.checkout-container { 
    max-width: 800px; 
    margin: 40px auto; 
    padding: 0 20px; 
    display: flex; 
    gap: 30px; 
}

.checkout-form { 
    flex: 2; 
}

.checkout-summary { 
    flex: 1; 
    background: #f9f9f9; 
    padding: 25px; 
    height: fit-content; 
    border: 1px solid #eee; 
    border-radius: 4px; 
}

.section-box { 
    border: 1px solid #ddd; 
    padding: 20px; 
    margin-bottom: 20px; 
    border-radius: 4px; 
    background: #fff; 
}

.section-title { 
    font-size: 16px; 
    text-transform: uppercase; 
    letter-spacing: 1px; 
    margin-bottom: 15px; 
    border-bottom: 1px solid #eee; 
    padding-bottom: 10px; 
}

.form-group { 
    margin-bottom: 15px; 
}

.form-group label { 
    display: block; 
    margin-bottom: 8px; 
    font-size: 13px; 
    font-weight: 600; 
    color: #555; 
}

.form-group input, 
.form-group select, 
.form-group textarea { 
    width: 100%; 
    padding: 12px; 
    border: 1px solid #ccc; 
    border-radius: 4px; 
    box-sizing: border-box; 
    font-family: inherit; 
}

.radio-group { 
    display: flex; 
    gap: 15px; 
    margin-bottom: 15px; 
}

.radio-box { 
    flex: 1; 
    border: 1px solid #ddd; 
    padding: 15px; 
    cursor: pointer; 
    text-align: center; 
    border-radius: 4px; 
    transition: 0.3s; 
}

.radio-box.active { 
    border-color: #000; 
    background: #fafafa; 
    font-weight: bold; 
}

.summary-item { 
    display: flex; 
    justify-content: space-between; 
    margin-bottom: 10px; 
    font-size: 14px; 
}

.summary-total { 
    display: flex; 
    justify-content: space-between; 
    margin-top: 15px; 
    padding-top: 15px; 
    border-top: 2px solid #ddd; 
    font-weight: bold; 
    font-size: 18px; 
}

.btn-confirm { 
    background: #000; 
    color: #fff; 
    border: none; 
    padding: 15px; 
    width: 100%; 
    cursor: pointer; 
    font-size: 14px; 
    text-transform: uppercase; 
    letter-spacing: 1px; 
    margin-top: 20px; 
    transition: 0.3s; 
}

.btn-confirm:hover { 
    background: #333; 
}

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

.payment-detail-box { 
    display: none; 
    padding: 15px; 
    margin-top: 10px; 
    border-radius: 4px; 
    animation: fadeIn 0.3s ease; 
}

@keyframes fadeIn { 
    from { opacity: 0; transform: translateY(-5px); } 
    to { opacity: 1; transform: translateY(0); } 
}