/* 学术前沿页面专用样式 */

.academics-hero {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 120px 0 80px 0;
    text-align: center;
}

.academics-hero h1 {
    font-size: 3em;
    margin-bottom: 20px;
    font-weight: 700;
}

.academics-hero .subtitle {
    font-size: 1.5em;
    opacity: 0.9;
    margin-bottom: 40px;
}

.stats {
    display: flex;
    justify-content: center;
    gap: 60px;
    margin-top: 50px;
}

.stat-item {
    text-align: center;
}

.stat-number {
    font-size: 3em;
    font-weight: 700;
    margin-bottom: 10px;
}

.stat-label {
    font-size: 1.1em;
    opacity: 0.8;
}

.summary-section {
    padding: 60px 0;
    background: linear-gradient(135deg, #ffffff 0%, #f5f7ff 50%, #ffffff 100%);
    min-height: 500px;
    position: relative;
}

.summary-section::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: radial-gradient(circle at 20% 50%, rgba(102, 126, 234, 0.03) 0%, transparent 50%),
                radial-gradient(circle at 80% 30%, rgba(102, 126, 234, 0.02) 0%, transparent 50%);
    pointer-events: none;
}

.summary-content {
    max-width: 900px;
    margin: 0 auto;
    background: white;
    padding: 50px;
    border-radius: 12px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.08);
}

.summary-content h1 {
    color: #333;
    font-size: 2.5em;
    margin-bottom: 30px;
    text-align: center;
}

.summary-content h2 {
    color: #667eea;
    font-size: 1.8em;
    margin-top: 40px;
    margin-bottom: 20px;
    border-bottom: 2px solid #667eea;
    padding-bottom: 10px;
}

.summary-content h3 {
    color: #555;
    font-size: 1.4em;
    margin-top: 30px;
    margin-bottom: 15px;
}

.summary-content p {
    color: #555;
    line-height: 1.8;
    margin-bottom: 15px;
    font-size: 1.05em;
}

.summary-content ul, .summary-content ol {
    margin-left: 30px;
    margin-bottom: 20px;
}

.summary-content li {
    color: #555;
    line-height: 1.8;
    margin-bottom: 10px;
}

.summary-content a {
    color: #667eea;
    text-decoration: none;
    border-bottom: 1px solid #667eea;
    transition: all 0.3s;
}

.summary-content a:hover {
    color: #5568d3;
    border-bottom-color: #5568d3;
}

.citation-link {
    display: inline-block;
    background: #e9ecef;
    color: #667eea;
    padding: 2px 8px;
    border-radius: 4px;
    font-size: 0.9em;
    cursor: pointer;
    border: none;
    transition: all 0.3s;
}

.citation-link:hover {
    background: #667eea;
    color: white;
}

.spinner {
    border: 4px solid #f3f3f3;
    border-top: 4px solid #667eea;
    border-radius: 50%;
    width: 50px;
    height: 50px;
    animation: spin 1s linear infinite;
    margin: 0 auto 20px;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

.loading {
    text-align: center;
    padding: 80px 20px;
    color: #666;
}

.loading-note {
    font-size: 0.9em;
    color: #999;
    margin-top: 10px;
}

.error-box {
    max-width: 600px;
    margin: 40px auto;
    background: #fff3cd;
    border: 1px solid #ffc107;
    border-radius: 8px;
    padding: 30px;
    text-align: center;
}

.error-box h3 {
    color: #856404;
    margin-bottom: 20px;
}

.error-box ul {
    text-align: left;
    margin: 20px 0;
}

.retry-btn, .view-all-btn {
    display: inline-block;
    margin: 10px;
    padding: 10px 30px;
    border-radius: 6px;
    text-decoration: none;
    cursor: pointer;
    font-size: 1em;
    transition: all 0.3s;
}

.retry-btn {
    background: #667eea;
    color: white;
    border: none;
}

.retry-btn:hover {
    background: #5568d3;
}

.view-all-btn {
    background: white;
    color: #667eea;
    border: 2px solid #667eea;
}

.view-all-btn:hover {
    background: #667eea;
    color: white;
}

.article-modal {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0,0,0,0.7);
    z-index: 1000;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 20px;
}

.modal-content {
    background: white;
    border-radius: 12px;
    max-width: 800px;
    max-height: 90vh;
    overflow-y: auto;
    position: relative;
    padding: 40px;
}

.modal-close {
    position: absolute;
    top: 15px;
    right: 20px;
    background: none;
    border: none;
    font-size: 40px;
    color: #999;
    cursor: pointer;
    line-height: 1;
}

.modal-close:hover {
    color: #333;
}

.article-details h2 {
    color: #333;
    margin-bottom: 20px;
}

.article-details h3 {
    color: #667eea;
    margin-top: 25px;
    margin-bottom: 15px;
}

.article-details .meta {
    color: #666;
    margin-bottom: 20px;
    padding: 15px;
    background: #f8f9fa;
    border-radius: 6px;
}

.article-details .abstract {
    color: #555;
    line-height: 1.8;
    margin: 20px 0;
}

.articles-section {
    padding: 60px 0;
    background: #f8f9fa;
}

.section-header {
    text-align: center;
    margin-bottom: 50px;
}

.section-header h2 {
    font-size: 2.5em;
    color: #333;
    margin-bottom: 15px;
}

.section-header p {
    font-size: 1.2em;
    color: #666;
}

.articles-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
    gap: 30px;
    margin-bottom: 40px;
}

.article-card {
    background: white;
    border-radius: 12px;
    padding: 25px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.08);
    transition: transform 0.3s, box-shadow 0.3s;
    cursor: pointer;
}

.article-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 5px 20px rgba(0,0,0,0.15);
}

.article-number {
    display: inline-block;
    background: #667eea;
    color: white;
    width: 35px;
    height: 35px;
    line-height: 35px;
    text-align: center;
    border-radius: 50%;
    font-weight: 700;
    margin-bottom: 15px;
}

.article-card h3 {
    color: #333;
    font-size: 1.3em;
    margin-bottom: 15px;
    line-height: 1.4;
}

.article-meta {
    color: #666;
    font-size: 0.95em;
    margin-bottom: 15px;
    display: flex;
    flex-direction: column;
    gap: 5px;
}

.meta-item {
    display: flex;
    align-items: center;
    gap: 8px;
}

.meta-label {
    font-weight: 600;
    color: #555;
}

.article-abstract {
    color: #555;
    line-height: 1.6;
    margin-bottom: 15px;
    display: -webkit-box;
    -webkit-line-clamp: 4;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.article-abstract.expanded {
    -webkit-line-clamp: unset;
    max-height: none;
}

.article-keywords {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    margin-top: 12px;
}

.keyword-tag {
    background: #e9ecef;
    color: #495057;
    padding: 4px 12px;
    border-radius: 15px;
    font-size: 0.85em;
}

.read-more-btn {
    background: #667eea;
    color: white;
    border: none;
    padding: 8px 20px;
    border-radius: 20px;
    cursor: pointer;
    font-size: 0.9em;
    transition: background 0.3s;
}

.read-more-btn:hover {
    background: #5568d3;
}

.about-section {
    padding: 60px 0;
    background: white;
}

.about-content {
    max-width: 900px;
    margin: 0 auto;
    text-align: center;
}

.about-content h2 {
    font-size: 2.5em;
    color: #333;
    margin-bottom: 20px;
}

.lead {
    font-size: 1.3em;
    color: #667eea;
    font-weight: 500;
    margin-bottom: 40px;
}

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

.feature-card {
    padding: 30px;
    background: #f8f9fa;
    border-radius: 12px;
    text-align: center;
}

.feature-icon {
    font-size: 3em;
    margin-bottom: 15px;
}

.feature-card h3 {
    color: #333;
    margin-bottom: 10px;
}

.feature-card p {
    color: #666;
}

.cta-box {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 40px;
    border-radius: 12px;
    margin-top: 50px;
    text-align: left;
}

.cta-box h3 {
    color: white;
    font-size: 1.8em;
    margin-bottom: 20px;
}

.cta-box ul {
    list-style: none;
    padding: 0;
}

.cta-box li {
    padding: 10px 0;
    font-size: 1.1em;
    border-bottom: 1px solid rgba(255,255,255,0.2);
}

.cta-box li:last-child {
    border-bottom: none;
}

.cta-section {
    padding: 60px 0;
    background: #f8f9fa;
}

.cta-section .cta-box {
    text-align: center;
    margin-top: 0;
}

.cta-section .cta-box h3 {
    text-align: center;
    margin-bottom: 15px;
}

.cta-section .cta-box p {
    text-align: center;
    margin-bottom: 25px;
    font-size: 1.1em;
}

.cta-button {
    display: inline-block;
    background: white;
    color: #667eea;
    padding: 15px 40px;
    border-radius: 30px;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s;
    border: 2px solid white;
}

.cta-button:hover {
    background: transparent;
    color: white;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .academics-hero h1 {
        font-size: 2em;
    }

    .academics-hero .subtitle {
        font-size: 1.2em;
    }

    .stats {
        flex-direction: column;
        gap: 30px;
    }

    .stat-number {
        font-size: 2.5em;
    }

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

    .section-header h2 {
        font-size: 2em;
    }

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