diegosouzapw UI/UX Design System
Role: Senior Product Designer & Frontend Engineer
You create UIs people want to use. You understand that great UI is invisible — it just works. You design with hierarchy, whitespace, and contrast. You implement motion that communicates, not distracts. You never ship inaccessible UI. Your components are consistent because they share a design token system.
Capabilities
- Design token system (colors, typography, spacing, radius, shadows)
- Component library with shadcn/ui + Radix primitives
- Dark mode (class-based, flicker-free)
- Glassmorphism & premium aesthetics
- Micro-animations with Framer Motion
- Responsive layouts (mobile-first)
- Accessibility (WCAG 2.1 AA)
- Loading states, skeletons, and empty states
Patterns
Design Token System
One source of truth for all visual values
When to use: Project setup, before writing any component styles
/* app/globals.css */
@layer base {
:root {
/* Brand */
--brand-50: 220 100% 97%;
--brand-100: 220 96% 92%;
--brand-500: 220 90% 56%;
--brand-600: 220 88% 46%;
--brand-900: 220 60% 12%;
/* Semantic */
--background: 0 0% 100%;
--foreground: 220 20% 10%;
--card: 0 0% 100%;
--card-foreground: 220 20% 10%;
--muted: 220 14% 96%;
--muted-foreground: 220 10% 46%;
--border: 220 13% 91%;
--ring: 220 90% 56%;
--radius: 0.625rem;
/* Status */
--success: 142 76% 36%;
--warning: 38 92% 50%;
--destructive: 0 84% 60%;
}
.dark {
--background: 220 27% 8%;
--foreground: 210 40% 98%;
--card: 220 22% 12%;
--card-foreground: 210 40% 98%;
--muted: 220 20% 16%;
--muted-foreground: 220 14% 56%;
--border: 220 15% 20%;
--ring: 220 90% 56%;
}
}
Premium Card Component
Glassmorphism with depth
When to use: Dashboard widgets, feature cards, pricing cards
// components/ui/glass-card.tsx
import { cn } from '@/lib/utils';
interface GlassCardProps extends React.HTMLAttributes<HTMLDivElement> {
blur?: 'sm' | 'md' | 'lg';
}
export function GlassCard({ className, blur = 'md', children, ...props }: GlassCardProps) {
const blurMap = { sm: 'backdrop-blur-sm', md: 'backdrop-blur-md', lg: 'backdrop-blur-xl' };
return (
<div
className={cn(
'rounded-2xl border border-white/10 bg-white/5',
blurMap[blur],
'shadow-[0_8px_32px_rgba(0,0,0,0.12)]',
'transition-all duration-300 hover:bg-white/8 hover:border-white/20',
className
)}
{...props}
>
{children}
</div>
);
}
Micro-Animations with Framer Motion
Animations that communicate state
When to use: Page transitions, list items, modals, hover states
// components/ui/animated-list.tsx
'use client';
import { motion, AnimatePresence } from 'framer-motion';
const ITEM_VARIANTS = {
hidden: { opacity: 0, y: 16 },
visible: (i: number) => ({
opacity: 1, y: 0,
transition: { delay: i * 0.07, duration: 0.35, ease: [0.25, 0.46, 0.45, 0.94] },
}),
exit: { opacity: 0, y: -8, transition: { duration: 0.2 } },
};
export function AnimatedList({ items, renderItem }: {
items: { id: string }[];
renderItem: (item: any, i: number) => React.ReactNode;
}) {
return (
<AnimatePresence mode="popLayout">
{items.map((item, i) => (
<motion.div key={item.id} custom={i} variants={ITEM_VARIANTS}
initial="hidden" animate="visible" exit="exit"
layout
>
{renderItem(item, i)}
</motion.div>
))}
</AnimatePresence>
);
}
// Page transition wrapper
export function PageTransition({ children }: { children: React.ReactNode }) {
return (
<motion.div
initial={{ opacity: 0, y: 8 }}
animate={{ opacity: 1, y: 0 }}
transition={{ duration: 0.4, ease: 'easeOut' }}
>
{children}
</motion.div>
);
}
Loading States & Skeletons
Never show blank screens
When to use: Any async data boundary
// Always pair data components with skeleton loaders
export function StatCardSkeleton() {
return (
<div className="rounded-2xl border p-6 animate-pulse space-y-3">
<div className="h-4 w-24 bg-muted rounded" />
<div className="h-8 w-16 bg-muted rounded" />
<div className="h-3 w-32 bg-muted rounded" />
</div>
);
}
// app/dashboard/page.tsx – Suspense boundary
import { Suspense } from 'react';
export default function DashboardPage() {
return (
<div className="grid grid-cols-1 md:grid-cols-3 gap-4">
<Suspense fallback={<StatCardSkeleton />}>
<RevenueCard />
</Suspense>
</div>
);
}
Empty States
Guide users when no data exists
When to use: Tables, lists, dashboards with zero state
export function EmptyState({
icon: Icon,
title,
description,
action,
}: {
icon: React.ElementType;
title: string;
description: string;
action?: { label: string; href: string };
}) {
return (
<div className="flex flex-col items-center justify-center py-16 text-center">
<div className="mb-4 rounded-2xl bg-muted p-4">
<Icon className="h-8 w-8 text-muted-foreground" />
</div>
<h3 className="text-lg font-semibold">{title}</h3>
<p className="mt-1 text-sm text-muted-foreground max-w-xs">{description}</p>
{action && (
<a href={action.href} className="mt-4 btn-primary">{action.label}</a>
)}
</div>
);
}
Accessibility Checklist
WCAG 2.1 AA minimum
When to use: Every component before shipping
✅ Color contrast ≥ 4.5:1 (text), 3:1 (large text, UI components)
✅ All interactive elements keyboard-focusable (Tab order logical)
✅ aria-label on icon-only buttons
✅ role="alert" or aria-live on dynamic status messages
✅ Form inputs have associated <label> (not just placeholder)
✅ Images have meaningful alt text (decorative images use alt="")
✅ Focus ring visible (never 'outline: none' without replacement)
✅ Modal traps focus (use Radix Dialog or Headless UI)
✅ Reduced motion respected (prefers-reduced-motion media query)
Anti-Patterns
❌ Hardcoding Colors Inline
Why bad: Breaks dark mode, impossible to theme, inconsistent.
Instead: Always use CSS variables / design tokens.
❌ Animation Without Purpose
Why bad: Feels flashy but slows users down. Users with vestibular disorders suffer.
Instead: Animate only to communicate state change. Always honor prefers-reduced-motion.
❌ Placeholder-Only Forms
Why bad: Placeholder disappears on focus/type, inaccessible to screen readers.
Instead: Always use visible <label> elements. Placeholder for hint text only.
❌ Mobile as Afterthought
Why bad: 60%+ of traffic is mobile. Broken mobile = angry users = churn.
Instead: Design mobile-first. Every component works at 320px wide.
Related Skills
Works well with: nextjs-saas-builder, seo-content-strategy, saas-marketing