body {
  font-family: Arial, sans-serif;
  background: #f4f6fb;
}

.main {
  min-height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
}

.card {
  background: #fff;
  padding: 24px;
  border-radius: 12px;
  width: 320px;
  text-align: center;
}

.qr {
  width: 240px;
  margin: 16px 0;
}

button {
  width: 100%;
  padding: 12px;
  margin-top: 12px;
}

.hint {
  font-size: 13px;
  color: #666;
}