:root {
    --primary-blue: #1e3c72;
    --secondary-blue: #2a5298;
    --accent-blue: #4a7dff;
    --light-blue: #f0f5ff;
    --lighter-blue: #f9fbff;
    --border-blue: #d0ddff;
    --text-dark: #333333;
    --text-medium: #555555;
    --text-light: #777777;
    --success-green: #28a745;
    --warning-orange: #ffc107;
    --error-red: #dc3545;
    --shadow-light: rgba(0, 0, 120, 0.08);
    --shadow-medium: rgba(0, 0, 120, 0.15);
    --star-color: #ffc107;
    --star-empty: #e0e0e0;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Segoe UI', 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
}

body {
    background-color: #f8fafc;
    color: var(--text-dark);
    line-height: 1.6;
    min-height: 100vh;
}

.app-container {
    display: flex;
    flex-direction: column;
    min-height: 100vh;
    max-width: 1800px;
    margin: 0 auto;
    position: relative;
}

/* Header */
.main-header {
    background: linear-gradient(135deg, var(--primary-blue) 0%, var(--secondary-blue) 100%);
    color: white;
    padding: 1.5rem 2rem;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    max-width: 100%;
}

.logo-section {
    display: flex;
    align-items: center;
}

.logo-icon {
    font-size: 2.5rem;
    margin-right: 1rem;
    background: rgba(255, 255, 255, 0.1);
    padding: 0.8rem;
    border-radius: 12px;
}

.logo-text h1 {
    font-size: 1.8rem;
    font-weight: 700;
    margin-bottom: 0.3rem;
}

.logo-text p {
    font-size: 0.95rem;
    opacity: 0.9;
}

.header-badge {
    background: rgba(255, 255, 255, 0.15);
    padding: 0.5rem 1rem;
    border-radius: 20px;
    font-size: 0.85rem;
    font-weight: 600;
}

/* Main Content */
.main-content {
    flex: 1;
    padding: 2rem;
    display: flex;
    flex-direction: column;
    gap: 2rem;
}

/* File Upload Section */
.upload-section {
    background: white;
    border-radius: 12px;
    box-shadow: 0 4px 16px var(--shadow-light);
    overflow: hidden;
}

.section-header {
    background: var(--lighter-blue);
    padding: 1.5rem 2rem;
    border-bottom: 1px solid var(--border-blue);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.section-header h2 {
    color: var(--primary-blue);
    font-size: 1.4rem;
    display: flex;
    align-items: center;
    gap: 0.8rem;
}

.section-header h2 i {
    color: var(--accent-blue);
}

.upload-container {
    padding: 3rem 2rem;
    text-align: center;
}

.upload-area {
    border: 3px dashed var(--accent-blue);
    border-radius: 12px;
    padding: 4rem 2rem;
    background: var(--lighter-blue);
    cursor: pointer;
    transition: all 0.3s ease;
    position: relative;
}

.upload-area:hover {
    background: #e8f1ff;
    border-color: var(--secondary-blue);
    transform: translateY(-2px);
    box-shadow: 0 8px 20px var(--shadow-medium);
}

.upload-area.drag-over {
    background: #e1ebff;
    border-color: var(--primary-blue);
    border-style: solid;
}

.upload-icon {
    font-size: 4rem;
    color: var(--accent-blue);
    margin-bottom: 1.5rem;
}

.upload-text {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--primary-blue);
    margin-bottom: 0.8rem;
}

.upload-subtext {
    color: var(--text-medium);
    margin-bottom: 1.5rem;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.upload-button {
    background: var(--accent-blue);
    color: white;
    border: none;
    padding: 1rem 2.5rem;
    border-radius: 8px;
    font-weight: 600;
    font-size: 1rem;
    cursor: pointer;
    transition: all 0.3s;
    display: inline-flex;
    align-items: center;
    gap: 0.8rem;
}

.upload-button:hover {
    background: var(--secondary-blue);
    transform: translateY(-2px);
    box-shadow: 0 6px 16px rgba(74, 125, 255, 0.3);
}

#fileInput {
    display: none;
}

/* Summary Cards */
.summary-section {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 1.5rem;
}

.summary-card {
    background: white;
    border-radius: 10px;
    padding: 1.8rem;
    box-shadow: 0 4px 12px var(--shadow-light);
    display: flex;
    align-items: center;
    gap: 1.2rem;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    border: 2px solid transparent;
}

.summary-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 20px var(--shadow-medium);
}

.card-icon {
    width: 60px;
    height: 60px;
    background: var(--light-blue);
    border-radius: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.8rem;
    color: var(--accent-blue);
}

.card-content {
    flex: 1;
}

.card-value {
    font-size: 2rem;
    font-weight: 700;
    color: var(--primary-blue);
    line-height: 1;
    margin-bottom: 0.3rem;
}

.card-label {
    color: var(--text-light);
    font-size: 0.95rem;
}

/* Control Buttons */
.controls-section {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
}

.btn {
    padding: 1rem 2rem;
    border-radius: 8px;
    font-weight: 600;
    font-size: 1rem;
    cursor: pointer;
    transition: all 0.3s;
    display: inline-flex;
    align-items: center;
    gap: 0.8rem;
    border: none;
}

.btn-primary {
    background: var(--accent-blue);
    color: white;
}

.btn-primary:hover:not(:disabled) {
    background: var(--secondary-blue);
    transform: translateY(-2px);
    box-shadow: 0 6px 16px rgba(74, 125, 255, 0.3);
}

.btn-secondary {
    background: white;
    color: var(--accent-blue);
    border: 2px solid var(--border-blue);
}

.btn-secondary:hover {
    background: var(--light-blue);
    border-color: var(--accent-blue);
}

.btn-success {
    background: var(--success-green);
    color: white;
}

.btn-success:hover:not(:disabled) {
    background: #218838;
    transform: translateY(-2px);
    box-shadow: 0 6px 16px rgba(40, 167, 69, 0.3);
}

.btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
}

.progress-bar {
    height: 4px;
    background: var(--border-blue);
    border-radius: 2px;
    overflow: hidden;
    margin-top: 1rem;
    width: 100%;
}

.progress-fill {
    height: 100%;
    background: var(--accent-blue);
    width: 0%;
    transition: width 0.3s ease;
}

/* Summary Report Table */
.summary-report {
    background: white;
    border-radius: 12px;
    box-shadow: 0 4px 16px var(--shadow-light);
    overflow: hidden;
}

.summary-report-table {
    width: 100%;
    border-collapse: collapse;
    table-layout: fixed;
}

.summary-report-table th {
    background: var(--secondary-blue);
    color: white;
    font-weight: 600;
    padding: 0.8rem 0.6rem;
    text-align: left;
    border-bottom: 2px solid var(--primary-blue);
    font-size: 0.9rem;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.summary-report-table th:nth-child(1),
.summary-report-table td:nth-child(1) {
    width: 20%;
    min-width: 180px;
    max-width: 250px;
}

.summary-report-table th:nth-child(2),
.summary-report-table td:nth-child(2) {
    width: 15%;
    min-width: 120px;
    max-width: 180px;
}

.summary-report-table th:nth-child(3),
.summary-report-table td:nth-child(3) {
    width: 25%;
    min-width: 220px;
    max-width: 350px;
}

.summary-report-table th:nth-child(4),
.summary-report-table td:nth-child(4),
.summary-report-table th:nth-child(5),
.summary-report-table td:nth-child(5) {
    width: 10%;
    min-width: 80px;
    max-width: 100px;
}

.summary-report-table th:nth-child(6),
.summary-report-table td:nth-child(6) {
    width: 20%;
    min-width: 100px;
    max-width: 150px;
}

.summary-report-table td {
    padding: 0.8rem 0.6rem;
    border-bottom: 1px solid #f1f3f5;
    border-right: 1px solid #f1f3f5;
    vertical-align: middle;
    word-wrap: break-word;
    overflow-wrap: break-word;
}

.summary-report-table tr:hover td {
    background: #f8fbff;
}

.summary-report-table tfoot td {
    background: var(--primary-blue);
    color: white;
    font-weight: 700;
    border: none;
    padding: 0.8rem 0.6rem;
}

.sheet-name-edit {
    padding: 0.4rem 0.6rem;
    border: 1px solid var(--border-blue);
    border-radius: 4px;
    width: 100%;
    font-size: 0.9rem;
    box-sizing: border-box;
}

.sheet-name-edit:focus {
    outline: none;
    border-color: var(--accent-blue);
    box-shadow: 0 0 0 2px rgba(74, 125, 255, 0.2);
}

/* Preview Section */
.preview-section {
    background: white;
    border-radius: 12px;
    box-shadow: 0 4px 16px var(--shadow-light);
    overflow: hidden;
    display: flex;
    flex-direction: column;
    flex: 1;
}

.preview-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1.2rem 1.5rem;
    background: var(--light-blue);
    border-bottom: 1px solid var(--border-blue);
}

.preview-header h3 {
    color: var(--primary-blue);
    font-size: 1.3rem;
    display: flex;
    align-items: center;
    gap: 0.8rem;
}

.sheet-selector {
    display: flex;
    align-items: center;
    gap: 0.8rem;
}

.sheet-selector label {
    color: var(--text-medium);
    font-weight: 600;
}

.sheet-select {
    padding: 0.6rem 1rem;
    border-radius: 6px;
    border: 1px solid var(--border-blue);
    background: white;
    color: var(--text-dark);
    font-weight: 500;
    min-width: 250px;
}

.preview-container {
    flex: 1;
    overflow: hidden;
    display: flex;
    flex-direction: column;
}

.preview-info-bar {
    padding: 0.8rem 1.5rem;
    background: #f8f9fa;
    border-bottom: 1px solid #e9ecef;
    font-size: 0.9rem;
    color: var(--text-medium);
    display: flex;
    justify-content: space-between;
}

.table-wrapper {
    flex: 1;
    overflow: auto;
    position: relative;
}

.preview-table {
    width: 100%;
    border-collapse: collapse;
    min-width: 800px;
}

.preview-table thead {
    position: sticky;
    top: 0;
    z-index: 10;
}

.preview-table th {
    background: var(--secondary-blue);
    color: white;
    font-weight: 600;
    padding: 1rem;
    text-align: left;
    border-right: 1px solid rgba(255, 255, 255, 0.1);
    white-space: nowrap;
    position: relative;
}

.preview-table th:first-child {
    background: var(--primary-blue);
    position: sticky;
    left: 0;
    z-index: 11;
}

.preview-table td {
    padding: 0.9rem 1rem;
    border-bottom: 1px solid #f1f3f5;
    border-right: 1px solid #f1f3f5;
    background: white;
}

.preview-table tr:hover td {
    background: #f8fbff;
}

.preview-table td:first-child {
    background: var(--lighter-blue);
    font-weight: 600;
    color: var(--primary-blue);
    position: sticky;
    left: 0;
    z-index: 9;
    border-right: 2px solid var(--border-blue);
}

.zero-value {
    color: #adb5bd;
    font-style: italic;
}

/* FAQ Section */
.faq-section .faq-list {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.faq-item h3 {
    color: var(--primary-blue);
    font-size: 1.1rem;
    margin-bottom: 0.5rem;
    font-weight: 600;
    display: flex;
    align-items: center;
}

.faq-item p {
    color: var(--text-medium);
    margin-left: 2rem; /* indent text under icon+number */
}

/* Info Panel */
.info-panel {
    background: white;
    border-radius: 12px;
    box-shadow: 0 4px 16px var(--shadow-light);
    overflow: hidden;
}

.info-tabs {
    display: flex;
    border-bottom: 1px solid var(--border-blue);
}

.info-tab {
    padding: 1.2rem 1.5rem;
    background: none;
    border: none;
    font-weight: 600;
    color: var(--text-medium);
    cursor: pointer;
    transition: all 0.3s;
    position: relative;
}

.info-tab.active {
    color: var(--accent-blue);
}

.info-tab.active:after {
    content: '';
    position: absolute;
    bottom: -1px;
    left: 0;
    right: 0;
    height: 3px;
    background: var(--accent-blue);
}

.info-tab:hover:not(.active) {
    background: var(--light-blue);
    color: var(--primary-blue);
}

.tab-content {
    padding: 2rem;
}

.tab-pane {
    display: none;
}

.tab-pane.active {
    display: block;
}

.info-list {
    list-style: none;
}

.info-list li {
    margin-bottom: 1rem;
    padding-left: 1.8rem;
    position: relative;
    color: var(--text-medium);
}

.info-list li:before {
    content: '✓';
    position: absolute;
    left: 0;
    color: var(--success-green);
    font-weight: bold;
}

.disclaimer-box {
    background: #fff9e6;
    border-left: 4px solid var(--warning-orange);
    padding: 1.5rem;
    border-radius: 0 8px 8px 0;
    margin-top: 1.5rem;
}

.disclaimer-box h4 {
    color: #856404;
    margin-bottom: 0.8rem;
    display: flex;
    align-items: center;
    gap: 0.8rem;
}

/* Modal */
.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.7);
    display: none;
    justify-content: center;
    align-items: center;
    z-index: 2000;
    padding: 1rem;
}

.modal {
    background: white;
    border-radius: 12px;
    width: 100%;
    max-width: 700px;
    max-height: 90vh;
    overflow-y: auto;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.2);
    animation: modalSlideIn 0.3s ease;
}

@keyframes modalSlideIn {
    from {
        opacity: 0;
        transform: translateY(-30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.modal-header {
    background: linear-gradient(135deg, var(--primary-blue) 0%, var(--secondary-blue) 100%);
    color: white;
    padding: 1.8rem;
    border-radius: 12px 12px 0 0;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.modal-header h2 {
    font-size: 1.5rem;
    display: flex;
    align-items: center;
    gap: 0.8rem;
}

.close-modal {
    background: rgba(255, 255, 255, 0.2);
    border: none;
    color: white;
    width: 40px;
    height: 40px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: background 0.3s;
}

.close-modal:hover {
    background: rgba(255, 255, 255, 0.3);
}

.modal-body {
    padding: 2rem;
}

.summary-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
    gap: 1.2rem;
    margin: 1.5rem 0;
}

.summary-item {
    background: var(--lighter-blue);
    padding: 1.5rem;
    border-radius: 8px;
    text-align: center;
}

.summary-label {
    font-size: 0.9rem;
    color: var(--text-medium);
    margin-bottom: 0.5rem;
}

.summary-value {
    font-size: 1.8rem;
    font-weight: 700;
    color: var(--primary-blue);
}

/* Footer */
.main-footer {
    background: var(--primary-blue);
    color: white;
    padding: 1.5rem 2rem;
    text-align: center;
    font-size: 0.9rem;
    margin-top: auto;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    max-width: 100%;
}

.footer-links {
    display: flex;
    gap: 1.5rem;
}

.footer-links a {
    color: rgba(255, 255, 255, 0.8);
    text-decoration: none;
    transition: color 0.3s;
}

.footer-links a:hover {
    color: white;
}

/* Loading Animation */
.loading {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 3px solid rgba(255, 255, 255, 0.3);
    border-radius: 50%;
    border-top-color: white;
    animation: spin 1s ease-in-out infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

/* Responsive */
@media (max-width: 1200px) {
    .main-content {
        padding: 1.5rem;
    }
    .header-content {
        flex-direction: column;
        align-items: flex-start;
        gap: 1rem;
    }
    .footer-content {
        flex-direction: column;
        gap: 1rem;
        text-align: center;
    }
}

@media (max-width: 768px) {
    .main-header {
        padding: 1.2rem;
    }
    .logo-text h1 {
        font-size: 1.5rem;
    }
    .upload-area {
        padding: 3rem 1rem;
    }
    .upload-text {
        font-size: 1.2rem;
    }
    .section-header {
        flex-direction: column;
        align-items: flex-start;
        gap: 1rem;
    }
    .preview-header {
        flex-direction: column;
        align-items: flex-start;
        gap: 1rem;
    }
    .sheet-selector {
        width: 100%;
    }
    .sheet-select {
        flex: 1;
        min-width: unset;
    }
    .summary-section {
        grid-template-columns: repeat(2, 1fr);
    }
    .controls-section {
        justify-content: center;
    }
}

@media (max-width: 480px) {
    .summary-section {
        grid-template-columns: 1fr;
    }
    .btn {
        width: 100%;
        justify-content: center;
    }
    .info-tabs {
        flex-wrap: wrap;
    }
    .info-tab {
        flex: 1;
        min-width: 120px;
        text-align: center;
    }
}