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

body {
    background-color: #f5f7fa;
    color: #333;
    line-height: 1.6;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

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

.main-container {
    flex: 1;
    padding: 20px 0;
    min-height: 800px;
    width: 100%;
}

/* Header */
header {
    background: linear-gradient(135deg, #2c3e50, #3498db);
    color: white;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
}

.header-top {
    padding: 15px 0;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.header-top .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.chao {
    padding-left: 70%;
}

.school-info {
    display: flex;
    align-items: center;
    gap: 20px;
}

.school-logo {
    font-size: 2.5rem;
    color: #ffd700;
}

.school-details h1 {
    font-size: 1.8rem;
    margin-bottom: 5px;
    font-weight: 700;
}

.school-details p {
    font-size: 1rem;
    opacity: 0.9;
}

.header-actions {
    display: flex;
    align-items: center;
    gap: 15px;
}

.user-section {
    display: flex;
    align-items: center;
    gap: 10px;
}

/* Navigation */
.main-nav {
    background: rgba(0, 0, 0, 0.2);
    backdrop-filter: blur(10px);
}

.main-nav .container {
    display: flex;
    justify-content: center;
}

.nav-links {
    display: flex;
    gap: 0;
}

.nav-item {
    color: white;
    text-decoration: none;
    padding: 15px 25px;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    gap: 8px;
    border-bottom: 3px solid transparent;
}

.nav-item:hover, .nav-item.active {
    background: rgba(255, 255, 255, 0.1);
    border-bottom-color: #ffd700;
}

.nav-item i {
    font-size: 1.1rem;
}

/* score-upload.css - CSS cho tính năng upload điểm */
.upload-options {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
    margin: 20px 0;
}

.upload-option {
    background: white;
    padding: 25px;
    border-radius: 10px;
    border: 2px solid #e9ecef;
    text-align: center;
    transition: all 0.3s ease;
}

.upload-option:hover {
    border-color: #3498db;
    transform: translateY(-2px);
}

.option-header {
    margin-bottom: 15px;
}

.option-header i {
    color: #3498db;
    margin-bottom: 10px;
}

.option-header h5 {
    color: #2c3e50;
    margin: 10px 0 5px 0;
}

.upload-option p {
    color: #666;
    margin-bottom: 15px;
}

.upload-area {
    border: 2px dashed #bdc3c7;
    border-radius: 8px;
    padding: 25px;
    margin-top: 15px;
    cursor: pointer;
    transition: all 0.3s ease;
}

.upload-area:hover {
    border-color: #3498db;
    background: #f8f9fa;
}

.upload-area i {
    color: #bdc3c7;
    margin-bottom: 10px;
}

.direct-input-table {
    background: white;
    border-radius: 10px;
    margin-top: 20px;
    overflow: hidden;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

.table-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 15px 20px;
    background: #f8f9fa;
    border-bottom: 1px solid #e9ecef;
}

.table-actions {
    padding: 15px 20px;
    background: #f8f9fa;
    border-top: 1px solid #e9ecef;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.score-upload-section {
    background: white;
    padding: 25px;
    border-radius: 10px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

.upload-header {
    text-align: center;
    margin-bottom: 25px;
}

.upload-header h4 {
    color: #2c3e50;
    margin-bottom: 10px;
}

.upload-header p {
    color: #666;
}

.upload-instructions {
    background: #e8f4fd;
    border-left: 4px solid #3498db;
    padding: 15px;
    margin: 15px 0;
    border-radius: 5px;
}

.upload-instructions h5 {
    color: #2c3e50;
    margin-bottom: 8px;
}

.upload-instructions ul {
    margin: 0;
    padding-left: 20px;
}

.upload-instructions li {
    margin-bottom: 5px;
    color: #555;
}

/* Buttons */
.vetrangchu {
    margin-right: 15px;
}

.vetrangchu .btn {
    padding: 10px 20px;
    border: 2px solid white;
    background: transparent;
    color: white;
    text-decoration: none;
    border-radius: 5px;
    font-weight: 600;
    transition: all 0.3s ease;
    display: inline-flex;
    align-items: center;
    gap: 8px;
}

.vetrangchu .btn:hover {
    background: white;
    color: #2c3e50;
}

button#clear-filters {
    background: rgb(110, 110, 255);
    margin-top: 28px;
}

/* CSS cho card lớp học */
.class-card {
    background: white;
    padding: 20px;
    border-radius: 10px;
    border-left: 4px solid #3498db;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.05);
    transition: transform 0.3s ease;
}

.class-card:hover {
    transform: translateY(-5px);
}

.class-card h5 {
    color: #2c3e50;
    margin-bottom: 15px;
    display: flex;
    align-items: center;
    gap: 8px;
}

.class-stats {
    display: flex;
    gap: 20px;
    margin-bottom: 15px;
}

.stat {
    text-align: center;
}

.stat-value {
    display: block;
    font-size: 1.5rem;
    font-weight: bold;
    color: #3498db;
}

.stat-label {
    font-size: 0.8rem;
    color: #666;
}

.class-subjects {
    font-size: 0.9rem;
    color: #666;
    padding-top: 10px;
    border-top: 1px solid #f0f0f0;
}

.btn {
    padding: 10px 20px;
    border: none;
    border-radius: 5px;
    font-size: 0.95rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    display: inline-flex;
    align-items: center;
}

.btn i {
    margin-right: 8px;
}

.btn-primary {
    margin-top: 20px;
    background: #3498db;
    color: white;
}

.btn-primary:hover {
    background: #2980b9;
}

.btn-outline {
    background: transparent;
    color: white;
    border: 2px solid white;
    text-decoration: none;
    white-space: nowrap;
    min-width: 120px;
}

.btn-outline:hover {
    background: white;
    color: #2c3e50;
}

.btn-secondary {
    background: #6c757d;
    color: white;
    margin-top: 20px;
}

.btn-secondary:hover {
    background: #5a6268;
}

button#export-students-btn {
    margin-top: 20px;
}

button#download-template-btn {
    margin-top: 20px;
    background-color: #2980b9;
}

#generate-report.btn.btn-primary {
    margin: 0px;
}

#export-report.btn.btn-info {
    background-color: #55afec;
    color: white;
}

/* Footer */
footer {
    background: linear-gradient(135deg, #2c3e50, #34495e);
    color: white;
    margin-top: auto;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 40px;
    padding: 50px 0 30px;
}

.footer-section h3 {
    color: #ffd700;
    margin-bottom: 20px;
    font-size: 1.2rem;
    border-left: 4px solid #3498db;
    padding-left: 10px;
}

.footer-section ul {
    list-style: none;
}

.footer-section ul li {
    margin-bottom: 10px;
}

.footer-section ul li a {
    color: #bdc3c7;
    text-decoration: none;
    transition: color 0.3s ease;
    display: flex;
    align-items: center;
    gap: 8px;
}

.footer-section ul li a:hover {
    color: #3498db;
}

.footer-section ul li a i {
    font-size: 0.8rem;
    color: #3498db;
}

#user-info {
    padding: 5px;
}

.contact-info p {
    margin-bottom: 12px;
    display: flex;
    align-items: center;
    gap: 10px;
    color: #bdc3c7;
}

.contact-info i {
    color: #3498db;
    width: 20px;
}

.social-links {
    display: flex;
    gap: 15px;
    margin-bottom: 25px;
}

.social-link {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 50%;
    color: white;
    text-decoration: none;
    transition: all 0.3s ease;
}

.social-link:hover {
    background: #3498db;
    transform: translateY(-2px);
}

.certification p {
    margin-bottom: 8px;
    font-size: 0.9rem;
    color: #bdc3c7;
    display: flex;
    align-items: center;
    gap: 8px;
}

.certification i {
    color: #27ae60;
}

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    padding: 20px 0;
}

.footer-bottom-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 15px;
}

.footer-bottom p {
    color: #bdc3c7;
    font-size: 0.9rem;
}

.footer-links {
    display: flex;
    gap: 20px;
}

.footer-links a {
    color: #bdc3c7;
    text-decoration: none;
    font-size: 0.9rem;
    transition: color 0.3s ease;
}

.footer-links a:hover {
    color: #3498db;
}

/* Hero Section */
.hero-section {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 60px 50px;
    border-radius: 15px;
    margin-bottom: 30px;
    text-align: center;
}

.hero-content h2 {
    font-size: 2.5rem;
    margin-bottom: 15px;
}

.hero-content p {
    font-size: 1.2rem;
    margin-bottom: 30px;
    opacity: 0.9;
}

.hero-features {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
    margin-top: 40px;
}

.feature {
    background: rgba(255, 255, 255, 0.1);
    padding: 30px;
    border-radius: 10px;
    backdrop-filter: blur(10px);
    transition: transform 0.3s ease;
}

.feature:hover {
    transform: translateY(-5px);
}

.feature i {
    font-size: 2.5rem;
    margin-bottom: 15px;
    color: #ffd700;
}

.feature h3 {
    font-size: 1.3rem;
    margin-bottom: 10px;
}

/* Quick News */
.quick-news {
    background: white;
    padding: 30px;
    border-radius: 15px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.05);
    margin-bottom: 30px;
}

.quick-news h3 {
    color: #2c3e50;
    margin-bottom: 20px;
    display: flex;
    align-items: center;
    gap: 10px;
}

.news-list {
    display: grid;
    gap: 15px;
}

.news-item {
    padding: 15px;
    border-left: 4px solid #3498db;
    background: #f8f9fa;
    border-radius: 5px;
}

.news-item h4 {
    color: #2c3e50;
    margin-bottom: 5px;
}

.news-item p {
    color: #666;
    font-size: 0.9rem;
}

.news-item .news-date {
    color: #888;
    font-size: 0.8rem;
    margin-top: 5px;
}

/* Page Header - FIXED SIZE */
.page-header {
    text-align: center;
    margin-bottom: 30px;
    padding: 40px 30px;
    background: white;
    border-radius: 15px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.05);
    min-height: 180px;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    box-sizing: border-box;
}

.page-header h2 {
    color: #2c3e50;
    margin-bottom: 15px;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    font-size: 2rem;
    text-align: center;
    line-height: 1.3;
}

.page-header p {
    color: #666;
    margin: 0;
    max-width: 600px;
    line-height: 1.5;
    font-size: 1.1rem;
}

/* Pages */
.page {
    display: none;
    min-height: 800px;
}

.page.active {
    display: block;
    min-height: 800px;
}

/* News Page */
.news-categories {
    display: flex;
    gap: 10px;
    margin-bottom: 30px;
    flex-wrap: wrap;
    justify-content: center;
}

.category-btn {
    padding: 10px 20px;
    border: 2px solid #3498db;
    background: white;
    color: #3498db;
    border-radius: 25px;
    cursor: pointer;
    transition: all 0.3s ease;
    font-weight: 600;
}

.category-btn.active, .category-btn:hover {
    background: #3498db;
    color: white;
}

/* News Grid - FIXED SIZE CARDS */
.news-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr); /* CỐ ĐỊNH 3 CỘT */
    gap: 30px;
    min-height: 600px;
    grid-auto-rows: 520px;
}

.news-card {
    width: 100%;
    height: 520px;
}

.news-card.hidden {
    display: none;
}

.news-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.1);
}

.news-image {
    height: 200px;
    background: linear-gradient(135deg, #667eea, #764ba2);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 3rem;
    flex-shrink: 0;
}

.news-image.special-1 {
    background: linear-gradient(135deg, #e74c3c, #c0392b);
}

.news-image.special-2 {
    background: linear-gradient(135deg, #27ae60, #219a52);
}

.news-content {
    padding: 25px;
    flex: 1;
    display: flex;
    flex-direction: column;
}

.news-category {
    display: inline-block;
    padding: 5px 15px;
    background: #3498db;
    color: white;
    border-radius: 15px;
    font-size: 0.8rem;
    margin-bottom: 15px;
    font-weight: 600;
}

.news-card h3 {
    color: #2c3e50;
    margin-bottom: 12px;
    font-size: 1.3rem;
    line-height: 1.4;
    flex-shrink: 0;
}

.news-card p {
    color: #666;
    margin-bottom: 15px;
    line-height: 1.6;
    flex: 1;
}

.news-details {
    margin: 15px 0;
    padding: 15px;
    background: #f8f9fa;
    border-radius: 8px;
    border-left: 4px solid #3498db;
    flex-shrink: 0;
}

.news-details h4 {
    color: #2c3e50;
    margin-bottom: 10px;
    font-size: 1rem;
    font-weight: 600;
}

.news-details ul {
    list-style: none;
    padding: 0;
    margin: 10px 0;
}

.news-details li {
    padding: 5px 0;
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 0.9rem;
}

.event-schedule {
    margin: 15px 0;
    flex-shrink: 0;
}

.event-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 8px 0;
    border-bottom: 1px solid #e9ecef;
}

.event-item:last-child {
    border-bottom: none;
}

.event-date {
    background: #3498db;
    color: white;
    padding: 4px 8px;
    border-radius: 4px;
    font-size: 0.85rem;
    font-weight: 600;
}

.event-desc {
    color: #2c3e50;
    font-size: 0.9rem;
    flex: 1;
    margin-left: 15px;
}

.event-note {
    background: #fff3cd;
    border: 1px solid #ffeaa7;
    padding: 10px;
    border-radius: 5px;
    margin-top: 10px;
    font-size: 0.9rem;
    color: #856404;
    flex-shrink: 0;
}

.news-meta {
    display: flex;
    justify-content: space-between;
    color: #888;
    font-size: 0.8rem;
    margin-top: auto;
    flex-shrink: 0;
    padding-top: 15px;
    border-top: 1px solid #f0f0f0;
}

/* Forum Page */
.forum-container {
    background: white;
    padding: 30px;
    border-radius: 15px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.05);
}

.forum-actions {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 25px;
    flex-wrap: wrap;
    gap: 15px;
}

.search-box {
    position: relative;
    width: 300px;
}

.search-box input {
    width: 100%;
    padding: 10px 15px 10px 40px;
    border: 1px solid #ddd;
    border-radius: 5px;
    font-size: 0.95rem;
}

.search-box i {
    position: absolute;
    left: 15px;
    top: 50%;
    transform: translateY(-50%);
    color: #777;
}

.forum-topics {
    display: grid;
    gap: 15px;
}

.topic-card {
    background: #f8f9fa;
    padding: 20px;
    border-radius: 10px;
    border-left: 4px solid #3498db;
    transition: background-color 0.3s ease;
}

.topic-card:hover {
    background: #e9ecef;
}

.topic-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 10px;
}

.topic-title {
    font-size: 1.1rem;
    color: #2c3e50;
    font-weight: 600;
    margin-bottom: 5px;
}

.topic-category {
    display: inline-block;
    padding: 3px 10px;
    background: #3498db;
    color: white;
    border-radius: 12px;
    font-size: 0.7rem;
    margin-left: 10px;
}

.topic-author {
    color: #666;
    font-size: 0.9rem;
}

.topic-stats {
    display: flex;
    gap: 15px;
    color: #888;
    font-size: 0.8rem;
}

.topic-preview {
    color: #666;
    margin-top: 10px;
    line-height: 1.4;
}

/* Score Search */
.score-search-container {
    background: white;
    padding: 30px;
    border-radius: 15px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.05);
}

.search-form {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 20px;
    margin-bottom: 30px;
    padding: 20px;
    background: #f8f9fa;
    border-radius: 10px;
}

.form-group {
    display: flex;
    flex-direction: column;
}

.form-group label {
    margin-bottom: 5px;
    font-weight: 600;
    color: #495057;
}

.form-group input, .form-group select {
    padding: 10px 15px;
    border: 1px solid #ddd;
    border-radius: 5px;
    font-size: 0.95rem;
}

.score-results {
    min-height: 200px;
}

.no-results {
    text-align: center;
    padding: 40px 20px;
    color: #666;
}

.no-results i {
    margin-bottom: 20px;
    color: #bdc3c7;
}

.no-results h3 {
    color: #2c3e50;
    margin-bottom: 10px;
}

/* Teacher Redirect */
.teacher-redirect {
    background: white;
    padding: 50px 30px;
    border-radius: 15px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.05);
    text-align: center;
}

.redirect-content i {
    margin-bottom: 20px;
    color: #3498db;
}

.redirect-content h3 {
    color: #2c3e50;
    margin-bottom: 15px;
}

/* Modal */
.modal {
    display: none;
    position: fixed;
    z-index: 1000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.5);
    animation: fadeIn 0.3s;
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

.modal-content {
    background-color: white;
    margin: 5% auto;
    border-radius: 10px;
    width: 90%;
    max-width: 500px;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
    animation: slideIn 0.3s;
}

@keyframes slideIn {
    from { transform: translateY(-50px); opacity: 0; }
    to { transform: translateY(0); opacity: 1; }
}

.modal-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px;
    border-bottom: 1px solid #eee;
}

.modal-header h3 {
    margin: 0;
    color: #2c3e50;
}

.close {
    font-size: 1.5rem;
    font-weight: bold;
    cursor: pointer;
    color: #777;
}

.close:hover {
    color: #333;
}

.modal-body {
    padding: 20px;
}

.form-group textarea {
    resize: vertical;
    min-height: 100px;
    padding: 10px 15px;
    border: 1px solid #ddd;
    border-radius: 5px;
    font-size: 0.95rem;
    font-family: inherit;
}

.form-actions {
    display: flex;
    justify-content: flex-end;
    gap: 10px;
    margin-top: 20px;
}

.classes-container {
    padding: 30px;
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 30px;
}

.classes-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
    gap: 20px;
}

.teaching-info {
    background: white;
    padding: 25px;
    border-radius: 10px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.05);
    height: fit-content;
}

.info-card {
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.info-item {
    display: flex;
    align-items: center;
    gap: 15px;
    padding: 15px 0;
    border-bottom: 1px solid #f0f4f8;
}

.info-item:last-child {
    border-bottom: none;
}

.info-item i {
    font-size: 1.5rem;
    color: #3498db;
    width: 30px;
}

.info-content h5 {
    margin: 0 0 5px 0;
    color: #2c3e50;
    font-size: 0.9rem;
}

.info-content p {
    margin: 0;
    color: #666;
    font-size: 1rem;
    font-weight: 600;
}

/* Utility Classes */
.hidden {
    display: none !important;
}

.teacher-only {
    display: none;
}

.teacher-only.show {
    display: flex !important;
}

/* ===== FIX KÍCH THƯỚC MAIN CONTAINER ===== */
.main-container {
    flex: 1;
    padding: 20px 0;
    min-height: 800px;
    width: 100%;
}

/* FIX KÍCH THƯỚC TẤT CẢ CÁC TRANG */
.page {
    display: none;
    min-height: 800px;
}

.page.active {
    display: block;
    min-height: 800px;
}

/* FIX GRID CONTAINER - CỐ ĐỊNH 3 CỘT */
.news-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
    min-height: 600px;
    grid-auto-rows: 520px;
    align-items: start;
}

.news-card {
    width: 100%;
    height: 520px;
    display: flex;
    flex-direction: column;
}

.news-card.hidden {
    display: none !important;
}

/* Message khi không có tin tức */
.no-news-message {
    grid-column: 1 / -1;
    text-align: center;
    padding: 60px 20px;
    color: #666;
}

.no-news-message i {
    margin-bottom: 20px;
    color: #bdc3c7;
}

.no-news-message h3 {
    color: #2c3e50;
    margin-bottom: 10px;
}

/* ===== TEACHER DASHBOARD STYLES ===== */

/* Main Container */
.teacher-dashboard {
    background: white;
    border-radius: 15px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.05);
    overflow: hidden;
}

.teacher-welcome {
    padding: 30px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
}

.teacher-welcome h2 {
    margin-bottom: 20px;
    font-size: 2rem;
}

.teacher-stats {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 20px;
}

.stat-card {
    background: rgba(255, 255, 255, 0.1);
    padding: 25px;
    border-radius: 10px;
    backdrop-filter: blur(10px);
    display: flex;
    align-items: center;
    gap: 15px;
    transition: transform 0.3s ease;
}

.stat-card:hover {
    transform: translateY(-5px);
}

.stat-icon {
    font-size: 2.5rem;
    opacity: 0.9;
}

.stat-info h3 {
    font-size: 0.9rem;
    margin-bottom: 5px;
    opacity: 0.9;
}

.stat-info p {
    font-size: 2rem;
    font-weight: bold;
    margin: 0;
}

/* Tab Navigation */
.main-nav .nav-item.active {
    background: white;
    border-bottom-color: #3498db;
    color: #3498db;
}

/* Tab Content */
.tab-content {
    display: none;
    padding: 0;
}

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

.tab-header {
    padding: 30px;
    background: white;
    border-bottom: 1px solid #e9ecef;
}

.tab-header h3 {
    color: #2c3e50;
    margin-bottom: 10px;
    display: flex;
    align-items: center;
    gap: 10px;
}

.tab-header p {
    color: #666;
    margin: 0;
}

/* Action Bar */
.action-bar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px 30px;
    background: white;
    border-bottom: 1px solid #e9ecef;
    flex-wrap: wrap;
    gap: 15px;
}

.action-group {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
}

.search-box {
    position: relative;
    width: 300px;
}

.search-box input {
    width: 100%;
    padding: 10px 15px 10px 40px;
    border: 1px solid #ddd;
    border-radius: 5px;
    font-size: 0.95rem;
}

.search-box i {
    position: absolute;
    left: 15px;
    top: 50%;
    transform: translateY(-50%);
    color: #777;
}

/* Filter Bar */
.filter-bar {
    display: flex;
    gap: 15px;
    padding: 15px 30px;
    background: #f8f9fa;
    border-bottom: 1px solid #e9ecef;
    align-items: center;
    flex-wrap: wrap;
}

.filter-bar .form-group {
    margin: 0;
}

.filter-bar label {
    margin-bottom: 5px;
    font-weight: 600;
    color: #495057;
    font-size: 0.9rem;
}

.filter-bar select {
    padding: 8px 12px;
    border: 1px solid #ddd;
    border-radius: 5px;
    font-size: 0.9rem;
}

/* Table Container */
.table-container {
    padding: 0 30px 30px;
}

table {
    width: 100%;
    border-collapse: collapse;
    background: white;
    border-radius: 10px;
    overflow: hidden;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.05);
}

table th {
    background: #34495e;
    color: white;
    font-weight: 600;
    padding: 15px 12px;
    text-align: left;
    border-bottom: 1px solid #2c3e50;
}

table td {
    padding: 12px 15px;
    border-bottom: 1px solid #f0f4f8;
    vertical-align: middle;
}

table tr:hover {
    background: #f8f9fa;
}

/* Subjects Grid */
.subjects-container {
    padding: 30px;
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 30px;
}

.subjects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 15px;
}

.subject-card {
    background: white;
    padding: 20px;
    border-radius: 10px;
    border-left: 4px solid #3498db;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.05);
}

.subject-card h5 {
    color: #2c3e50;
    margin-bottom: 10px;
    display: flex;
    align-items: center;
    gap: 8px;
}

.subject-card p {
    color: #666;
    margin: 0;
    font-size: 0.9rem;
}

/* Score Structure */
.structure-card {
    background: white;
    padding: 25px;
    border-radius: 10px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.05);
}

.structure-item {
    display: flex;
    align-items: center;
    gap: 15px;
    padding: 15px 0;
    border-bottom: 1px solid #f0f4f8;
}

.structure-item:last-child {
    border-bottom: none;
}

.structure-item i {
    font-size: 1.5rem;
    color: #3498db;
    width: 30px;
}

.structure-info h5 {
    margin: 0 0 5px 0;
    color: #2c3e50;
}

.structure-info p {
    margin: 0;
    color: #666;
    font-size: 0.9rem;
}

/* Score Controls */
.score-controls {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 15px;
    padding: 20px 30px;
    background: #f8f9fa;
    border-bottom: 1px solid #e9ecef;
}

.score-controls .form-group {
    margin: 0;
}

/* Score Table */
.score-table-container {
    padding: 0 30px 30px;
}

.score-input-table {
    width: 100%;
    border-collapse: collapse;
    background: white;
    border-radius: 10px;
    overflow: hidden;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.05);
}

.score-input-table th {
    background: #2980b9;
    color: white;
    padding: 12px 10px;
    text-align: center;
    font-weight: 600;
}

.score-input-table td {
    padding: 10px 8px;
    text-align: center;
    border-bottom: 1px solid #f0f4f8;
}

.score-input {
    width: 70px;
    padding: 8px;
    border: 1px solid #ddd;
    border-radius: 4px;
    text-align: center;
    font-size: 0.9rem;
    transition: all 0.3s ease;
}

.score-input:focus {
    border-color: #3498db;
    box-shadow: 0 0 0 2px rgba(52, 152, 219, 0.2);
    outline: none;
}

.score-input.invalid {
    border-color: #e74c3c;
    background-color: #fdf2f2;
}

/* Report Controls */
.report-controls {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 15px;
    padding: 20px 30px;
    background: #f8f9fa;
    border-bottom: 1px solid #e9ecef;
}

.report-content {
    padding: 30px;
}

/* Form Styles */
.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 15px;
}

.form-group {
    display: flex;
    flex-direction: column;
    margin-bottom: 15px;
}

.form-group label {
    margin-bottom: 5px;
    font-weight: 600;
    color: #495057;
}

.form-group input,
.form-group select {
    padding: 10px 15px;
    border: 1px solid #ddd;
    border-radius: 5px;
    font-size: 0.95rem;
    transition: border-color 0.3s ease;
}

.form-group input:focus,
.form-group select:focus {
    border-color: #3498db;
    outline: none;
    box-shadow: 0 0 0 2px rgba(52, 152, 219, 0.2);
}

.form-actions {
    display: flex;
    justify-content: flex-end;
    gap: 10px;
    margin-top: 20px;
    padding-top: 20px;
    border-top: 1px solid #e9ecef;
}

/* Utility Classes */
.class-badge {
    background: #3498db;
    color: white;
    padding: 4px 8px;
    border-radius: 12px;
    font-size: 0.8rem;
    font-weight: 600;
}

.grade-A { color: #27ae60; font-weight: 600; }
.grade-B { color: #3498db; font-weight: 600; }
.grade-C { color: #f39c12; font-weight: 600; }
.grade-D { color: #e67e22; font-weight: 600; }
.grade-F { color: #e74c3c; font-weight: 600; }

.btn-sm {
    padding: 6px 12px;
    font-size: 0.85rem;
}

/* No Data Message */
.no-data-message,
.report-placeholder {
    text-align: center;
    padding: 60px 20px;
    color: #666;
}

.no-data-message i,
.report-placeholder i {
    margin-bottom: 20px;
    color: #bdc3c7;
}

.no-data-message h3,
.report-placeholder h3 {
    color: #2c3e50;
    margin-bottom: 10px;
}

/* Auto-save Indicator */
.auto-save-indicator {
    position: fixed;
    top: 20px;
    right: 20px;
    background: #27ae60;
    color: white;
    padding: 10px 15px;
    border-radius: 5px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.2);
    display: none;
    z-index: 1000;
}

/* ===== RESPONSIVE FIXES ===== */

/* Responsive Header Fix */
@media (max-width: 768px) {
    .header-top .container {
        flex-direction: column;
        gap: 15px;
        text-align: center;
        padding: 10px 0;
    }
    
    .school-info {
        flex-direction: column;
        text-align: center;
        gap: 10px;
    }
    
    .school-details h1 {
        font-size: 1.4rem;
        line-height: 1.3;
    }
    
    .school-details p {
        font-size: 0.9rem;
    }
    
    .header-actions {
        flex-direction: column;
        gap: 10px;
        width: 100%;
    }
    
    .user-section {
        display: flex;
        flex-direction: column;
        gap: 10px;
        width: 100%;
    }
    
    .user-section .btn {
        margin-right: 4%;
        padding: 10px 33px;
        justify-content: center;
    }
    
    #user-info {
        order: -1;
        margin-bottom: 10px;
        font-size: 0.9rem;
        text-align: center;
        padding: 8px;
        background: rgba(255, 255, 255, 0.1);
        border-radius: 5px;
        width: 100%;
    }
    
    .chao {
        padding-left: 0;
        text-align: center;
        width: 100%;
        margin-top: 10px;
    }
}

/* Responsive Navigation Fix */
@media (max-width: 768px) {
    .nav-links {
        flex-direction: column;
        width: 100%;
        gap: 0;
    }
    
    .nav-item {
        justify-content: flex-start;
        padding: 12px 20px;
        border-bottom: 1px solid rgba(255, 255, 255, 0.1);
        border-left: 3px solid transparent;
    }
    
    .nav-item.active {
        border-left-color: #ffd700;
        border-bottom-color: rgba(255, 255, 255, 0.1);
    }
    
    .nav-item:hover {
        border-left-color: #ffd700;
    }
    
    .teacher-only.show {
        display: flex !important;
    }
}

/* Responsive Hero Section */
@media (max-width: 768px) {
    .hero-section {
        padding: 30px 20px;
        margin: 15px 0;
    }
    
    .hero-content h2 {
        font-size: 1.8rem;
        margin-bottom: 10px;
    }
    
    .hero-content p {
        font-size: 1rem;
        margin-bottom: 20px;
    }
    
    .hero-features {
        grid-template-columns: 1fr;
        gap: 20px;
        margin-top: 30px;
    }
    
    .feature {
        padding: 20px;
    }
    
    .feature i {
        font-size: 2rem;
    }
    
    .feature h3 {
        font-size: 1.1rem;
    }
}

/* Responsive Quick News */
@media (max-width: 768px) {
    .quick-news {
        padding: 20px;
        margin: 15px 0;
    }
    
    .quick-news h3 {
        font-size: 1.2rem;
        margin-bottom: 15px;
    }
    
    .news-list {
        gap: 10px;
    }
    
    .news-item {
        padding: 12px;
    }
    
    .news-item h4 {
        font-size: 1rem;
    }
    
    .news-item p {
        font-size: 0.85rem;
    }
}

/* Responsive News Grid */
@media (max-width: 1200px) {
    .news-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    .news-grid {
        grid-template-columns: 1fr;
    }
    
    .main-container {
        min-height: 700px;
    }
    
    .page {
        min-height: 700px;
    }
    
    .page.active {
        min-height: 700px;
    }
    
    .news-card {
        height: auto;
        min-height: 500px;
    }
}

/* Responsive General */
@media (max-width: 768px) {
    .container {
        padding: 0 15px;
    }
    
    .main-container {
        padding: 10px 0;
        min-height: auto;
    }
    
    .page-header {
        padding: 30px 20px;
        min-height: 160px;
    }
    
    .page-header h2 {
        font-size: 1.5rem;
    }
    
    .btn-outline {
        margin: 0% 4%;
        min-width: 100px;
        padding: 8px 15px;
        font-size: 0.9rem;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 10px;
    }
    
    .news-grid {
        grid-template-columns: 1fr;
    }
    
    .news-card {
        height: auto;
        min-height: 500px;
    }
    
    .hero-section {
        padding: 20px 15px;
    }
    
    .hero-content h2 {
        font-size: 1.5rem;
    }
    
    .hero-content p {
        font-size: 0.9rem;
    }
    
    .header-actions {
        gap: 8px;
    }
}

/* Responsive Teacher Dashboard */
@media (max-width: 768px) {
    .teacher-stats {
        grid-template-columns: 1fr;
    }
    
    .action-bar {
        flex-direction: column;
        align-items: stretch;
    }
    
    .action-group {
        justify-content: center;
    }
    
    .search-box {
        width: 100%;
    }
    
    .filter-bar {
        flex-direction: column;
        align-items: stretch;
    }
    
    .subjects-container {
        grid-template-columns: 1fr;
    }
    
    .score-controls,
    .report-controls {
        grid-template-columns: 1fr;
    }
    
    .form-row {
        grid-template-columns: 1fr;
    }
    
    .table-container {
        overflow-x: auto;
    }
    
    table {
        min-width: 800px;
    }
}

/* Responsive Forum */
@media (max-width: 768px) {
    .forum-actions {
        flex-direction: column;
        align-items: stretch;
    }
    
    .search-box {
        width: 100%;
    }
}

/* Responsive Footer */
@media (max-width: 768px) {
    .footer-content {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .footer-bottom-content {
        flex-direction: column;
        text-align: center;
    }
    
    .footer-links {
        justify-content: center;
    }
    
    .event-item {
        flex-direction: column;
        align-items: flex-start;
        gap: 5px;
    }
    
    .event-desc {
        margin-left: 0;
    }
}

/* Responsive Upload Options */
@media (max-width: 768px) {
    .upload-options {
        grid-template-columns: 1fr;
    }
    
    .upload-option {
        padding: 20px;
    }
    
    .table-header {
        flex-direction: column;
        gap: 10px;
        text-align: center;
    }
}

/* Responsive Score Search */
@media (max-width: 768px) {
    .search-form {
        grid-template-columns: 1fr;
    }
}

/* Upload Notification Styles */
.upload-notification {
    position: fixed;
    top: 20px;
    right: 20px;
    background: white;
    border-radius: 8px;
    box-shadow: 0 4px 12px rgba(0,0,0,0.15);
    z-index: 1000;
    max-width: 500px;
    border-left: 4px solid #3498db;
    animation: slideInRight 0.3s ease;
}

.upload-notification.success {
    border-left-color: #27ae60;
}

.upload-notification.error {
    border-left-color: #e74c3c;
}

.upload-notification.warning {
    border-left-color: #f39c12;
}

.notification-content {
    padding: 15px;
    display: flex;
    align-items: flex-start;
    gap: 10px;
}

.notification-content i {
    margin-top: 2px;
    flex-shrink: 0;
    font-size: 18px;
}

.notification-content.success i {
    color: #27ae60;
}

.notification-content.error i {
    color: #e74c3c;
}

.notification-content.warning i {
    color: #f39c12;
}

.notification-content pre {
    margin: 0;
    white-space: pre-wrap;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    font-size: 14px;
    line-height: 1.4;
    color: #2c3e50;
}

@keyframes slideInRight {
    from {
        transform: translateX(100%);
        opacity: 0;
    }
    to {
        transform: translateX(0);
        opacity: 1;
    }
}

/* Loading indicator */
.upload-loading {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    color: #3498db;
}

.upload-loading::after {
    content: '';
    width: 12px;
    height: 12px;
    border: 2px solid #3498db;
    border-right-color: transparent;
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

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