body {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  background-color: #f4f6f9;
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 100vh;
  margin: 0;
}

.card {
  background: white;
  padding: 2rem;
  border-radius: 16px;
  box-shadow: 0 4px 20px rgba(0,0,0,0.1);
  text-align: center;
  width: 90%;
  max-width: 360px;
}

h2 { margin-bottom: 0.5rem; color: #1e293b; }
p { color: #64748b; font-size: 0.9rem; margin-bottom: 1.5rem; }

#qrcode {
  display: flex;
  justify-content: center;
  margin: 1rem 0;
  min-height: 200px;
  align-items: center;
}

#qrcode canvas, #qrcode img {
  border-radius: 8px;
  border: 4px solid #f1f5f9;
}

.qr-error {
  max-width: 260px;
  color: #b91c1c;
  font-size: 0.9rem;
}

.timer-container {
  margin-top: 1rem;
  background: #e2e8f0;
  border-radius: 8px;
  height: 8px;
  overflow: hidden;
}

.timer-bar {
  height: 100%;
  background: #2563eb;
  width: 100%;
  transition: width 1s linear;
}

.code-text {
  font-size: 1.2rem;
  font-weight: bold;
  letter-spacing: 2px;
  color: #0f172a;
  margin-top: 0.5rem;
}