Split hero with live panel

import { ArrowRight } from 'lucide-react'
import { ButtonLink } from '@/components/ui/button'
import { Container } from '@/components/ui/layout'
import { Metric } from '@/components/ui/metric'

/**
 * Split header with a visual panel
 *
 * Copy on the left, a live component composition on the right. The right panel
 * is real UI rather than a screenshot, which is both more honest and more
 * useful: it stays correct when the theme changes.
 *
 * Below `lg` the panel moves below the copy rather than shrinking, because a
 * squeezed dashboard preview communicates nothing.
 */
export default function SplitVisualHeader() {
  return (
    <header className="overflow-hidden border-b border-line bg-canvas py-section">
      <Container>
        <div className="grid items-center gap-12 lg:grid-cols-2 lg:gap-16">
          <div>
            <p className="label-caps text-accent">Built for product teams</p>
            <h1 className="display-type mt-4 text-3xl leading-tight font-semibold text-ink-strong sm:text-4xl lg:text-5xl">
              One system. Every surface in your product.
            </h1>
            <p className="mt-5 max-w-lg text-md text-ink-muted">
              Density is a theme axis, not a table prop — so your admin console and your marketing
              site can finally share a component set.
            </p>
            <div className="mt-8 flex flex-wrap gap-3">
              <ButtonLink href="/components" trailingIcon={<ArrowRight className="size-4" />}>
                Explore components
              </ButtonLink>
              <ButtonLink href="/docs/design-tokens" variant="outline">
                See the tokens
              </ButtonLink>
            </div>
          </div>

          <div className="relative">
            <div
              className="grid-paper absolute -inset-6 rounded-xl opacity-60"
              aria-hidden="true"
            />
            <div className="relative rounded-xl border border-line bg-surface p-5 shadow-lg">
              <div className="flex items-center justify-between">
                <p className="text-sm font-semibold text-ink-strong">Workspace overview</p>
                <p className="label-caps text-ink-subtle">Last 30 days</p>
              </div>
              <div className="mt-4 grid grid-cols-2 gap-3">
                <Metric
                  label="Active seats"
                  value="1,284"
                  delta={4.1}
                  sparkline={[40, 42, 41, 45, 47, 49, 52, 54]}
                />
                <Metric
                  label="p95 latency"
                  value="182 ms"
                  delta={-8.3}
                  invertTrend
                  sparkline={[30, 28, 31, 26, 24, 22, 20, 18]}
                />
              </div>
              <div className="mt-3 rounded-lg border border-line bg-surface-sunken p-3">
                <p className="label-caps text-ink-subtle">Deployment</p>
                <p className="mt-1 text-sm text-ink">
                  <span className="font-medium text-ink-strong">v1.4.2</span> shipped to EU West
                </p>
              </div>
            </div>
          </div>
        </div>
      </Container>
    </header>
  )
}

import type { ReactNode } from 'react'
import { ArrowUpRight, ArrowDownRight, Minus } from 'lucide-react'
import { cn } from '@/lib/cn'

/**
 * Metric
 *
 * A single number with optional trend. The delta carries an arrow *and* a sign
 * *and* a colour, so the direction survives a greyscale print or a colour
 * vision deficiency.
 *
 * `<dl>` semantics pair the label with the value; the sparkline is decorative
 * and hidden from assistive tech, since the number beside it is the content.
 */
export interface MetricProps {
  label: string
  value: string
  /** Percentage change. Positive is not automatically "good" — see `invertTrend`. */
  delta?: number
  deltaLabel?: string
  /** For metrics where down is good, e.g. churn or latency. */
  invertTrend?: boolean
  icon?: ReactNode
  /** 0–1 values rendered as a decorative sparkline. */
  sparkline?: number[]
  appearance?: 'plain' | 'card'
  className?: string
}

function Sparkline({ points }: { points: number[] }) {
  if (points.length < 2) return null
  const max = Math.max(...points)
  const min = Math.min(...points)
  const range = max - min || 1
  const path = points
    .map((point, index) => {
      const x = (index / (points.length - 1)) * 100
      const y = 28 - ((point - min) / range) * 26 - 1
      return `${index === 0 ? 'M' : 'L'}${x.toFixed(2)},${y.toFixed(2)}`
    })
    .join(' ')

  return (
    <svg viewBox="0 0 100 28" preserveAspectRatio="none" className="h-7 w-full" aria-hidden="true">
      <path
        d={path}
        fill="none"
        stroke="var(--color-accent)"
        strokeWidth="1.5"
        vectorEffect="non-scaling-stroke"
      />
    </svg>
  )
}

export function Metric({
  label,
  value,
  delta,
  deltaLabel,
  invertTrend = false,
  icon,
  sparkline,
  appearance = 'card',
  className,
}: MetricProps) {
  const direction = delta === undefined ? 'flat' : delta > 0 ? 'up' : delta < 0 ? 'down' : 'flat'
  const good = direction === 'flat' ? null : invertTrend ? direction === 'down' : direction === 'up'
  const TrendIcon =
    direction === 'up' ? ArrowUpRight : direction === 'down' ? ArrowDownRight : Minus

  return (
    <dl
      className={cn(
        'flex min-w-0 flex-col gap-1',
        appearance === 'card' && 'rounded-lg border border-line bg-surface p-card',
        className,
      )}
    >
      <div className="flex items-center justify-between gap-2">
        <dt className="label-caps truncate text-ink-subtle">{label}</dt>
        {icon ? <span className="shrink-0 text-ink-subtle">{icon}</span> : null}
      </div>
      <dd className="display-type text-2xl leading-none font-semibold text-ink-strong tabular-nums">
        {value}
      </dd>
      {delta !== undefined ? (
        <dd
          className={cn(
            'flex items-center gap-1 text-xs font-medium',
            good === null ? 'text-ink-muted' : good ? 'text-success' : 'text-danger',
          )}
        >
          <TrendIcon className="size-3.5 shrink-0" aria-hidden="true" />
          <span>
            {delta > 0 ? '+' : ''}
            {delta}%
          </span>
          {deltaLabel ? <span className="text-ink-subtle">{deltaLabel}</span> : null}
        </dd>
      ) : null}
      {sparkline ? (
        <dd className="mt-1">
          <Sparkline points={sparkline} />
        </dd>
      ) : null}
    </dl>
  )
}