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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto',
    'Oxygen', 'Ubuntu', 'Cantarell', 'Fira Sans', 'Droid Sans',
    'Helvetica Neue', sans-serif;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    background-color: #f8f9fa;
    color: #333;
    line-height: 1.6;
    min-height: 100vh;
    padding: 20px 0;
}

.container {
    max-width: 800px;
    margin: 0 auto;
    padding: 20px;
}

header {
    text-align: center;
    margin-bottom: 40px;
}

header h1 {
    color: #333;
    margin-bottom: 10px;
}

header p {
    color: #666;
    font-size: 16px;
}

.products h2 {
    margin-bottom: 20px;
    color: #333;
}

.product-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 20px;
    margin-bottom: 40px;
}

.product-card {
    border: 1px solid #ddd;
    border-radius: 8px;
    padding: 20px;
    text-align: center;
    transition: transform 0.2s, box-shadow 0.2s;
    background: white;
}

.product-card:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0,0,0,0.1);
}

.product-card h3 {
    margin: 0 0 10px 0;
    color: #333;
}

.description {
    color: #666;
    margin-bottom: 15px;
    font-size: 14px;
}

.price {
    font-size: 24px;
    font-weight: bold;
    color: #0570de;
    margin-bottom: 15px;
}

.select-btn {
    background: #0570de;
    color: white;
    border: none;
    padding: 12px 24px;
    border-radius: 4px;
    cursor: pointer;
    font-size: 16px;
    transition: background 0.2s;
}

.select-btn:hover:not(:disabled) {
    background: #0458b3;
}

.select-btn:disabled {
    background: #ccc;
    cursor: not-allowed;
}

.checkout {
    max-width: 500px;
    margin: 0 auto;
}

.order-summary {
    background: white;
    padding: 20px;
    border-radius: 8px;
    margin-bottom: 30px;
    border: 1px solid #ddd;
}

.order-summary h2 {
    margin: 0 0 15px 0;
    color: #333;
}

.order-details p {
    margin: 8px 0;
    color: #555;
}

.back-btn {
    background: #6c757d;
    color: white;
    border: none;
    padding: 10px 20px;
    border-radius: 4px;
    cursor: pointer;
    margin-top: 20px;
    font-size: 14px;
}

.back-btn:hover {
    background: #5a6268;
}

/* Payment Form Styles */
.payment-form {
    max-width: 500px;
    margin: 0 auto;
}

.payment-section {
    margin-bottom: 30px;
    background: white;
    padding: 20px;
    border-radius: 8px;
    border: 1px solid #ddd;
}

.payment-section h3 {
    margin: 0 0 15px 0;
    color: #333;
    font-size: 18px;
}

.pay-button {
    width: 100%;
    background: #0570de;
    color: white;
    border: none;
    padding: 16px;
    border-radius: 4px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: background 0.2s;
    margin-top: 20px;
}

.pay-button:hover:not(:disabled) {
    background: #0458b3;
}

.pay-button:disabled {
    background: #ccc;
    cursor: not-allowed;
}

.spinner {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
}

.spinner-border {
    width: 20px;
    height: 20px;
    border: 2px solid transparent;
    border-top: 2px solid white;
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

.message {
    margin-top: 15px;
    padding: 12px;
    border-radius: 4px;
    text-align: center;
}

.message.success {
    background: #d4edda;
    color: #155724;
    border: 1px solid #c3e6cb;
}

.message.error {
    background: #f8d7da;
    color: #721c24;
    border: 1px solid #f5c6cb;
}

.success-container {
    text-align: center;
    padding: 40px 20px;
}

.success-message {
    background: #d4edda;
    color: #155724;
    padding: 30px;
    border: 1px solid #c3e6cb;
    border-radius: 8px;
}

.success-message h2 {
    margin: 0 0 15px 0;
    color: #155724;
}

.success-message p {
    margin: 10px 0;
}