// Genera un degradado determinista a partir de la semilla; sin dependencias de red.
function hash(s: string): number {
  let h = 0
  for (let i = 0; i < s.length; i++) h = (h * 31 + s.charCodeAt(i)) >>> 0
  return h
}

export function Thumb({ seed, className = '' }: { seed: string; className?: string }) {
  const h = hash(seed)
  const hue = h % 360
  const hue2 = (hue + 40) % 360
  return (
    <div
      className={`relative overflow-hidden ${className}`}
      style={{ background: `linear-gradient(135deg, hsl(${hue} 45% 28%), hsl(${hue2} 40% 16%))` }}
      aria-hidden
    >
      <div
        className="absolute inset-0 opacity-30"
        style={{ backgroundImage: 'radial-gradient(circle at 30% 20%, rgba(255,255,255,.25), transparent 40%)' }}
      />
    </div>
  )
}