:root {
    --primary-color: #3498db;
    --secondary-color: #f8f9fa;
    --text-color: #333;
    --light-text: #777;
    --border-color: #ddd;
    --white: #fff;
    --light-gray: #f5f5f5;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

body {
    background-color: #f5f7fa;
    color: var(--text-color);
    line-height: 1.6;
}

.container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 20px;
}

header {
    text-align: center;
    margin-bottom: 30px;
}

header h1 {
    color: var(--primary-color);
    font-size: 2.5rem;
    margin-bottom: 10px;
}

header p {
    color: var(--light-text);
    font-size: 1.1rem;
}

.app-container {
    display: flex;
    gap: 20px;
}

.sidebar {
    width: 300px;
    background-color: var(--white);
    border-radius: 8px;
    padding: 20px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
}

.main-content {
    flex: 1;
    background-color: var(--white);
    border-radius: 8px;
    padding: 20px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
}

.sidebar-section {
    margin-bottom: 25px;
}

.sidebar-section h3 {
    font-size: 1.1rem;
    margin-bottom: 15px;
    color: var(--primary-color);
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 8px;
}

.template-select {
    width: 100%;
    padding: 10px;
    border: 1px solid var(--border-color);
    border-radius: 5px;
    font-size: 0.9rem;
    margin-bottom: 15px;
}

.color-selector {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
}

.color-option {
    width: 30px;
    height: 30px;
    border-radius: 50%;
    cursor: pointer;
    border: 2px solid transparent;
    transition: all 0.3s ease;
}

.color-option:hover {
    transform: scale(1.1);
}

.color-option.active {
    border-color: var(--text-color);
}

.blue { background-color: #3498db; }
.green { background-color: #2ecc71; }
.purple { background-color: #9b59b6; }
.orange { background-color: #e67e22; }

.saved-invoices {
    max-height: 200px;
    overflow-y: auto;
}

.saved-invoice {
    padding: 10px;
    margin-bottom: 8px;
    background-color: var(--light-gray);
    border-radius: 5px;
    cursor: pointer;
    transition: all 0.3s ease;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.saved-invoice:hover {
    background-color: var(--border-color);
}

.saved-invoice .invoice-name {
    font-weight: 500;
}

.saved-invoice .invoice-date {
    font-size: 0.8rem;
    color: var(--light-text);
}

.delete-invoice {
    color: var(--danger-color);
    background: none;
    border: none;
    cursor: pointer;
    font-size: 0.9rem;
}

.invoice-controls {
    display: flex;
    gap: 10px;
    margin-bottom: 20px;
}

.btn {
    padding: 10px 15px;
    background-color: var(--primary-color);
    color: white;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    transition: all 0.3s ease;
    display: inline-flex;
    align-items: center;
    gap: 5px;
    font-size: 0.9rem;
}

.btn:hover {
    opacity: 0.9;
    transform: translateY(-2px);
}

.form-section {
    margin-bottom: 25px;
    padding-bottom: 15px;
    border-bottom: 1px solid var(--border-color);
}

.form-section h3 {
    margin-bottom: 15px;
    color: var(--primary-color);
}

.form-row {
    display: flex;
    gap: 15px;
    margin-bottom: 15px;
}

.form-group {
    flex: 1;
}

.form-group label {
    display: block;
    margin-bottom: 5px;
    font-weight: 500;
    font-size: 0.9rem;
}

.form-group input,
.form-group textarea,
.form-group select {
    width: 100%;
    padding: 10px;
    border: 1px solid var(--border-color);
    border-radius: 5px;
    font-size: 0.9rem;
}

.form-group textarea {
    resize: vertical;
    min-height: 60px;
}

.items-table-container {
    overflow-x: auto;
}

.items-table {
    width: 100%;
    border-collapse: collapse;
    margin-bottom: 15px;
}

.items-table th {
    background-color: var(--primary-color);
    color: white;
    padding: 10px;
    text-align: left;
}

.items-table td {
    padding: 10px;
    border-bottom: 1px solid var(--border-color);
    vertical-align: middle;
}

.items-table input {
    width: 100%;
    padding: 8px;
    border: 1px solid var(--border-color);
    border-radius: 3px;
}

.item-amount {
    font-weight: 500;
}

.remove-item-btn {
    background: none;
    border: none;
    color: var(--danger-color);
    cursor: pointer;
    font-size: 1rem;
}

.summary-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 10px;
    max-width: 500px;
}

.summary-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 8px 0;
    border-bottom: 1px dashed var(--border-color);
}

.summary-row span:first-child {
    font-weight: 500;
}

.summary-row span:last-child {
    font-weight: 600;
}

.input-group {
    display: flex;
    align-items: center;
    gap: 5px;
}

.input-group input {
    width: 80px;
    padding: 8px;
    border: 1px solid var(--border-color);
    border-radius: 3px;
}

.grand-total {
    font-size: 1.1rem;
    color: var(--primary-color);
    font-weight: 600;
    margin-top: 10px;
    padding-top: 10px;
    border-top: 2px solid var(--primary-color);
}

.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.5);
    z-index: 1000;
    overflow-y: auto;
    padding: 20px;
}

.modal-content {
    background-color: white;
    margin: 0 auto;
    max-width: 800px;
    border-radius: 8px;
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.2);
}

.modal-header {
    padding: 15px 20px;
    border-bottom: 1px solid var(--border-color);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.modal-header h2 {
    color: var(--primary-color);
}

.close-modal {
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
    color: var(--light-text);
}

.modal-body {
    padding: 20px;
}

.modal-footer {
    padding: 15px 20px;
    border-top: 1px solid var(--border-color);
    display: flex;
    justify-content: flex-end;
    gap: 10px;
}

/* Invoice Template Styles */
.invoice-template {
    background-color: white;
    padding: 30px;
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
    width: 210mm; /* A4 width */
    min-height: 297mm; /* A4 height */
    margin: 0 auto;
}

.invoice-header {
    display: flex;
    justify-content: space-between;
    margin-bottom: 30px;
}

.invoice-title {
    font-size: 1.8rem;
    color: var(--primary-color);
    margin-bottom: 5px;
}

.invoice-logo {
    max-width: 150px;
    max-height: 80px;
}

.invoice-meta {
    margin-bottom: 30px;
    display: flex;
    justify-content: space-between;
}

.invoice-company,
.invoice-customer {
    flex: 1;
}

.invoice-company h3,
.invoice-customer h3 {
    margin-bottom: 10px;
    color: var(--primary-color);
    font-size: 1.1rem;
}

.invoice-details {
    display: flex;
    gap: 20px;
    margin-top: 10px;
}

.invoice-details div {
    flex: 1;
}

.invoice-details span {
    display: block;
    margin-bottom: 5px;
}

.invoice-details span:first-child {
    font-weight: 500;
    color: var(--light-text);
    font-size: 0.9rem;
}

.invoice-items {
    width: 100%;
    border-collapse: collapse;
    margin-bottom: 30px;
}

.invoice-items th {
    background-color: var(--primary-color);
    color: white;
    padding: 10px;
    text-align: left;
}

.invoice-items td {
    padding: 12px 10px;
    border-bottom: 1px solid var(--border-color);
}

.invoice-items tr:last-child td {
    border-bottom: none;
}

.invoice-totals {
    display: flex;
    justify-content: flex-end;
}

.invoice-totals table {
    width: 300px;
    border-collapse: collapse;
}

.invoice-totals td {
    padding: 8px 10px;
    border-bottom: 1px dashed var(--border-color);
}

.invoice-totals tr:last-child td {
    border-bottom: none;
    font-weight: 600;
    color: var(--primary-color);
    font-size: 1.1rem;
}

.invoice-footer {
    margin-top: 40px;
    padding-top: 20px;
    border-top: 1px solid var(--border-color);
    text-align: center;
    font-size: 0.9rem;
    color: var(--light-text);
}

.invoice-notes {
    margin-top: 20px;
    padding: 15px;
    background-color: var(--light-gray);
    border-radius: 5px;
}

.invoice-notes h4 {
    margin-bottom: 10px;
    color: var(--primary-color);
}

.qr-code-container {
    margin-top: 20px;
    display: flex;
    justify-content: center;
}

/* Template specific styles */
.classic .invoice-header {
    border-bottom: 2px solid var(--primary-color);
    padding-bottom: 20px;
}

.stylish .invoice-title {
    border-left: 5px solid var(--primary-color);
    padding-left: 15px;
}

.elegant .invoice-header {
    background-color: var(--primary-color);
    color: white;
    padding: 20px;
    border-radius: 5px;
    margin-bottom: 20px;
}

.elegant .invoice-title {
    color: white;
}

.modern .invoice-items th {
    background-color: transparent;
    color: var(--primary-color);
    border-bottom: 2px solid var(--primary-color);
}

/* Responsive styles */
@media (max-width: 992px) {
    .app-container {
        flex-direction: column;
    }

    .sidebar {
        width: 100%;
        margin-bottom: 20px;
    }
}

@media (max-width: 768px) {
    .form-row {
        flex-direction: column;
        gap: 15px;
    }

    .invoice-meta {
        flex-direction: column;
        gap: 20px;
    }

    .invoice-details {
        flex-direction: column;
        gap: 10px;
    }

    .summary-grid {
        grid-template-columns: 1fr;
    }
}

@media print {
    body * {
        visibility: hidden;
    }
    #invoicePreview, #invoicePreview * {
        visibility: visible;
    }
    #invoicePreview {
        position: absolute;
        left: 0;
        top: 0;
        width: 100%;
        margin: 0;
        padding: 0;
    }
    .invoice-template {
        box-shadow: none;
        padding: 0;
        width: 100%;
        min-height: 100%;
    }
    .modal-header, .modal-footer {
        display: none;
    }
}