/* Publications Section */
.publications {
    background-color: var(--light-color);
}

/* Filter Buttons */
.filter-container {
    margin-bottom: 3rem;
    overflow-x: auto;
    padding-bottom: 10px;
    -webkit-overflow-scrolling: touch;
}

.filter-buttons {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    justify-content: center;
    min-width: min-content;
    padding: 5px 0;
}

.filter-btn {
    padding: 10px 20px;
    background-color: var(--white);
    border: 1px solid var(--gray-light);
    border-radius: 30px;
    font-family: var(--font-primary);
    font-weight: 500;
    font-size: 0.95rem;
    color: var(--gray-dark);
    cursor: pointer;
    transition: var(--transition);
    white-space: nowrap;
    outline: none;
}

.filter-btn:hover {
    background-color: var(--gray-light);
    color: var(--primary-color);
    border-color: var(--gray-medium);
}

.filter-btn.active {
    background-color: var(--primary-color);
    color: var(--white);
    border-color: var(--primary-color);
}

/* Publications Grid */
.publications-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
    gap: 2rem;
    margin-bottom: 3rem;
}

.publication-card {
    background-color: var(--white);
    border-radius: var(--border-radius);
    overflow: hidden;
    box-shadow: var(--box-shadow);
    transition: var(--transition);
    display: flex;
    flex-direction: column;
    height: 100%;
    opacity: 0;
    transform: translateY(20px);
    animation: fadeInUp 0.5s ease forwards;
}

.publication-card:nth-child(1) { animation-delay: 0.1s; }
.publication-card:nth-child(2) { animation-delay: 0.2s; }
.publication-card:nth-child(3) { animation-delay: 0.3s; }
.publication-card:nth-child(4) { animation-delay: 0.4s; }
.publication-card:nth-child(5) { animation-delay: 0.5s; }
.publication-card:nth-child(6) { animation-delay: 0.6s; }

@keyframes fadeInUp {
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.publication-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 30px rgba(0, 0, 0, 0.1);
}

.publication-header {
    padding: 1.5rem 1.5rem 0.5rem;
}

.publication-category {
    display: inline-block;
    padding: 4px 12px;
    background-color: rgba(52, 152, 219, 0.1);
    color: var(--secondary-color);
    border-radius: 30px;
    font-size: 0.8rem;
    font-weight: 600;
    margin-bottom: 1rem;
    font-family: var(--font-primary);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.publication-title {
    font-size: 1.3rem;
    line-height: 1.4;
    color: var(--primary-color);
    margin-bottom: 1rem;
    font-family: var(--font-secondary);
    font-weight: 600;
}

.publication-body {
    padding: 0 1.5rem;
    flex-grow: 1;
}

.publication-abstract {
    font-size: 0.95rem;
    line-height: 1.6;
    color: var(--gray-dark);
    margin-bottom: 1.5rem;
    
    /* Modern approach with good browser support */
    display: -webkit-box;
    -webkit-line-clamp: 4;
    -webkit-box-orient: vertical;
    overflow: hidden;
    text-overflow: ellipsis;
    
    /* Standard line-clamp (still experimental but gaining support) */
    line-clamp: 4;
    box-orient: vertical;
}

/* Fallback for browsers that don't support line-clamp */
@supports not ((-webkit-line-clamp: 4) or (line-clamp: 4)) {
    .publication-abstract {
        max-height: 6.4em; /* 4 lines * 1.6 line-height */
        overflow: hidden;
        position: relative;
    }
    
    .publication-abstract::after {
        content: '';
        position: absolute;
        bottom: 0;
        right: 0;
        width: 30%;
        height: 1.6em;
        background: linear-gradient(to right, rgba(255, 255, 255, 0), var(--white) 50%);
    }
}

.publication-footer {
    padding: 1rem 1.5rem 1.5rem;
    display: flex;
    gap: 1rem;
    border-top: 1px solid var(--gray-light);
}

.publication-link {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    text-decoration: none;
    color: var(--secondary-color);
    font-weight: 500;
    font-size: 0.9rem;
    transition: var(--transition);
    padding: 8px 15px;
    border-radius: var(--border-radius);
    background-color: rgba(52, 152, 219, 0.05);
    flex: 1;
    justify-content: center;
}

.publication-link:hover {
    background-color: rgba(52, 152, 219, 0.15);
    color: var(--primary-color);
}

.publication-link i {
    font-size: 0.9rem;
}

/* Load More Button */
.load-more-container {
    text-align: center;
    margin-top: 2rem;
}

#loadMoreBtn {
    padding: 12px 30px;
    font-size: 1rem;
}

/* No publications message */
.no-publications {
    grid-column: 1 / -1;
    text-align: center;
    padding: 60px 20px;
    background-color: var(--white);
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
}

.no-publications i {
    font-size: 3rem;
    color: var(--gray-medium);
    margin-bottom: 1.5rem;
}

.no-publications h3 {
    color: var(--gray-dark);
    margin-bottom: 0.5rem;
}

.no-publications p {
    color: var(--gray-medium);
    margin-bottom: 0;
}

/* PDF Modal */
.pdf-modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.8);
    z-index: 2000;
    justify-content: center;
    align-items: center;
    padding: 20px;
    
}

.pdf-modal.show {
    opacity: 1;
}

.pdf-modal-content {
    background-color: var(--white);
    border-radius: var(--border-radius);
    width: 100%;
    max-width: 1000px;
    max-height: 90vh;
    display: flex;
    flex-direction: column;
    overflow: hidden;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
    transform: translateY(20px);
    transition: transform 0.3s ease;
}

.pdf-modal.show .pdf-modal-content {
    transform: translateY(0);
}

.pdf-modal-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1.5rem 2rem;
    background-color: var(--primary-color);
    color: var(--white);
    flex-shrink: 0;
}

.pdf-modal-header h3 {
    font-size: 1.5rem;
    margin-bottom: 0;
    color: var(--white);
    flex: 1;
    padding-right: 20px;
    font-family: var(--font-secondary);
    font-weight: 600;
}

.pdf-modal-close {
    background: none;
    border: none;
    color: var(--white);
    font-size: 1.5rem;
    cursor: pointer;
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    transition: var(--transition);
    flex-shrink: 0;
}

.pdf-modal-close:hover {
    background-color: rgba(255, 255, 255, 0.1);
}

.pdf-modal-body {
    flex: 1;
    overflow-y: auto;
    padding: 2rem;
}

.pdf-viewer-container {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.pdf-actions {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
}

.pdf-viewer {
    width: 100%;
    height: 600px;
    border: 1px solid var(--gray-light);
    border-radius: var(--border-radius);
    background-color: var(--light-color);
}
.pdf-viewer iframe {
    width: 100%;
    height: 100%;
    border: none;
    display: block;
}

@media (max-width: 768px) {
    .pdf-viewer {
        height: 60vh;
    }
}

.pdf-placeholder {
    width: 100%;
    height: 100%;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    background-color: var(--light-color);
    color: var(--gray-medium);
    padding: 20px;
    text-align: center;
}

.pdf-placeholder i {
    font-size: 4rem;
    margin-bottom: 1rem;
    color: var(--accent-color);
}

.pdf-placeholder p {
    font-size: 1.2rem;
    color: var(--primary-color);
    margin-bottom: 0.5rem;
    font-weight: 600;
}

.pdf-placeholder-text {
    font-size: 0.9rem;
    max-width: 300px;
    text-align: center;
    margin-top: 0.5rem;
    color: var(--gray-dark);
    line-height: 1.5;
}
/* Add to publications.css */
.pdf-controls {
    display: flex;
    align-items: center;
    gap: 10px;
    margin-left: auto;
}

#pdfPageNum {
    font-size: 0.9rem;
    color: var(--gray-dark);
    font-weight: 500;
}

#pdfCanvas {
    width: 100%;
    height: 100%;
    display: block;
}

/* Responsive for Publications */
@media (max-width: 992px) {
    .publications-grid {
        grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    }
    
    .pdf-viewer {
        height: 500px;
    }
}

@media (max-width: 768px) {
    .publications-grid {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }
    
    .filter-buttons {
        justify-content: flex-start;
    }
    
    .pdf-modal-content {
        max-height: 80vh;
    }
    
    .pdf-viewer {
        height: 400px;
    }
    
    .pdf-modal-header {
        padding: 1.2rem 1.5rem;
    }
    
    .pdf-modal-body {
        padding: 1.5rem;
    }
}

@media (max-width: 576px) {
    .publication-footer {
        flex-direction: column;
        gap: 0.5rem;
    }
    
    .publication-link {
        justify-content: center;
    }
    
    .pdf-viewer {
        height: 300px;
    }
    
    .pdf-actions {
        flex-direction: column;
    }
    
    .pdf-actions .btn {
        width: 100%;
        text-align: center;
    }
}