* {
            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;
        }
        
        .container {
            max-width: 1200px;
            margin: 0 auto;
            padding: 20px;
        }
        
        header {
            background: linear-gradient(135deg, #1a2a6c, #2a3a7c);
            color: white;
            padding: 30px 0;
            text-align: center;
            border-radius: 0 0 10px 10px;
            box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
            margin-bottom: 30px;
        }
        
        .logo {
            display: flex;
            align-items: center;
            justify-content: center;
            margin-bottom: 15px;
        }
        
        .logo-icon {
            font-size: 2.5rem;
            margin-right: 15px;
        }
        
        /* Navigation Menu Styles */
        .main-nav {
            background: #fff;
            border-radius: 8px;
            box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
            margin-bottom: 30px;
        }
        
        .nav-menu {
            display: flex;
            list-style: none;
            justify-content: center;
            flex-wrap: wrap;
        }
        
        .nav-menu li {
            margin: 0;
        }
        
        .nav-menu a {
            display: block;
            padding: 15px 25px;
            text-decoration: none;
            color: #333;
            font-weight: 500;
            transition: all 0.3s ease;
            border-bottom: 3px solid transparent;
        }
        
        .nav-menu a:hover {
            background-color: #f0f5ff;
            color: #1a2a6c;
            border-bottom: 3px solid #1a2a6c;
        }
        
        .nav-menu .current a {
            color: #1a2a6c;
            border-bottom: 3px solid #1a2a6c;
            background-color: #f0f5ff;
        }
        
        /* Responsive navigation */
        @media (max-width: 768px) {
            .nav-menu {
                flex-direction: column;
            }
            
            .nav-menu li {
                width: 100%;
                text-align: center;
            }
        }
        
        .professor-info {
            background: white;
            padding: 25px;
            border-radius: 8px;
            box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
            margin-bottom: 30px;
            display: flex;
            align-items: center;
            gap: 20px;
        }
        
        .professor-avatar {
            font-size: 4rem;
        }
        
        .dashboard-section {
            background: white;
            padding: 25px;
            border-radius: 8px;
            box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
            margin-bottom: 30px;
        }
        
        .section-title {
            font-size: 1.5rem;
            color: #1a2a6c;
            margin-bottom: 20px;
            padding-bottom: 10px;
            border-bottom: 2px solid #e0e7ff;
        }
        
        .publication-list {
            list-style-type: none;
        }
        
        .publication-list li {
            margin-bottom: 20px;
            padding-bottom: 20px;
            border-bottom: 1px solid #eee;
        }
        
        .publication-list li:last-child {
            border-bottom: none;
        }
        
        .publication-title {
            font-weight: 600;
            color: #2c3e50;
            margin-bottom: 5px;
        }
        
        .publication-authors {
            color: #555;
            margin-bottom: 5px;
            font-style: italic;
        }
        
        .publication-venue {
            color: #666;
            margin-bottom: 5px;
        }
        
        .publication-links {
            margin-top: 10px;
        }
        
        .btn-pdf {
            display: inline-block;
            background: #dc3545;
            color: white;
            padding: 5px 12px;
            border-radius: 4px;
            text-decoration: none;
            font-size: 0.85rem;
            transition: all 0.3s ease;
        }
        
        .btn-pdf:hover {
            background: #c82333;
            transform: translateY(-2px);
            box-shadow: 0 3px 8px rgba(0,0,0,0.2);
        }
        /* Inactive PDF button style */
.btn-pdf.inactive {
    background: #6c757d;
    color: #adb5bd;
    cursor: not-allowed;
    opacity: 0.6;
    pointer-events: none;
    position: relative;
}

.btn-pdf.inactive::after {
    content: "Not Available";
    position: absolute;
    top: -35px;
    left: 50%;
    transform: translateX(-50%);
    background: #495057;
    color: white;
    padding: 5px 10px;
    border-radius: 4px;
    font-size: 0.7rem;
    white-space: nowrap;
    opacity: 0;
    transition: opacity 0.3s;
    pointer-events: none;
}

.btn-pdf.inactive:hover::after {
    opacity: 1;
}

.btn-pdf.inactive:hover {
    background: #6c757d;
    transform: none;
    box-shadow: none;
}
        
        .publication-category {
            margin-top: 40px;
        }
        
        .publication-category:first-child {
            margin-top: 0;
        }
        
        footer {
            text-align: center;
            padding: 20px 0;
            margin-top: 40px;
            border-top: 1px solid #e0e7ff;
            color: #666;
            font-size: 0.9rem;
        }
        
        footer a {
            color: #1a2a6c;
            text-decoration: none;
            margin: 0 5px;
        }
        
        footer a:hover {
            text-decoration: underline;
        }