/* Timeline styles */
.timeline {
    position: relative;
    padding: 2rem 0;
    max-width: 1200px;
    margin: 0 auto;
}

.timeline::before {
    content: '';
    position: absolute;
    left: 50%;
    transform: translateX(-50%);
    width: 3px;
    height: 100%;
    background: linear-gradient(to bottom, 
        rgba(52, 152, 219, 0.1),
        rgba(52, 152, 219, 0.4),
        rgba(52, 152, 219, 0.1)
    );
}

/* Timeline Group Headers */
.timeline-group-header {
    text-align: center;
    margin: 3rem 0 2rem;
    position: relative;
    z-index: 2;
}

.timeline-group-header:first-child {
    margin-top: 1rem;
}

.timeline-group-header h3 {
    display: inline-block;
    background: linear-gradient(135deg, #2c3e50, #3498db);
    color: #fff;
    padding: 0.6rem 1.8rem;
    border-radius: 25px;
    font-size: 1.1rem;
    font-weight: 500;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

/* Timeline items */
.timeline-item {
    margin-bottom: 3rem;
    position: relative;
    width: 100%;
    opacity: 1;
    transform: none;
    transition: all 0.4s ease-out;
}

.timeline-item.animate {
    opacity: 0;
    transform: translateY(20px);
}

.timeline-item.animate.visible {
    opacity: 1;
    transform: translateY(0);
}

/* Timeline dots */
.timeline-dot {
    position: absolute;
    left: 50%;
    transform: translateX(-50%);
    width: 16px;
    height: 16px;
    border-radius: 50%;
    background: #3498db;
    border: 3px solid #fff;
    box-shadow: 0 0 0 3px rgba(52, 152, 219, 0.3);
    transition: all 0.3s ease;
    z-index: 2;
}

.timeline-item.current .timeline-dot {
    background: #2ecc71;
    box-shadow: 0 0 0 3px rgba(46, 204, 113, 0.3);
}

.timeline-date {
    position: absolute;
    top: -2px;
    left: 0;
    width: calc(50% - 50px);
    text-align: right;
    padding: 6px 30px;
    color: #2c3e50;
    font-weight: 500;
    font-size: 0.95rem;
}

/* Timeline content */
.timeline-content {
    margin-left: calc(50% + 50px);
    background: #fff;
    padding: 1.8rem;
    border-radius: 12px;
    box-shadow: 0 4px 20px rgba(0,0,0,0.08);
    transition: all 0.3s ease;
    border: 1px solid rgba(52, 152, 219, 0.1);
    position: relative;
}

.timeline-content::before {
    content: '';
    position: absolute;
    left: -15px;
    top: 20px;
    border-style: solid;
    border-width: 10px 15px 10px 0;
    border-color: transparent #fff transparent transparent;
    filter: drop-shadow(-3px 0px 2px rgba(0,0,0,0.05));
}

.timeline-content h3 {
    margin: 0 0 0.8rem;
    color: #2c3e50;
    font-size: 1.3rem;
    font-weight: 600;
    line-height: 1.4;
}

.timeline-content .institution {
    color: #3498db;
    font-weight: 500;
    margin-bottom: 1rem;
    font-size: 1.1rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.timeline-details {
    margin-top: 1.2rem;
    padding-top: 1.2rem;
    border-top: 1px solid rgba(52, 152, 219, 0.1);
}

.timeline-details ul {
    margin: 0;
    padding-left: 1.2rem;
    list-style-type: none;
}

.timeline-details li {
    margin-bottom: 0.8rem;
    position: relative;
    padding-left: 1.5rem;
    line-height: 1.6;
}

.timeline-details li::before {
    content: '•';
    color: #3498db;
    font-weight: bold;
    position: absolute;
    left: 0;
    top: 0;
}

.timeline-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-top: 1rem;
}

.timeline-tag {
    background: rgba(52, 152, 219, 0.1);
    color: #2c3e50;
    padding: 0.3rem 0.8rem;
    border-radius: 15px;
    font-size: 0.9rem;
    font-weight: 500;
}

/* Hover Effects */
@media (hover: hover) {
    .timeline-content:hover {
        transform: translateY(-5px);
        box-shadow: 0 8px 25px rgba(0,0,0,0.1);
    }

    .timeline-dot:hover {
        transform: translateX(-50%) scale(1.2);
        background: #2980b9;
    }

    .timeline-item.current .timeline-dot:hover {
        background: #27ae60;
    }
}

/* Mobile Styles */
@media (max-width: 768px) {
    .timeline::before {
        left: 30px;
    }

    .timeline-group-header {
        text-align: left;
        margin-left: 60px;
    }

    .timeline-group-header h3 {
        font-size: 1rem;
        padding: 0.4rem 1.2rem;
    }

    .timeline-item {
        margin-bottom: 2.5rem;
    }

    .timeline-dot {
        left: 30px;
        transform: none;
        width: 14px;
        height: 14px;
        border-width: 2px;
    }

    .timeline-date {
        position: relative;
        width: auto;
        text-align: left;
        padding: 4px 12px;
        margin-left: 60px;
        margin-bottom: 0.5rem;
        background: rgba(52, 152, 219, 0.1);
        border-radius: 15px;
        font-size: 0.9rem;
        display: inline-block;
    }

    .timeline-content {
        margin-left: 60px;
        padding: 1.5rem;
    }

    .timeline-content::before {
        left: -12px;
        border-width: 8px 12px 8px 0;
    }

    .timeline-content h3 {
        font-size: 1.2rem;
    }

    .timeline-content .institution {
        font-size: 1rem;
    }

    .timeline-details {
        margin-top: 1rem;
        padding-top: 1rem;
    }

    .timeline-details li {
        font-size: 0.95rem;
    }

    .timeline-tags {
        margin-top: 0.8rem;
    }

    .timeline-tag {
        font-size: 0.85rem;
        padding: 0.25rem 0.6rem;
    }
}

/* Small Mobile Styles */
@media (max-width: 480px) {
    .timeline::before {
        left: 20px;
    }

    .timeline-group-header {
        margin-left: 45px;
    }

    .timeline-group-header h3 {
        font-size: 0.9rem;
        padding: 0.3rem 1rem;
    }

    .timeline-dot {
        left: 20px;
        width: 12px;
        height: 12px;
    }

    .timeline-date {
        margin-left: 45px;
        font-size: 0.85rem;
        padding: 3px 10px;
    }

    .timeline-content {
        margin-left: 45px;
        padding: 1.2rem;
    }

    .timeline-content h3 {
        font-size: 1.1rem;
    }

    .timeline-content .institution {
        font-size: 0.95rem;
    }

    .timeline-details li {
        font-size: 0.9rem;
        margin-bottom: 0.6rem;
    }
}

/* Year Markers */
.timeline-year-marker {
    position: absolute;
    left: 50%;
    transform: translateX(-50%);
    background: #2c3e50;
    color: #fff;
    padding: 4px 15px;
    border-radius: 20px;
    font-weight: 600;
    font-size: 1rem;
    margin: -30px 0 20px;
    z-index: 3;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.institution-icon {
    font-size: 1.2em;
    margin-right: 0.5rem;
}

/* Mobile adjustments for year markers */
@media (max-width: 768px) {
    .timeline-year-marker {
        left: 30px;
        transform: none;
        font-size: 0.9rem;
        padding: 3px 12px;
        margin: -20px 0 15px;
    }

    .institution-icon {
        font-size: 1.1em;
    }
}

@media (max-width: 480px) {
    .timeline-year-marker {
        left: 20px;
        font-size: 0.85rem;
        padding: 2px 10px;
        margin: -15px 0 12px;
    }

    .institution-icon {
        font-size: 1em;
    }
} 

/* Presentations Section */
.section-header {
    text-align: center;
    margin-bottom: 2rem;
}

.section-description {
    color: #666;
    font-size: 1.1rem;
    margin-top: 0.5rem;
}

/* Controls */
.presentation-controls {
    background: #f8f9fa;
    padding: 1.5rem;
    border-radius: 8px;
    margin-bottom: 2rem;
}

.presentation-filters {
    display: flex;
    gap: 1rem;
    align-items: center;
    flex-wrap: wrap;
}

.filter-group {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.filter-group label {
    font-weight: 500;
    color: #2c3e50;
}

.filter-select {
    padding: 0.5rem;
    border: 1px solid #ddd;
    border-radius: 4px;
    background: white;
    min-width: 120px;
    font-size: 0.9rem;
}

.clear-filters-btn {
    padding: 0.5rem 1rem;
    background: #e9ecef;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 0.5rem;
    transition: background-color 0.2s;
}

.clear-filters-btn:hover {
    background: #dee2e6;
}

/* Stats */
.presentation-stats {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
    gap: 1.5rem;
    margin-top: 2rem;
    padding: 1.5rem;
    background: linear-gradient(135deg, #f8f9fa 0%, #ffffff 100%);
    border-radius: 12px;
    box-shadow: 0 2px 15px rgba(0,0,0,0.05);
}

.stat-item {
    text-align: center;
    padding: 1.5rem;
    background: white;
    border-radius: 10px;
    box-shadow: 0 4px 15px rgba(0,0,0,0.05);
    transition: all 0.3s ease;
    border: 1px solid rgba(52, 152, 219, 0.1);
    position: relative;
    overflow: hidden;
}

.stat-item::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 4px;
    background: linear-gradient(135deg, #3498db, #2ecc71);
    opacity: 0.7;
}

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

.stat-number {
    font-size: 2.5rem;
    font-weight: 700;
    color: #2c3e50;
    display: block;
    margin-bottom: 0.5rem;
    background: linear-gradient(135deg, #3498db, #2ecc71);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    line-height: 1.2;
}

.stat-label {
    font-size: 1rem;
    color: #6c757d;
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

@media (max-width: 768px) {
    .presentation-stats {
        grid-template-columns: 1fr;
        padding: 1rem;
    }

    .stat-item {
        padding: 1.2rem;
    }

    .stat-number {
        font-size: 2rem;
    }

    .stat-label {
        font-size: 0.9rem;
    }
}

@media (prefers-reduced-motion: reduce) {
    .stat-item {
        transform: none !important;
        transition: none !important;
    }
}

@media (prefers-contrast: high) {
    .stat-number {
        background: none;
        -webkit-text-fill-color: initial;
        color: #2c3e50;
    }

    .stat-item::before {
        background: #2c3e50;
    }
}

/* Presentations Content */
.presentations-content {
    display: flex;
    flex-direction: column;
    gap: 2rem;
}

.presentation-type {
    background: white;
    border-radius: 8px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.05);
    overflow: hidden;
}

.type-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1.5rem;
    background: #f8f9fa;
    border-bottom: 1px solid #dee2e6;
}

.type-header h3 {
    margin: 0;
    display: flex;
    align-items: center;
    gap: 0.5rem;
    color: #2c3e50;
}

/* Presentation Items */
.presentation-items {
    padding: 1.5rem;
}

.presentation-item {
    border: 1px solid #dee2e6;
    border-radius: 6px;
    padding: 1.5rem;
    margin-bottom: 1rem;
    transition: transform 0.2s, box-shadow 0.2s;
}

.presentation-item:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(0,0,0,0.1);
}

.presentation-meta {
    display: flex;
    gap: 1.5rem;
    margin-bottom: 1rem;
    font-size: 0.9rem;
    color: #6c757d;
}

.presentation-meta span {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.presentation-content h4 {
    color: #2c3e50;
    margin: 0 0 0.5rem 0;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.presentation-content h4 i {
    color: #3498db;
}

.presentation-content p {
    margin: 0;
    color: #2c3e50;
    line-height: 1.5;
}

/* Show More Button */
.show-more-btn {
    width: 100%;
    padding: 1rem;
    background: #2980b9;
    color: white;
    border: none;
    border-top: 1px solid #2980b9;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    transition: background-color 0.2s;
}

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

.show-more-btn i {
    transition: transform 0.2s;
}

.show-more-btn.showing-more i {
    transform: rotate(180deg);
}

/* No Results */
.no-results {
    text-align: center;
    padding: 3rem;
    background: white;
    border-radius: 8px;
    color: #6c757d;
}

.no-results i {
    font-size: 2rem;
    margin-bottom: 1rem;
}

/* Responsive Design */
@media (max-width: 768px) {
    .presentation-filters {
        flex-direction: column;
        align-items: stretch;
    }

    .filter-group {
        flex-direction: column;
        align-items: stretch;
    }

    .presentation-stats {
        flex-direction: column;
        gap: 1rem;
    }

    .stat-item {
        padding: 1rem;
        background: white;
        border-radius: 4px;
    }
}

/* Animations */
@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

.presentation-item {
    animation: fadeIn 0.3s ease-out;
}