* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  min-height: 100vh;
  padding: 20px;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
}

.payment-card {
  background: white;
  padding: 40px;
  border-radius: 10px;
  box-shadow: 0 4px 6px rgba(0,0,0,0.1);
  max-width: 600px;
  margin: 50px auto;
}

h1 {
  color: #333;
  text-align: center;
  margin-bottom: 10px;
}

.subtitle {
  text-align: center;
  color: #666;
  margin-bottom: 30px;
}

.payment-form {
  margin-top: 30px;
}

.form-group {
  margin-bottom: 20px;
}

.form-group label {
  display: block;
  margin-bottom: 8px;
  color: #333;
  font-weight: 600;
}

.form-group input {
  width: 100%;
  padding: 12px;
  border: 2px solid #e0e0e0;
  border-radius: 5px;
  font-size: 16px;
  transition: border-color 0.3s;
}

.form-group input:focus {
  outline: none;
  border-color: #667eea;
}

.btn-pay {
  width: 100%;
  padding: 15px;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
  border: none;
  border-radius: 5px;
  font-size: 18px;
  font-weight: 600;
  cursor: pointer;
  transition: transform 0.2s;
  text-decoration: none;
  display: inline-block;
  text-align: center;
}

.btn-pay:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 8px rgba(0,0,0,0.2);
}

.info-section {
  margin-top: 30px;
  padding-top: 30px;
  border-top: 2px solid #e0e0e0;
}

.info-section h3 {
  color: #333;
  margin-bottom: 10px;
}

.info-section p {
  color: #666;
  margin-bottom: 10px;
}

.info-section code {
  display: block;
  background: #f5f5f5;
  padding: 15px;
  border-radius: 5px;
  font-size: 14px;
  overflow-x: auto;
  word-wrap: break-word;
}

.transaction-details {
  margin: 20px 0;
  background: #f9f9f9;
  padding: 20px;
  border-radius: 5px;
}

h2 {
  color: #333;
  margin: 30px 0 20px 0;
  font-size: 24px;
}

@media (max-width: 768px) {
  .payment-card {
    padding: 20px;
  }
  
  .container {
    padding: 10px;
  }
  
  h1 {
    font-size: 24px;
  }
}