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

        :root {
            --primary: #18181b;
            --primary-light: #27272a;
            --secondary: #52525b;
            --accent: #4f46e5;
            --accent-hover: #4338ca;
            --bg: #f4f4f5;
            --white: #ffffff;
            --text: #27272a;
            --text-light: #52525b;
            --border: #e4e4e7;
            --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
            --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
            --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
            --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1), 0 8px 10px -6px rgb(0 0 0 / 0.1);
        }

        body {
            font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
            background: #fbfbfc;
            color: var(--text);
            line-height: 1.6;
            font-size: 15px;
            min-height: 100vh;
            padding-bottom: 60px;
            -webkit-font-smoothing: antialiased;
            text-rendering: optimizeLegibility;
        }

        .header {
            background: var(--primary);
            position: sticky;
            top: 0;
            z-index: 100;
            box-shadow: var(--shadow-md);
            border-bottom: 1px solid rgba(255, 255, 255, 0.05);
        }

        .header-content {
            max-width: 1100px;
            margin: 0 auto;
            display: flex;
            align-items: center;
            justify-content: space-between;
            padding: 0 20px;
        }

        .header-brand {
            color: var(--white);
            font-size: 22px;
            letter-spacing: -0.5px;
            font-weight: 700;
            padding: 16px 0;
        }

        .nav-tabs {
            display: flex;
            gap: 8px;
            padding: 8px 0;
        }

        .nav-tab {
            padding: 8px 16px;
            border: none;
            background: transparent;
            border-radius: 4px;
            font-family: inherit;
            font-size: 14px;
            font-weight: 500;
            color: rgba(255, 255, 255, 0.7);
            cursor: pointer;
            transition: all 0.2s ease;
            letter-spacing: 0.5px;
        }

        .nav-tab:hover {
            color: var(--white);
            background: transparent;
        }

        .nav-tab.active {
            color: var(--white);
            background: rgba(255, 255, 255, 0.15);
        }

        .main-container {
            max-width: 1100px;
            margin: 40px auto;
            padding: 0 20px;
        }

        .page {
            display: none;
        }

        .page.active {
            display: block;
        }

        .cv-container {
            display: flex;
            background: var(--white);
            box-shadow: var(--shadow-xl);
            border-radius: 8px;
            overflow: hidden;
            border: 1px solid rgba(0,0,0,0.05);
        }

        .sidebar {
            width: 320px;
            flex-shrink: 0;
            background: var(--primary);
            color: var(--white);
            padding: 40px 30px;
        }

        .profile-section {
            text-align: center;
            margin-bottom: 30px;
            padding-bottom: 30px;
            border-bottom: 1px solid rgba(255, 255, 255, 0.05);
        }

        .profile-photo {
            width: 120px;
            height: 120px;
            border-radius: 50%;
            background: var(--white);
            margin: 0 auto 20px;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 40px;
            font-weight: 600;
            color: var(--primary);
            box-shadow: var(--shadow-sm);
            border: 2px solid var(--white);
            letter-spacing: 1px;
        }

        .profile-name {
            font-size: 26px;
            font-weight: 700;
            letter-spacing: -0.5px;
            margin-bottom: 6px;
        }

        .profile-title {
            font-size: 14px;
            opacity: 0.9;
            font-weight: 500;
            letter-spacing: 0.5px;
        }

        .header-social {
            display: flex;
            align-items: center;
            gap: 8px;
        }

        .social-link {
            display: flex;
            align-items: center;
            justify-content: center;
            width: 36px;
            height: 36px;
            border-radius: 4px;
            transition: background 0.2s ease;
        }

        .social-link:hover {
            background: rgba(255, 255, 255, 0.15);
        }

        .social-icon {
            object-fit: contain;
            border-radius: 4px;
        }
        .social-icon.linkedin {
            width: 34px;
            height: 34px;
        }
        .social-icon.github {
            width: 26px;
            height: 26px;
            filter: brightness(1.8) contrast(1.2);
        }

        .cv-download-btn {
            position: absolute;
            top: 16px;
            right: 16px;
            padding: 8px 14px;
            background: var(--primary);
            color: #fff;
            border: 1px solid rgba(0, 0, 0, 0.1);
            border-radius: 4px;
            font-size: 13px;
            font-weight: 500;
            cursor: pointer;
            transition: all 0.2s ease;
            box-shadow: var(--shadow-sm);
            z-index: 10;
        }

        .cv-download-btn:hover {
            background: var(--primary-light);
            transform: translateY(-1px);
            box-shadow: var(--shadow-md);
        }

        .sidebar-section {
            margin-bottom: 30px;
        }

        .sidebar-title {
            font-size: 12px;
            font-weight: 700;
            text-transform: uppercase;
            letter-spacing: 1.5px;
            margin-bottom: 18px;
            opacity: 0.8;
            color: var(--white);
        }

        .contact-item {
            display: flex;
            align-items: center;
            gap: 12px;
            margin-bottom: 12px;
            font-size: 14px;
        }

        .contact-item a {
            color: rgba(255, 255, 255, 0.85);
            text-decoration: none;
            transition: color 0.2s ease;
        }

        .contact-item a:hover {
            color: #fff;
            text-decoration: none;
            text-shadow: 0 0 10px rgba(255,255,255,0.3);
        }

        .contact-logo-wrapper {
            width: 36px;
            height: 36px;
            display: flex;
            align-items: center;
            justify-content: center;
            flex-shrink: 0;
        }

        .contact-social-logo {
            object-fit: contain;
            border-radius: 4px;
        }

        .contact-social-logo.linkedin {
            width: 34px;
            height: 34px;
        }

        .contact-social-logo.github {
            width: 26px;
            height: 26px;
        }

        .experience-logo {
            width: 50px;
            height: 50px;
            object-fit: contain;
            border-radius: 8px;
            background: transparent;
            padding: 6px;
        }

        .academic-item {
            display: flex;
            gap: 16px;
            padding-bottom: 20px;
            margin-bottom: 20px;
            border-bottom: 2px solid rgba(0,0,0,0.08);
        }

        .academic-item:last-child {
            border-bottom: none;
            margin-bottom: 0;
            padding-bottom: 0;
        }

        .academic-item .experience-date {
            width: 100px;
            flex-shrink: 0;
        }

        .contact-icon-svg {
            width: 20px;
            height: 20px;
            opacity: 0.7;
            flex-shrink: 0;
            color: var(--white);
        }

        .skill-tag {
            display: inline-block;
            background: transparent;
            border: 1px solid rgba(255, 255, 255, 0.3);
            padding: 4px 10px;
            border-radius: 4px;
            font-size: 13px;
            margin: 4px 4px 4px 0;
            color: rgba(255,255,255,0.9);
            transition: all 0.2s ease;
        }

        .skill-tag:hover {
            background: rgba(255, 255, 255, 0.2);
            transform: translateY(-1px);
        }

        .skill-tag.primary {
            background: rgba(255, 255, 255, 0.2);
            color: #fff;
            border-color: rgba(255, 255, 255, 0.4);
        }

        .main-content {
            flex-grow: 1;
            padding: 55px 65px;
            background: var(--white);
        }

        .main-content a {
            color: var(--accent);
            text-decoration: none;
            transition: color 0.2s ease;
        }

        .main-content a:hover {
            color: var(--accent-hover);
            text-decoration: underline;
            color: var(--primary);
        }

        .section {
            margin-bottom: 45px;
        }

        .section:last-child {
            margin-bottom: 0;
        }

        .section-header {
            margin-bottom: 20px;
            padding-bottom: 8px;
            border-bottom: 2px solid var(--primary);
            display: inline-block;
        }

        

        .section-title {
            font-size: 22px;
            letter-spacing: -0.5px;
            font-weight: 700;
            color: var(--primary);
            text-transform: uppercase;
        }

        .experience-item {
            display: flex;
            gap: 20px;
            padding-bottom: 30px;
            margin-bottom: 30px;
            border-bottom: 2px solid rgba(0,0,0,0.08);
            align-items: start;
        }

        .experience-item:last-child {
            border-bottom: none;
            margin-bottom: 0;
            padding-bottom: 0;
        }

        .experience-logo-block {
            width: 90px;
            flex-shrink: 0;
            display: flex;
            flex-direction: column;
            align-items: center;
            gap: 8px;
        }

        .experience-logo {
            width: 80px;
            height: 80px;
            object-fit: contain;
            border-radius: 6px;
            background: transparent;
            padding: 4px;
        }

        .experience-date-block {
            text-align: center;
            font-size: 13px;
            color: var(--text-light);
            font-weight: 500;
        }

        .experience-date-block .city {
            display: block;
            font-size: 12px;
            opacity: 0.8;
            margin-top: 2px;
            font-weight: 400;
        }

        .experience-content h3 {
            font-size: 18px;
            font-weight: 600;
            letter-spacing: -0.2px;
            color: var(--text);
            margin-bottom: 4px;
        }

        .experience-company {
            font-size: 15px;
            color: var(--accent);
            font-weight: 500;
            margin-bottom: 12px;
        }

        .experience-description {
            font-size: 15px;
            color: var(--text-light);
            line-height: 1.6;
        }

        .education-item {
            display: flex;
            gap: 20px;
            padding-bottom: 24px;
            margin-bottom: 24px;
            border-bottom: 2px solid rgba(0,0,0,0.08);
        }

        .education-item:last-child {
            border-bottom: none;
            margin-bottom: 0;
            padding-bottom: 0;
        }

        .education-item .experience-date {
            width: 140px;
            flex-shrink: 0;
            font-weight: 500;
            color: var(--text-light);
        }

        .lang-item {
            display: flex;
            justify-content: space-between;
            align-items: center;
            padding: 12px 0;
            border-bottom: 1px solid rgba(255, 255, 255, 0.05);
        }

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

        .lang-name {
            font-weight: 500;
        }

        .lang-level {
            font-size: 13px;
            color: rgba(255, 255, 255, 0.7);
        }

        .interests {
            display: flex;
            flex-wrap: wrap;
            gap: 12px;
        }

        .interest-tag {
            background: var(--white);
            border: 1px solid rgba(0,0,0,0.08);
            padding: 6px 14px;
            border-radius: 4px;
            font-size: 13px;
            color: var(--text);
            box-shadow: var(--shadow-sm);
            transition: all 0.2s ease;
        }
        
        .interest-tag:hover {
            border-color: rgba(0,0,0,0.3);
            color: var(--primary);
            transform: translateY(-1px);
        }

        .articles-page {
            background: var(--white);
            box-shadow: var(--shadow-xl);
            border-radius: 8px;
            padding: 50px;
            border: 1px solid rgba(0,0,0,0.05);
        }

        .articles-page-header {
            display: flex;
            align-items: center;
            gap: 12px;
            margin-bottom: 30px;
            padding-bottom: 20px;
            border-bottom: 2px solid rgba(0,0,0,0.08);
        }

        .articles-grid {
            display: grid;
            grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
            gap: 24px;
        }

        .article-card {
            background: var(--white);
            border: 1px solid rgba(0,0,0,0.08);
            border-radius: 6px;
            overflow: hidden;
            cursor: pointer;
            transition: all 0.3s ease;
            box-shadow: var(--shadow-sm);
        }

        .article-card:hover {
            transform: translateY(-4px);
            box-shadow: var(--shadow-lg);
            border-color: rgba(0, 0, 0, 0.2);
        }

        .article-image {
            width: 100%;
            max-height: 180px;
            object-fit: contain;
            background: var(--primary-light);
        }

        .article-image.placeholder {
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 48px;
            color: rgba(255, 255, 255, 0.5);
        }

        .article-body {
            padding: 20px;
        }

        .article-title {
            font-size: 18px;
            font-weight: 600;
            color: var(--text);
            margin-bottom: 8px;
            line-height: 1.4;
        }

        .article-description {
            font-size: 14px;
            color: var(--text-light);
            line-height: 1.6;
            display: -webkit-box;
            -webkit-line-clamp: 3;
            -webkit-box-orient: vertical;
            overflow: hidden;
        }

        .article-meta {
            display: flex;
            align-items: center;
            gap: 12px;
            margin-top: 12px;
            font-size: 12px;
            color: var(--text-light);
        }

        .article-date {
            display: flex;
            align-items: center;
            gap: 4px;
        }

        .article-read-more {
            color: var(--accent);
            font-weight: 500;
            margin-left: auto;
        }

        .modal-overlay {
            display: none;
            position: fixed;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            background: rgba(0, 0, 0, 0.6);
            z-index: 1000;
            justify-content: center;
            align-items: flex-start;
            padding: 40px 20px;
            overflow-y: auto;
        }

        .modal-overlay.active {
            display: flex;
        }

        .modal {
            background: var(--white);
            border-radius: 8px;
            max-width: 800px;
            width: 100%;
            margin: auto;
            position: relative;
        }

        .modal-close {
            position: absolute;
            top: 16px;
            right: 16px;
            width: 40px;
            height: 40px;
            border: none;
            background: #fbfbfc;
            border-radius: 50%;
            cursor: pointer;
            font-size: 22px;
            letter-spacing: -0.5px;
            display: flex;
            align-items: center;
            justify-content: center;
            z-index: 10;
            transition: background 0.2s;
        }

        .modal-close:hover {
            background: var(--border);
        }

        .modal-image {
            width: 100%;
            height: 350px;
            object-fit: cover;
            border-radius: 16px 16px 0 0;
        }

        .modal-image.placeholder {
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 64px;
            color: rgba(255, 255, 255, 0.3);
            background: var(--primary-light);
        }

        .modal-body {
            padding: 40px;
        }

        .modal-title {
            font-size: 28px;
            font-weight: 700;
            color: var(--text);
            margin-bottom: 16px;
            line-height: 1.3;
        }

        .modal-meta {
            font-size: 13px;
            color: var(--text-light);
            margin-bottom: 24px;
            padding-bottom: 24px;
            border-bottom: 2px solid rgba(0,0,0,0.08);
        }

        .modal-content {
            font-size: 15px;
            color: var(--text);
            line-height: 1.8;
        }

        .modal-content h1, .modal-content h2, .modal-content h3 {
            margin-top: 24px;
            margin-bottom: 12px;
            color: var(--primary);
        }

        .modal-content h2 {
            font-size: 22px;
            letter-spacing: -0.5px;
        }

        .modal-content h3 {
            font-size: 17px;
        }

        .modal-content p {
            margin-bottom: 16px;
        }

        .modal-content code {
            background: #fbfbfc;
            padding: 2px 6px;
            border-radius: 4px;
            font-family: 'Fira Code', monospace;
            font-size: 13px;
        }

        .modal-content pre {
            background: var(--primary);
            color: var(--white);
            padding: 16px;
            border-radius: 8px;
            overflow-x: auto;
            margin-bottom: 16px;
        }

        .modal-content pre code {
            background: transparent;
            padding: 0;
        }

        .modal-content ul, .modal-content ol {
            margin-left: 24px;
            margin-bottom: 16px;
        }

        .modal-content li {
            margin-bottom: 8px;
        }

        .modal-content img {
            max-width: 100%;
            height: auto;
            display: block;
            margin: 16px 0;
            border-radius: 8px;
        }

        .modal-content figure {
            margin: 20px 0;
            text-align: center;
        }

        .modal-content figure img {
            margin: 0 auto;
        }

        .modal-content figcaption {
            font-size: 13px;
            color: var(--text-light);
            margin-top: 8px;
            font-style: italic;
        }

        .modal-content .katex-display {
            margin: 20px 0;
            overflow-x: auto;
            padding: 10px 0;
        }

        .modal-content .katex {
            font-size: 1.1em;
        }

        .loading {
            text-align: center;
            padding: 60px;
            color: var(--text-light);
        }

        .loading-spinner {
            font-size: 32px;
            animation: spin 1s linear infinite;
        }

        @keyframes spin {
            from { transform: rotate(0deg); }
            to { transform: rotate(360deg); }
        }

        .error-message {
            text-align: center;
            padding: 40px;
            color: var(--text-light);
            background: #fbfbfc;
            border-radius: 6px;
        }

        @media print {
            body {
                background: white;
                padding: 0;
                margin: 0;
            }
            .header, .nav-tabs, .header-social, .cv-download-btn {
                display: none !important;
            }
            .main-container {
                margin: 0 !important;
                padding: 0 !important;
                max-width: none !important;
            }
            .cv-container {
                box-shadow: none !important;
                border-radius: 0 !important;
                border: none !important;
                margin: 0 !important;
                width: 100% !important;
            }
            .sidebar {
                -webkit-print-color-adjust: exact !important;
                print-color-adjust: exact !important;
                background: #18181b !important;
            }
            .profile-photo {
                -webkit-print-color-adjust: exact !important;
                print-color-adjust: exact !important;
                background: #ffffff !important; color: #18181b !important;
            }
        }

        @media (max-width: 768px) {
            .header-content {
                flex-direction: column;
                gap: 12px;
                padding-top: 12px;
                padding-bottom: 12px;
            }

            .header-brand {
                padding: 0;
            }

            .nav-tabs {
                width: 100%;
                justify-content: center;
            }

            .nav-tab {
                padding: 8px 16px;
                white-space: nowrap;
            }

            .main-container {
                margin-top: 20px;
                padding: 0 12px;
            }

            .cv-container {
                flex-direction: column;
            }

            .sidebar {
                width: 100%;
                padding: 30px 25px;
            }

            .main-content {
                width: 100%;
                padding: 30px 25px;
            }

            .experience-item {
                flex-direction: row;
                gap: 16px;
            }

            .experience-logo-block {
                width: 70px;
                flex-direction: column;
            }

            .experience-date-block {
                font-size: 10px;
            }

            .experience-logo {
                width: 40px;
                height: 40px;
            }

            .academic-item {
                flex-direction: column;
                gap: 8px;
            }

            .academic-item .experience-date {
                width: 100%;
            }

            .education-item {
                flex-direction: column;
                gap: 8px;
            }

            .education-item .experience-date {
                width: 100%;
            }

            .articles-page {
                padding: 24px;
            }

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

            .modal-body {
                padding: 24px;
            }

            .modal-title {
                font-size: 22px;
            }

            .modal-image {
                height: 200px;
            }
        }