body {
  font-family: system-ui, Arial;
  margin: 0;
  background: #0f172a;
  color: white;
}

header {
  text-align: center;
  padding: 80px 20px;
  background: linear-gradient(135deg, #2563eb, #9333ea);
}

main {
  max-width: 900px;
  margin: auto;
  padding: 40px 20px;
}

.card {
  background: #1e293b;
  padding: 25px;
  border-radius: 14px;
  margin-bottom: 20px;
}

footer {
  text-align: center;
  padding: 30px;
  opacity: 0.6;
}