.academic-gradient {
            background: linear-gradient(to right, #dc2626, #b91c1c); /* Red to dark red */
        }
        .orange-gradient {
            background: linear-gradient(to right, #ef4444, #dc2626); /* Light red to red */
        }
        .subtle-gradient {
            background: linear-gradient(to bottom, #fef2f2, #ffffff); /* Light red tint to white */
        }
        .academic-card {
            box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
            border-radius: 8px;
            border: 1px solid #fee2e2;
            background: white;
            opacity: 0;
            transform: translateY(20px);
            animation: fadeInUp 0.6s ease-out forwards;
        }
        .academic-heading {
            font-weight: bold;
            color: #111827;
        }
        .academic-body {
            color: #4b5563;
        }
        .academic-subheading {
            color: #6b7280;
        }
        /* Shadow elegant */
        :root {
            --shadow-elegant: 0 4px 20px rgba(0, 0, 0, 0.05);
        }
        /* Line clamp simulation for older browsers */
        .line-clamp-2 {
            overflow: hidden;
            display: -webkit-box;
            -webkit-box-orient: vertical;
            -webkit-line-clamp: 2;
        }
        .line-clamp-3 {
            overflow: hidden;
            display: -webkit-box;
            -webkit-box-orient: vertical;
            -webkit-line-clamp: 3;
        }
        .line-clamp-1 {
            overflow: hidden;
            display: -webkit-box;
            -webkit-box-orient: vertical;
            -webkit-line-clamp: 1;
        }
        /* New Filter Section Styles */
        .filter-section {
            background: linear-gradient(to bottom, #ffffff, #fef2f2);
            border-radius: 16px;
            padding: 2rem;
            box-shadow: 0 6px 24px rgba(0, 0, 0, 0.08);
            border: 2px solid #fee2e2;
        }
        .search-container {
            position: relative;
            transition: all 0.3s ease;
        }
        .search-input {
            background: white;
            border: 2px solid #ef4444;
            border-radius: 12px;
            padding: 0.75rem 1rem 0.75rem 3rem;
            font-size: 1rem;
            width: 100%;
            transition: all 0.3s ease;
        }
        .search-input:focus {
            border-color: #dc2626;
            box-shadow: 0 0 0 4px rgba(220, 38, 38, 0.1), 0 0 8px rgba(220, 38, 38, 0.3);
            outline: none;
            animation: glow 1.5s ease-in-out infinite;
        }
        .filter-scroll {
            display: flex;
            overflow-x: auto;
            gap: 0.75rem;
            padding-bottom: 0.5rem;
            scrollbar-width: thin;
            scrollbar-color: #ef4444 #fee2e2;
        }
        .filter-scroll::-webkit-scrollbar {
            height: 8px;
        }
        .filter-scroll::-webkit-scrollbar-track {
            background: #fee2e2;
            border-radius: 4px;
        }
        .filter-scroll::-webkit-scrollbar-thumb {
            background: #ef4444;
            border-radius: 4px;
        }
        .filter-card {
            flex: 0 0 auto;
            padding: 0.75rem 1.5rem;
            border-radius: 10px;
            background: #fef2f2;
            border: 1px solid #ef4444;
            font-size: 0.9rem;
            font-weight: 500;
            color: #b91c1c;
            cursor: pointer;
            transition: all 0.3s ease;
            position: relative;
            display: flex;
            align-items: center;
            gap: 0.5rem;
            transform: scale(1);
        }
        .filter-card:hover {
            transform: scale(1.05) translateY(-3px);
            box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
            background: #fee2e2;
        }
        .filter-card.active {
            background: linear-gradient(to right, #dc2626, #b91c1c);
            color: white;
            border-color: transparent;
            box-shadow: 0 6px 16px rgba(220, 38, 38, 0.3);
            transform: scale(1.05);
        }
        .filter-card svg {
            flex-shrink: 0;
        }
        /* Feature cards staggered animation */
        .feature-card {
            opacity: 0;
            transform: translateY(20px);
            animation: fadeInUp 0.6s ease-out forwards;
        }
        .feature-card:nth-child(1) { animation-delay: 0.1s; }
        .feature-card:nth-child(2) { animation-delay: 0.2s; }
        .feature-card:nth-child(3) { animation-delay: 0.3s; }
        /* Button hover animation */
        .academic-btn {
            transition: transform 0.2s ease, background-color 0.3s ease;
        }
        .academic-btn:hover {
            transform: scale(1.05);
            background-color: #b91c1c;
        }
        /* Paper detail section animation */
        #paper-detail-section {
            opacity: 0;
            transform: translateX(20px);
            transition: opacity 0.5s ease, transform 0.5s ease;
        }
        #paper-detail-section:not(.hidden) {
            opacity: 1;
            transform: translateX(0);
        }
        /* Keyframes for animations */
        @keyframes fadeInUp {
            from {
                opacity: 0;
                transform: translateY(20px);
            }
            to {
                opacity: 1;
                transform: translateY(0);
            }
        }
        @keyframes glow {
            0%, 100% {
                box-shadow: 0 0 0 4px rgba(220, 38, 38, 0.1), 0 0 8px rgba(220, 38, 38, 0.3);
            }
            50% {
                box-shadow: 0 0 0 4px rgba(220, 38, 38, 0.2), 0 0 12px rgba(220, 38, 38, 0.5);
            }
        }