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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: #0a0a0a;
    color: #e0e0e0;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Header */
header {
    padding: 20px 0;
    border-bottom: 1px solid #1a1a1a;
    background: #0a0a0a;
}

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: #fff;
    text-decoration: none;
}

.tagline {
    color: #666;
    font-size: 0.9rem;
    margin-top: 4px;
}

/* Products Grid */
main {
    flex: 1;
    padding: 40px 0;
}

.products-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 24px;
}

.product-card {
    background: #141414;
    border: 1px solid #222;
    border-radius: 12px;
    overflow: hidden;
    transition: transform 0.2s, border-color 0.2s;
}

.product-card:hover {
    transform: translateY(-4px);
    border-color: #333;
}

.product-image {
    width: 100%;
    height: 200px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: #1a1a1a;
    padding: 20px;
}

.product-image img {
    max-width: 120px;
    max-height: 120px;
    opacity: 0.8;
}

.product-info {
    padding: 20px;
}

.product-info h3 {
    font-size: 1rem;
    color: #fff;
    margin-bottom: 8px;
}

.product-info .desc {
    font-size: 0.85rem;
    color: #888;
    margin-bottom: 16px;
}

.product-info .price {
    font-size: 1.25rem;
    font-weight: 700;
    color: #4ade80;
    margin-bottom: 16px;
}

.btn-buy {
    display: block;
    width: 100%;
    padding: 12px;
    background: #fff;
    color: #000;
    border: none;
    border-radius: 8px;
    font-size: 0.9rem;
    font-weight: 600;
    cursor: pointer;
    transition: background 0.2s;
}

.btn-buy:hover {
    background: #e0e0e0;
}

/* Checkout */
.checkout-box {
    max-width: 500px;
    margin: 0 auto;
    background: #141414;
    border: 1px solid #222;
    border-radius: 16px;
    padding: 40px;
}

.checkout-box h2 {
    font-size: 1.5rem;
    margin-bottom: 24px;
    color: #fff;
}

.order-item {
    display: flex;
    gap: 16px;
    padding: 16px;
    background: #1a1a1a;
    border-radius: 8px;
    margin-bottom: 24px;
}

.order-item img {
    width: 60px;
    height: 60px;
    object-fit: contain;
    opacity: 0.8;
}

.order-info h3 {
    font-size: 0.95rem;
    color: #fff;
    margin-bottom: 4px;
}

.order-info p {
    font-size: 0.85rem;
    color: #888;
}

.order-info .price {
    color: #4ade80;
    font-weight: 700;
    font-size: 1.1rem;
    margin-top: 4px;
}

.form-group {
    margin-bottom: 24px;
}

.form-group label {
    display: block;
    font-size: 0.9rem;
    color: #ccc;
    margin-bottom: 8px;
}

.form-group input {
    width: 100%;
    padding: 14px 16px;
    background: #1a1a1a;
    border: 1px solid #333;
    border-radius: 8px;
    color: #fff;
    font-size: 1rem;
    outline: none;
    transition: border-color 0.2s;
}

.form-group input:focus {
    border-color: #4ade80;
}

.form-group small {
    display: block;
    margin-top: 6px;
    color: #666;
    font-size: 0.8rem;
}

.btn-pay {
    display: block;
    width: 100%;
    padding: 16px;
    background: #4ade80;
    color: #000;
    border: none;
    border-radius: 8px;
    font-size: 1rem;
    font-weight: 700;
    cursor: pointer;
    transition: background 0.2s;
}

.btn-pay:hover {
    background: #22c55e;
}

.btn-pay:disabled {
    background: #333;
    color: #666;
    cursor: not-allowed;
}

.pay-note {
    text-align: center;
    color: #666;
    font-size: 0.8rem;
    margin-top: 12px;
}

/* Success */
.success-box {
    max-width: 500px;
    margin: 0 auto;
    text-align: center;
    background: #141414;
    border: 1px solid #222;
    border-radius: 16px;
    padding: 60px 40px;
}

.success-icon {
    font-size: 4rem;
    margin-bottom: 20px;
}

.success-box h2 {
    color: #4ade80;
    font-size: 1.8rem;
    margin-bottom: 12px;
}

.success-box > p {
    color: #888;
    margin-bottom: 24px;
}

.order-detail {
    background: #1a1a1a;
    border-radius: 8px;
    padding: 16px;
    margin-bottom: 24px;
}

.order-detail p {
    color: #ccc;
    margin: 8px 0;
}

.status-paid {
    color: #4ade80;
    font-weight: 600;
}

.btn-back {
    display: inline-block;
    padding: 12px 32px;
    background: #fff;
    color: #000;
    text-decoration: none;
    border-radius: 8px;
    font-weight: 600;
    transition: background 0.2s;
}

.btn-back:hover {
    background: #e0e0e0;
}

/* Footer */
footer {
    padding: 20px 0;
    border-top: 1px solid #1a1a1a;
    text-align: center;
    color: #444;
    font-size: 0.85rem;
}

/* Responsive */
@media (max-width: 768px) {
    .products-grid {
        grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
        gap: 16px;
    }

    .checkout-box {
        padding: 24px;
    }
}

@media (max-width: 480px) {
    .products-grid {
        grid-template-columns: 1fr;
    }
}