ui

UI

Components

• components/ui: primitives without data or store access. components/shared: reused app components. features/<feature>/components: domain UI.
• Add primitives with {{EXEC_COMMAND}} shadcn@latest add <component>; do not hand-write them.
• Find the primitive library first: style in components.json (base-… or radix-…), else package.json (@base-ui/react or @radix-ui/*). Never mix them.
• Merge classes with cn() (@/lib/utils), never template strings.
• Data-driven UI has loading (a skeleton of the final size), empty and error states.
• Animate with motion/react and respect reduced motion.

Tailwind CSS 4

• Theme tokens and the default scale only (bg-background, p-4). No hex, rgb or arbitrary values like p-[13px].
• v4 class names: bg-linear-to-r instead of bg-gradient-to-r, size-4 instead of w-4 h-4.
• Mobile first from 320px; check every breakpoint up to xl.

Accessibility

• Semantic HTML: button for actions, links for navigation, one h1 per page, no skipped heading levels.
• Every control has a name: visible text, a <label>, or aria-label if nothing is visible.
• Everything works by keyboard and focus is visible.
• Dialogs and menus use the primitive's focus handling, never a custom focus trap.
• Text contrast meets WCAG AA (4.5:1). Never show state with color alone.
• Meaningful alt text; alt="" for decorative images.

Bans

• onClick on div or span.
• The generic "AI look": indigo or purple defaults, gradients everywhere, rounded-2xl on everything, identical card grids. Lorem ipsum.

type StatCardProps = { label: string; value: string; className?: string };

export function StatCard({ label, value, className }: StatCardProps) { return ( <section className={cn("rounded-lg border bg-card p-4 md:p-6", className)}> {label} {value} ); }

</example>