body {
    background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%) fixed;
    min-height: 100vh;
}
.payment-container {
    max-width: 650px;
    margin: 0 auto;
    padding: 30px 15px;
}
.payment-card {
    background: white !important;
    border-radius: 25px;
    box-shadow: 0 10px 40px rgba(0,0,0,0.08);
    overflow: hidden;
    border: none;
    margin-top: 30px;
}
.payment-header {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    padding: 15px;
    text-align: center;
    color: white;
    height: 35px;
}
.payment-logo {
    width: 120px;
    height: auto;
    margin-bottom: 10px;
    background: white;
    padding: 8px;
    border-radius: 8px;
}
.merchant-name {
    font-size: 22px;
    font-weight: 600;
    margin: 15px 0 30px;
    text-align: center;
}
.product-name {
    font-size: 20px;
    font-weight: 600;
    margin: 0 0 25px;
    text-align: center;
    color: #1e293b;
}
.confirmation-badge {
    display: inline-block;
    background: rgba(255,255,255,0.2);
    padding: 6px 20px;
    border-radius: 20px;
    font-size: 13px;
    font-weight: 500;
    letter-spacing: 0.5px;
    margin-top: 8px;
}
.payment-body {
    padding: 15px 20px 30px;
}
.card{
    box-shadow: 0 10px 40px rgba(0,0,0,0.08);
    border-radius: 15px;
}
.card-body{
    padding: 20px;
}
.payment-details {
    background: white;
    border-radius: 12px;
    padding: 20px;
    margin-bottom: 20px;
    border: 2px solid #e2e8f0;
}
.detail-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 8px 0;
}
.detail-label {
    font-size: 14px;
    color: #64748b;
    font-weight: 500;
}
.detail-value {
    font-size: 15px;
    color: #1e293b;
    font-weight: 600;
}
.detail-divider {
    border: none;
    border-top: 1px solid #e2e8f0;
    margin: 12px 0;
}
.detail-row:first-child {
    padding-top: 0;
}
.detail-row.with-border {
    padding-bottom: 0;
    border-top: 1.5px solid #e2e8f0;
    margin-top: 10px;
    padding-top: 15px;
}
.invoice-title {
    font-size: 22px;
    font-weight: 600;
    margin: 15px 0 5px;
    text-align: center;
}
.invoice-number {
    font-size: 17px;
    color: #64748b;
    margin: 0 0 25px;
    text-align: center;
}
.success-alert {
    background: #d1fae5;
    border: 1px solid #6ee7b7;
    border-radius: 10px;
    padding: 15px;
    margin-bottom: 20px;
    text-align: center;
}
.success-alert h4 {
    color: #059669;
    font-size: 16px;
    font-weight: 600;
    margin: 0;
}
.payment-card * {
    background-color: transparent;
}
.payment-card .payment-header,
.payment-card .payment-details,
.payment-card .invoice-note,
.payment-card .success-alert,
.payment-card .secure-badge,
.payment-card .form-control,
.payment-card .form-select {
    background-color: initial;
}
.total-row {
    padding: 12px 0 0 0;
}
.total-row .detail-label {
    font-size: 16px;
    color: #1e293b;
    font-weight: 600;
}
.total-row .detail-value {
    font-size: 24px;
    color: #dc2626;
    font-weight: 700;
}
.btn-submit {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border: none;
    border-radius: 10px;
    padding: 14px;
    font-size: 16px;
    font-weight: 600;
    color: white;
    width: 100%;
    transition: all 0.3s ease;
    box-shadow: 0 4px 15px rgba(102, 126, 234, 0.3);
}
.btn-submit:hover:not(:disabled) {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(102, 126, 234, 0.4);
    color: white;
}
.btn-submit:disabled {
    opacity: 0.5;
    cursor: not-allowed;
    background: #94a3b8;
}
.secure-badge {
    background: linear-gradient(135deg, #f8fafc 0%, #e2e8f0 100%);
    padding: 15px;
    text-align: center;
    border-top: 1px solid #e2e8f0;
}
.secure-badge i {
    color: #667eea;
    margin-right: 5px;
    font-size: 16px;
}
.secure-text {
    font-size: 14px;
    font-weight: 600;
    color: #475569;
    margin: 0;
}
.paying-label {
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    margin-bottom: 20px;
}
.paying-label::before,
.paying-label::after {
    content: '';
    width: 50px;
    border-bottom: 1px solid #e2e8f0;
    opacity: 0.5;
}
.paying-label::before {
    margin-right: 12px;
}
.paying-label::after {
    margin-left: 12px;
}
.paying-label span {
    font-size: 14px;
    color: #64748b;
    font-weight: 500;
    white-space: nowrap;
}
.form-label {
    font-size: 13px;
    font-weight: 500;
    color: #475569;
    margin-bottom: 0px;
}


.receipt-drop-zone { border: 2px dashed #b3aaff; border-radius: 10px; padding: 20px 16px; text-align: center; background: #fafafe; cursor: pointer; }
.receipt-drop-zone:hover, .receipt-drop-zone.dragover { border-color: #6c5ce7; background: #f0edff; }
.receipt-upload-btn { background: #6c5ce7; color: #fff; border: none; border-radius: 6px; padding: 9px 20px; font-size: 14px; font-weight: 600; margin-bottom: 10px; cursor: pointer; }
.receipt-drop-text { color: #888; font-size: 13px; }
.receipt-drop-text .receipt-accent { color: #6c5ce7; font-weight: 600; }
.product-price {
    font-size: 23px;
    font-weight: 700;
    text-align: center;
    padding: 20px;
    background: white;
    border-radius: 10px;
    margin: 0 auto 25px;
    width: 200px;
    box-shadow: 1px 5px 11px 1px rgb(158 158 158 / 30%);
}
.section-title {
    font-size: 14px;
    font-weight: 600;
    color: #64748b;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin-bottom: 15px;
}
.amount-buttons {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 10px;
    margin-bottom: 15px;
}
.amount-btn {
    border: 2px solid #e2e8f0;
    background: #f8fafc;
    color: #1e293b;
    font-weight: 600;
    border-radius: 8px;
    padding: 6px 8px;
    transition: all 0.3s ease;
    font-size: 14px;
}
.amount-btn:hover, .amount-btn.active {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border-color: #667eea;
    color: white !important;
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(102, 126, 234, 0.3);
}
.form-control, .form-select {
    border-radius: 8px;
    border: 1.5px solid #e2e8f0;
    padding: 8px 14px;
    transition: all 0.3s ease;
}
.form-control:focus, .form-select:focus {
    border-color: #667eea;
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}
.form-group {
    margin-bottom: 0px !important;
    margin-top: 8px !important;
}
.total-section {
    background: #f8fafc;
    border-radius: 12px;
    padding: 20px;
    margin: 25px 0 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}
.total-label {
    font-size: 16px;
    font-weight: 600;
    color: #475569;
}
.total-value {
    font-size: 23px;
    font-weight: 700;
    color: #dc2626;
}


@media (max-width: 768px) {
    .payment-header {
        padding: 25px 15px;
    }
    .merchant-name {
        font-size: 18px;
    }
    .product-name {
        font-size: 18px;
    }
    .payment-body {
        padding: 15px 20px;
    }
    .invoice-title {
        font-size: 20px;
    }
    .total-row .detail-value {
        font-size: 20px;
    }
    .product-price {
        font-size: 28px;
    }
    .amount-buttons {
        gap: 8px;
    }
    .amount-btn {
        padding: 10px 6px;
        font-size: 12px;
    }
    .total-value {
        font-size: 22px;
    }
}
@media (max-width: 576px) {
    .payment-container {
        padding: 10px;
    }
    .payment-header {
        padding: 20px 15px;
    }
    .payment-logo {
        width: 100px;
    }
    .invoice-title {
        font-size: 18px;
    }
    .merchant-name {
        font-size: 16px;
    }
    .product-name {
        font-size: 16px;
    }
    .payment-body {
        padding: 10px 15px;
    }
    .payment-details {
        padding: 15px;
    }
    .detail-label, .detail-value {
        font-size: 13px;
    }
    .total-row .detail-value {
        font-size: 18px;
    }
    .product-price {
        font-size: 24px;
    }
    .amount-buttons {
        grid-template-columns: repeat(2, 1fr);
    }
    .total-section {
        flex-direction: column;
        text-align: center;
        gap: 8px;
    }
    .form-control, .form-select {
        padding: 8px 4px !important;
        padding-right: 0 !important;
        font-size: 14px;
    }
    .form-select {
        padding-right: 28px;
    }
    .form-label {
        font-size: 12px;
    }
}