:root {
            --primary-color: #2563eb;
            --text-dark: #1f2937;
            --text-medium: #4b5563;
            --text-light: #6b7280;
            --bg-light: #f9fafb;
            --border-color: #e5e7eb;
            --link-color: #2563eb;
            --link-hover: #1d4ed8;
            --tab-active: #2563eb;
        }

        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }

        html {
            scroll-behavior: smooth;
        }

        body {
            font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
            line-height: 1.6;
            color: var(--text-dark);
            background: white;
            font-size: 16px;
        }

        /* Container */
        .container {
            max-width: 1000px;
            margin: 0 auto;
            padding: 0 30px;
        }

        /* Navigation Tabs (at top) */
        .top-nav {
            border-bottom: 2px solid var(--border-color);
            background: white;
        }

        /* Header */
        header {
            padding: 50px 0 30px;
            border-bottom: 1px solid var(--border-color);
        }

        .header-content {
            display: flex;
            align-items: center;
            gap: 40px;
            margin-bottom: 25px;
        }

        .profile-photo {
            flex-shrink: 0;
        }

        .profile-photo img {
            width: 180px;
            height: 180px;
            border-radius: 50%;
            object-fit: cover;
            border: 3px solid var(--border-color);
        }

        .profile-photo .placeholder {
            width: 180px;
            height: 180px;
            border-radius: 50%;
            background: var(--bg-light);
            border: 3px solid var(--border-color);
            display: flex;
            align-items: center;
            justify-content: center;
            color: var(--text-light);
            font-size: 14px;
            text-align: center;
            padding: 20px;
        }

        .header-text {
            flex: 1;
        }

        header h1 {
            font-size: 2.5rem;
            font-weight: 700;
            margin-bottom: 8px;
            color: var(--text-dark);
        }

        header .subtitle {
            font-size: 1.15rem;
            color: var(--text-medium);
            margin-bottom: 18px;
            font-weight: 500;
        }

        .contact-links {
            display: flex;
            flex-wrap: wrap;
            gap: 18px;
            margin-top: 15px;
        }

        .contact-links a {
            color: var(--link-color);
            text-decoration: none;
            font-size: 0.95rem;
            transition: color 0.2s ease;
            display: inline-flex;
            align-items: center;
            gap: 6px;
        }

        .contact-links a:hover {
            color: var(--link-hover);
            text-decoration: underline;
        }

        .contact-links a i {
            font-size: 1rem;
        }

        /* Navigation Tabs */
        .nav-tabs {
            display: flex;
            gap: 5px;
            max-width: 1000px;
            margin: 0 auto;
            padding: 0 30px;
        }

        .nav-tabs button {
            padding: 12px 24px;
            background: none;
            border: none;
            font-size: 1rem;
            font-weight: 500;
            color: var(--text-medium);
            cursor: pointer;
            transition: all 0.2s ease;
            border-bottom: 3px solid transparent;
            font-family: inherit;
        }

        .nav-tabs button:hover {
            color: var(--text-dark);
            background: var(--bg-light);
        }

        .nav-tabs button.active {
            color: var(--tab-active);
            border-bottom-color: var(--tab-active);
        }

        /* Tab Content */
        .tab-content {
            display: none;
            padding: 50px 0;
        }

        .tab-content.active {
            display: block;
        }

        /* Section Styles */
        section {
            margin-bottom: 50px;
        }

        section h2 {
            font-size: 1.8rem;
            font-weight: 700;
            margin-bottom: 25px;
            color: var(--text-dark);
        }

        section h3 {
            font-size: 1.3rem;
            font-weight: 600;
            margin-top: 35px;
            margin-bottom: 20px;
            color: var(--text-dark);
        }

        /* Bio */
        .bio {
            color: var(--text-medium);
            line-height: 1.8;
            font-size: 1.05rem;
        }

        .bio p {
            margin-bottom: 18px;
        }

        .bio strong {
            color: var(--text-dark);
            font-weight: 600;
        }

        /* Timeline */
        .timeline {
            position: relative;
            padding-left: 35px;
            margin: 30px 0;
        }

        .timeline::before {
            content: '';
            position: absolute;
            left: 7px;
            top: 5px;
            bottom: 0;
            width: 2px;
            background: var(--border-color);
        }

        .timeline-item {
            position: relative;
            margin-bottom: 28px;
            padding-left: 20px;
        }

        .timeline-item::before {
            content: '';
            position: absolute;
            left: -32px;
            top: 6px;
            width: 14px;
            height: 14px;
            border-radius: 50%;
            background: white;
            border: 3px solid var(--primary-color);
            z-index: 1;
        }

        .timeline-item:first-child::before {
            background: var(--primary-color);
        }

        .timeline-year {
            font-weight: 600;
            color: var(--primary-color);
            font-size: 0.95rem;
            margin-bottom: 5px;
        }

        .timeline-content {
            color: var(--text-medium);
            line-height: 1.7;
        }

        .timeline-content strong {
            color: var(--text-dark);
            font-weight: 600;
        }


        /* News */
        .news-item {
            margin-bottom: 20px;
            display: flex;
            gap: 20px;
        }

        .news-date {
            flex-shrink: 0;
            width: 100px;
            color: var(--text-light);
            font-weight: 500;
            font-size: 0.95rem;
        }

        .news-content {
            color: var(--text-medium);
            line-height: 1.7;
        }

        /* Publications */
        .pub-subtabs {
            display: flex;
            gap: 8px;
            margin-bottom: 25px;
            flex-wrap: wrap;
        }

        .pub-subtabs button {
            padding: 8px 16px;
            background: white;
            border: 1px solid var(--border-color);
            border-radius: 6px;
            font-size: 0.9rem;
            font-weight: 500;
            color: var(--text-medium);
            cursor: pointer;
            transition: all 0.2s ease;
        }

        .pub-subtabs button:hover {
            background: var(--bg-light);
            border-color: var(--primary-color);
        }

        .pub-subtabs button.active {
            background: var(--primary-color);
            color: white;
            border-color: var(--primary-color);
        }

        .badge-legend {
            background: var(--bg-light);
            padding: 20px 25px;
            border-radius: 8px;
            margin-bottom: 30px;
        }

        .badge-legend h4 {
            font-size: 1rem;
            font-weight: 600;
            margin-bottom: 12px;
            color: var(--text-dark);
        }

        .badge-legend-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
            gap: 10px;
        }

        .badge-legend-item {
            display: flex;
            align-items: center;
            gap: 10px;
        }

        .pub-list {
            list-style: none;
        }

        .pub-item {
            margin-bottom: 20px;
            padding-bottom: 20px;
            border-bottom: 1px solid #f3f4f6;
        }

        .pub-item:last-child {
            border-bottom: none;
        }

        .pub-number {
            display: inline-block;
            color: var(--text-light);
            font-weight: 500;
            margin-right: 8px;
            font-size: 0.9rem;
            vertical-align: top;
        }

        .pub-header {
            display: flex;
            align-items: flex-start;
            gap: 8px;
            margin-bottom: 5px;
        }

        .pub-badges {
            display: inline-flex;
            gap: 4px;
            flex-wrap: wrap;
        }

        .badge {
            display: inline-block;
            padding: 2px 7px;
            border-radius: 3px;
            font-size: 0.65rem;
            font-weight: 600;
            color: white;
            margin-right: 4px;
            font-family: 'Roboto Mono', monospace;
            text-transform: uppercase;
        }

        .badge-llm { background-color: #3b82f6; }
        .badge-sys { background-color: #1f2937; }
        .badge-opt { background-color: #dc2626; }
        .badge-rl { background-color: #7c3aed; }
        .badge-ts { background-color: #f97316; }
        .badge-ml { background-color: #84cc16; }
        .badge-uq { background-color: #14b8a6; }

        .pub-title {
            font-weight: 600;
            color: var(--text-dark);
            font-size: 0.98rem;
            line-height: 1.4;
            display: inline;
        }

        .pub-authors {
            color: var(--text-medium);
            font-size: 0.9rem;
            margin-bottom: 3px;
        }

        .pub-authors .highlight {
            font-weight: 600;
            color: var(--text-dark);
        }

        .pub-venue-line {
            display: flex;
            align-items: center;
            gap: 12px;
            flex-wrap: wrap;
        }

        .pub-venue {
            color: var(--text-light);
            font-style: italic;
            font-size: 0.88rem;
        }

        .pub-venue strong {
            color: var(--text-medium);
            font-weight: 600;
        }

        .pub-links {
            display: inline-flex;
            gap: 12px;
        }

        .pub-links a {
            color: var(--link-color);
            text-decoration: none;
            font-size: 0.88rem;
        }

        .pub-links a:hover {
            text-decoration: underline;
        }

        .pub-note {
            color: #dc2626;
            font-weight: 600;
            font-size: 0.9rem;
            margin-top: 5px;
        }

        /* Mentorship */
        .mentee-grid {
            display: grid;
            grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
            gap: 15px;
            margin-top: 20px;
        }

        .mentee-item {
            padding: 15px;
            background: var(--bg-light);
            border-radius: 6px;
            border-left: 3px solid var(--primary-color);
        }

        .mentee-name {
            font-weight: 600;
            color: var(--text-dark);
            margin-bottom: 5px;
        }

        .mentee-institution {
            color: var(--text-medium);
            font-size: 0.9rem;
            margin-bottom: 3px;
        }

        .mentee-placement {
            color: var(--primary-color);
            font-size: 0.9rem;
            font-weight: 500;
        }

        /* Footer */
        footer {
            padding: 40px 0;
            text-align: center;
            color: var(--text-light);
            font-size: 0.9rem;
            border-top: 1px solid var(--border-color);
        }

        /* Responsive */
        @media (max-width: 768px) {
            .header-content {
                flex-direction: column;
                text-align: center;
            }

            .profile-photo img,
            .profile-photo .placeholder {
                width: 150px;
                height: 150px;
            }

            header h1 {
                font-size: 2rem;
            }

            .nav-tabs {
                overflow-x: auto;
                flex-wrap: nowrap;
            }

            .nav-tabs button {
                padding: 10px 16px;
                font-size: 0.9rem;
                white-space: nowrap;
            }

            section h2 {
                font-size: 1.5rem;
            }

            .news-item {
                flex-direction: column;
                gap: 5px;
            }

            .news-date {
                width: auto;
            }

            .badge-legend-grid {
                grid-template-columns: 1fr;
            }

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