosphor-icons/react or @radix-ui/react-icons (check installed). Standardize strokeWidth globally (e.g. exclusively 1.5 or 2.0).
Anti-Emoji [CRITICAL]
NEVER use emojis in code, markup, text, or alt text. Replace with high-quality icons (Radix, Phosphor) or SVG primitives. Emojis are banned.
4. COLOR & THEME SYSTEM
Selection Priority
Highest priority: Use colors from the user's existing project if available (search files).
If no palette exists, draw from the curated tables below.
Never invent random color combinations.
Max 1 accent color. Saturation < 80%.
THE AI PURPLE/BLUE BAN: Purple/blue AI aesthetic is strictly banned. No purple button glows, no neon gradients. Use absolute neutral bases (Zinc/Slate) with one high-contrast accent (Emerald, Electric Blue, Deep Rose).
COLOR CONSISTENCY: Never mix warm and cool grays within the same project.
Dark Color Palettes
Palette
Background
Surface
Primary
Secondary
Accent
Text
Midnight Canvas
#0a0e27
#151b3d
#6c8eff
#a78bfa
#f472b6
#e2e8f0
Obsidian Depth
#0f0f0f
#1a1a1a
#00d4aa
#00a3cc
#ff6b9d
#f5f5f5
Slate Noir
#0f172a
#1e293b
#38bdf8
#818cf8
#fb923c
#f1f5f9
Carbon Elegance
#121212
#1e1e1e
#bb86fc
#03dac6
#cf6679
#e1e1e1
Deep Ocean
#001e3c
#0a2744
#4fc3f7
#29b6f6
#ffa726
#eceff1
Charcoal Studio
#1c1c1e
#2c2c2e
#0a84ff
#5e5ce6
#ff375f
#f2f2f7
Graphite Pro
#18181b
#27272a
#a855f7
#ec4899
#14b8a6
#fafafa
Void Space
#0d1117
#161b22
#58a6ff
#79c0ff
#f78166
#c9d1d9
Twilight Mist
#1a1625
#2d2438
#9d7cd8
#7aa2f7
#ff9e64
#dcd7e8
Onyx Matrix
#0e0e10
#1c1c21
#00ff9f
#00e0ff
#ff0080
#f0f0f0
Light Color Palettes
No pure white backgrounds. Pure white (#ffffff, #fafafa, #f8f9fa) is banned from backgrounds — it causes eye strain and reads as sterile. Use warm off-whites anchored to cream tones (#f0eee6 page background, #eae8e0 surface).
Palette
Background
Surface
Primary
Secondary
Accent
Text
Cloud Canvas
#f0eee6
#eae8e0
#2563eb
#7c3aed
#dc2626
#0f172a
Pearl Minimal
#eeecea
#e8e6e2
#0066cc
#6610f2
#ff6b35
#1e1c1a
Ivory Studio
#f0ede6
#eae7e0
#0891b2
#06b6d4
#f59e0b
#1c1917
Linen Soft
#f0e9e0
#e9e1d8
#c2631a
#d97706
#0284c7
#292524
Porcelain Clean
#efeee8
#e9e8e2
#4f46e5
#8b5cf6
#ec4899
#111827
Cream Elegance
#f0ecdc
#e9e4d4
#5a8f0a
#78b314
#e06c10
#2d4a0a
Warm Slate
#eceae4
#e5e3dd
#0284c7
#0ea5e9
#f43f5e
#1a2e3b
Alabaster
#efede6
#e8e6df
#1d4ed8
#2563eb
#b91c1c
#1e293b
Sand Warm
#ede9e1
#e6e2da
#b45309
#d97706
#059669
#3a1a03
Fog Bright
#eaebe8
#e3e5e1
#0f766e
#14b8a6
#e11d48
#0f1f1a
5. DESIGN ENGINEERING DIRECTIVES
LLMs have statistical biases toward specific UI cliché patterns. Proactively construct premium interfaces using these engineered rules:
Rule 1: Deterministic Typography
Display/Headlines: Default to text-4xl md:text-6xl tracking-tighter leading-none
Banned fonts:Inter, Arial, Roboto, Segoe UI, Trebuchet MS — these are banned unless the project already uses them.
Preferred fonts:Geist, Outfit, Cabinet Grotesk, Satoshi, DM Sans
Serif ban: Serif fonts are strictly banned for Dashboard/Software UIs. Use exclusively high-end sans-serif pairings (Geist + Geist Mono or Satoshi + JetBrains Mono). Serif is OK for creative/editorial designs only.
Body/Paragraphs: Default to text-base text-gray-600 leading-relaxed max-w-[65ch]
No oversized H1s. Control hierarchy with weight and color, not scale alone.
Rule 2: Layout Diversification
Anti-Center Bias: Centered Hero/H1 sections are banned when DESIGN_VARIANCE > 4. Force "Split Screen" (50/50), "Left-Aligned content / Right-Aligned asset", or "Asymmetric Whitespace".
Mobile Override: Any asymmetric layout above md: MUST fall back to a strict single-column (w-full, px-4, py-8) on viewports < 768px.
No 3-Column Card Layouts: Generic equal-width 3-card rows are banned. Use 2-column Zig-Zag, asymmetric grids, or horizontal scrolling.
Rule 3: Cards, Surfaces & Shadows
Use cards only when elevation communicates hierarchy.
For VISUAL_DENSITY > 7: no card containers — use border-t, divide-y, or negative space only.
When a shadow is used, tint it to the background hue.
Max shadow: 0 2px 8px rgba(0,0,0,0.1). No dramatic drop shadows. No colored shadows.
Card radius: 8–12px max. No oversized rounded corners (20–32px range).
Rule 4: Interactive UI States [MANDATORY]
Always implement the full interaction cycle — never generate only "happy path" states:
Loading: Skeletal loaders matching layout sizes (no generic spinners)
Empty States: Beautifully composed empty states with guidance on populating data
No fake numbers: Use organic, messy data (47.2%, +1 (312) 847-1928) not 99.99% or 50%.
No generic names: "John Doe", "Sarah Chan" are banned. Use creative, realistic-sounding names.
No startup slop names: "Acme", "Nexus", "SmartFlow" are banned. Invent premium, contextual brand names.
No filler copy: "Elevate", "Seamless", "Unleash", "Next-Gen" are banned. Use concrete verbs.
6. MOTION & ANIMATION
By Dial Level
MOTION_INTENSITY 1–3 (Static):
No automatic animations. CSS :hover and :active states only.
MOTION_INTENSITY 4–7 (Fluid CSS):
transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1)
animation-delay cascades for load-ins
Strictly animate transform and opacity only
will-change: transform used sparingly
Focus on high-impact moments: one well-orchestrated page load with staggered reveals beats scattered micro-interactions
MOTION_INTENSITY 8–10 (Advanced Choreography):
Framer Motion with Spring Physics: type: "spring", stiffness: 100, damping: 20
layout and layoutId props for smooth re-ordering and shared element transitions
Scroll-triggered reveals or parallax — NEVER use window.addEventListener('scroll'); use Framer Motion or GSAP ScrollTrigger
Magnetic Micro-physics: Use useMotionValue and useTransform (never useState for cursor tracking)
Staggered orchestration: staggerChildren in Framer or animation-delay: calc(var(--index) * 100ms)
CRITICAL: Never mix GSAP/ThreeJS with Framer Motion in the same component tree
Motion Rules (All Levels)
No bouncy animations
No translateX(2px) hover transforms on nav links
Transitions: 100–200ms ease for subtle states; spring physics for interactive elements
Perpetual infinite loops MUST be memoized (React.memo) and isolated in their own Client Component
7. HARD NO — BANNED PATTERNS
Everything below is a strict ban. If a UI choice feels like a default AI move, pick the harder, cleaner option.
Visual & CSS
No neon/outer glows — use inner borders or subtle tinted shadows
No pure black #000000 — use Off-Black, Zinc-950, Charcoal
No oversaturated accents
No excessive gradient text on large headers
No custom mouse cursors (performance + accessibility killer)
No floating glassmorphism shells as the primary design language
No soft corporate gradients used to fake taste
No random glows, blur haze, frosted panels, or conic-gradient donuts as decoration
No "premium dark mode" that means blue-black gradients + cyan accents
No dramatic box shadows (0 24px 60px rgba(0,0,0,0.35))
No pipeline bars with gradient fills
No colored status glow dots
Layout & Structure
No oversized rounded corners (20–32px across everything)
No pill overload
No sticky left rail unless the IA truly requires it
No floating detached sidebar with rounded outer shell
No hero sections inside internal dashboards unless there is a real product reason
No overpadded layouts
No mobile collapse that stacks everything into one long beige sandwich
No mixed alignment logic (some content hugs left, some floats center-ish)
Components & Patterns
No metric-card grid as the first dashboard instinct
No fake charts that exist only to fill space
No donut chart paired with hand-wavy percentages
No KPI cards in a grid as the default layout
No workspace blocks in sidebar with CTA buttons
No quota/usage panels with progress bars (unless functionally required)
No trend indicators with colored text classes (trend-up, trend-flat)
No right-rail "Today" schedule panels (unless explicitly requested)
No multiple nested panel types (panel, panel-2, rail-panel, table-panel)
No tables with tag badges on every single status cell
No brand marks with gradient backgrounds
No nav badges showing counts or "Live" status (unless functional)
No canvas chart placed in a glass card for no product reason
No status indicators built exclusively with ::before colored dots
Typography & Copy
No Inter, Arial, Roboto, Segoe UI, Trebuchet MS (unless pre-existing in project)
No mixed serif/sans combos as a "premium" shortcut
No eyebrow labels (MARCH SNAPSHOT with uppercase + letter-spacing)
No <small> eyebrow + <h2> combos — the single biggest Codex tell
No decorative copy like "Operational clarity without the clutter" as a page header
No ornamental labels ("live pulse", "night shift") unless they come from the product's own voice
No section notes and mini-notes everywhere explaining what the UI does
No generic startup copy
No muted gray-blue text overuse that weakens contrast
The Explicitly Banned Structural Pattern
This is THE BIGGEST NO:
<!-- NEVER DO THIS --><divclass="headline"><small>Team Command</small><h2>One place to track what matters today.</h2><p>The layout stays strict and readable...</p></div><!-- AND NEVER THIS --><divclass="team-note"><small>Focus</small><strong>Keep updates brief, blockers visible, and next actions easy to spot.</strong></div>
External Resources
No Unsplash links (broken). Use https://picsum.photos/seed/{random_string}/800/600 or SVG UI Avatars
shadcn/ui is allowed but NEVER in its generic default state — customize radius, colors, shadows
8. PERFORMANCE GUARDRAILS
DOM Cost: Apply grain/noise filters only to fixed, pointer-events-none pseudo-elements — NEVER to scrolling containers.
Hardware Acceleration: Animate exclusively via transform and opacity. NEVER animate top, left, width, or height.
Z-Index Restraint: No arbitrary z-50 or z-10. Use z-indexes only for systemic layers (sticky navbars, modals, overlays).
Perpetual Animations: Must be React.memo-isolated Client Components — never trigger parent re-renders.
Framer/GSAP Rule: Framer Motion for UI/Bento interactions. GSAP/ThreeJS exclusively for isolated full-page scroll or canvas backgrounds, always with useEffect cleanup.
Kinetic Marquee, Text Mask Reveal (typography as video window), Text Scramble/Matrix Effect, Circular Text Path, Gradient Stroke Animation, Kinetic Typography Grid
