/* ============================================
   PORTFOLIO STYLES - Minimalist & Geeky
   ============================================ */

:root {
    /* Colors */
    --bg-primary: #ffffff;
    --bg-secondary: #f5f5f5;
    --bg-tertiary: #fafafa;
    --fg-primary: #1a1a1a;
    --fg-secondary: #4a4a4a;
    --fg-muted: #8a8a8a;
    
    /* Accent Colors - Minimalist */
    --accent-primary: #0066cc;
    --accent-secondary: #004499;
    
    /* Terminal Colors */
    --terminal-bg: #f9f9f9;
    --terminal-text: #0066cc;
    
    /* Spacing */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 1.5rem;
    --spacing-lg: 2rem;
    --spacing-xl: 3rem;
    --spacing-2xl: 4rem;
    
    /* Typography */
    --font-mono: 'JetBrains Mono', 'Fira Code', 'Monaco', monospace;
    --font-sans: 'JetBrains Mono', 'Fira Code', -apple-system, BlinkMacSystemFont, 'Segoe UI', monospace;
    
    /* Transitions */
    --transition-fast: 0.2s ease-out;
    --transition-normal: 0.3s ease-out;
    --transition-slow: 0.5s ease-out;
}

/* ============================================
   RESET & BASE STYLES
   ============================================ */

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-sans);
    background: var(--bg-primary);
    color: var(--fg-primary);
    line-height: 1.6;
    min-height: 100vh;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

/* ============================================
   HEADER & NAVIGATION
   ============================================ */

.header {
    position: sticky;
    top: 0;
    z-index: 1000;
    background: var(--bg-primary);
    border-bottom: 1px solid #e0e0e0;
    padding: var(--spacing-md) 0;
}

.nav {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--spacing-lg);
}

.logo {
    font-family: var(--font-mono);
    font-size: 1.25rem;
    font-weight: bold;
    display: flex;
    align-items: center;
    gap: 0.25rem;
    letter-spacing: 2px;
}

.logo .bracket {
    color: var(--accent-primary);
}

.logo .name-text {
    color: var(--fg-primary);
    font-weight: 700;
}

.nav-links {
    display: flex;
    list-style: none;
    gap: var(--spacing-lg);
    flex: 1;
}

.nav-link {
    color: var(--fg-primary);
    text-decoration: none;
    font-size: 0.95rem;
    font-weight: 500;
    position: relative;
    transition: color var(--transition-fast);
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--accent-primary);
    transition: width var(--transition-fast);
}

.nav-link:hover {
    color: var(--accent-primary);
}

.nav-link:hover::after {
    width: 100%;
}

.cv-btn {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 1rem;
    background: var(--accent-primary);
    color: white;
    text-decoration: none;
    border-radius: 6px;
    font-weight: 600;
    font-size: 0.85rem;
    transition: transform var(--transition-fast), box-shadow var(--transition-fast);
    box-shadow: 0 2px 8px rgba(0, 102, 204, 0.2);
}

.cv-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0, 102, 204, 0.3);
}

.cv-btn svg {
    width: 16px;
    height: 16px;
}

@media (max-width: 768px) {
    .nav-links {
        display: none;
    }
}

/* ============================================
   HERO SECTION
   ============================================ */

.hero {
    padding: var(--spacing-2xl) 0;
    text-align: center;
    background: transparent;
    border-bottom: 1px solid rgba(0, 212, 255, 0.05);
}

.hero-content {
    animation: fadeInUp 0.8s ease-out;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 700;
    color: var(--fg-primary);
    margin-bottom: var(--spacing-sm);
    letter-spacing: -1px;
}

.hero-subtitle {
    font-size: 1.5rem;
    color: var(--accent-primary);
    margin-bottom: var(--spacing-md);
    font-weight: 500;
}

.hero-description {
    font-size: 1.1rem;
    color: var(--fg-secondary);
    max-width: 600px;
    margin: 0 auto var(--spacing-lg);
    line-height: 1.8;
}

.hero-cta {
    display: flex;
    justify-content: center;
    gap: var(--spacing-md);
}

/* ============================================
   BUTTONS
   ============================================ */

.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.75rem 1.5rem;
    border-radius: 6px;
    text-decoration: none;
    font-weight: 600;
    font-size: 0.95rem;
    transition: all var(--transition-fast);
    cursor: pointer;
    border: none;
}

.btn-primary {
    background: var(--accent-primary);
    color: white;
    box-shadow: 0 2px 8px rgba(0, 102, 204, 0.2);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0, 102, 204, 0.3);
}

.btn svg {
    width: 18px;
    height: 18px;
}

/* ============================================
   SECTION STYLES
   ============================================ */

section {
    padding: var(--spacing-2xl) 0;
    border-bottom: 1px solid rgba(0, 212, 255, 0.05);
}

.section-title {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: var(--spacing-xl);
    color: var(--fg-primary);
    position: relative;
    display: inline-block;
}

.section-title::before {
    content: '';
    position: absolute;
    bottom: -8px;
    left: 0;
    width: 40px;
    height: 3px;
    background: var(--accent-primary);
    border-radius: 2px;
}

.subsection-title {
    font-size: 1.5rem;
    font-weight: 600;
    margin-top: var(--spacing-xl);
    margin-bottom: var(--spacing-lg);
    color: var(--fg-primary);
}

/* ============================================
   ABOUT SECTION
   ============================================ */

.about-content {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xl);
}

.profile-section {
    display: flex;
    gap: var(--spacing-xl);
    align-items: flex-start;
}

.profile-image {
    width: 180px;
    height: 180px;
    min-width: 180px;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 4px 16px rgba(0, 102, 204, 0.1);
}

.profile-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    object-position: center 20%;
}

.about-text {
    flex: 1;
}

.about-text p {
    font-size: 1rem;
    color: var(--fg-secondary);
    margin-bottom: var(--spacing-md);
    line-height: 1.8;
}

.about-text strong {
    color: var(--accent-primary);
}

.quick-stats {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-md);
}

.stat {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-md);
    background: #fafafa;
    border: 1px solid #e0e0e0;
    border-radius: 8px;
    transition: all var(--transition-normal);
}

.stat:hover {
    background: white;
    border-color: var(--accent-primary);
    transform: translateY(-4px);
}

.stat-icon {
    font-size: 1.75rem;
    color: var(--accent-primary);
}

.stat-text {
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--fg-primary);
}

@media (max-width: 768px) {
    .about-content {
        grid-template-columns: 1fr;
    }
    
    .quick-stats {
        grid-template-columns: 1fr;
    }
}

/* ============================================
   RESEARCH PAPERS SECTION
   ============================================ */

.papers-grid {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
    max-height: 800px;
    overflow-y: auto;
    padding-right: 10px;
}

.papers-grid::-webkit-scrollbar {
    width: 6px;
}

.papers-grid::-webkit-scrollbar-track {
    background: transparent;
}

.papers-grid::-webkit-scrollbar-thumb {
    background: #ddd;
    border-radius: 3px;
}

.papers-grid::-webkit-scrollbar-thumb:hover {
    background: #bbb;
}

.paper-card {
    background: #fafafa;
    border: 1px solid #e0e0e0;
    border-radius: 8px;
    padding: var(--spacing-md);
    transition: all var(--transition-normal);
    position: relative;
    overflow: visible;
}

.paper-card::before {
    display: none;
}

.paper-card:hover {
    border-color: var(--accent-primary);
    background: white;
    transform: translateY(-4px);
    box-shadow: 0 4px 12px rgba(0, 102, 204, 0.12);
}

.paper-status {
    display: inline-block;
    padding: 0.2rem 0.6rem;
    border-radius: 20px;
    font-size: 0.7rem;
    font-weight: 600;
    text-transform: uppercase;
    margin-bottom: var(--spacing-sm);
}

.paper-status.accepted {
    background: #e3f2fd;
    color: var(--accent-primary);
}

.paper-status.communicated {
    background: #f5f5f5;
    color: var(--fg-secondary);
}

.paper-title {
    font-size: 1rem;
    font-weight: 600;
    color: var(--fg-primary);
    margin-bottom: var(--spacing-sm);
    line-height: 1.45;
}

.paper-venue {
    color: var(--accent-primary);
    font-size: 0.82rem;
    font-weight: 500;
    margin-bottom: 0.2rem;
}

.paper-year {
    color: var(--fg-muted);
    font-size: 0.78rem;
    margin-bottom: var(--spacing-sm);
}

.paper-links {
    display: flex;
    gap: var(--spacing-sm);
    margin-top: var(--spacing-sm);
}

.link-btn {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    padding: 0.4rem 0.8rem;
    background: transparent;
    color: var(--accent-primary);
    text-decoration: none;
    border-radius: 4px;
    font-size: 0.85rem;
    font-weight: 500;
    transition: all var(--transition-fast);
    border: 1px solid var(--accent-primary);
}

.link-btn:hover {
    background: var(--accent-primary);
    color: white;
    transform: translateY(-1px);
}

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

/* ============================================
   TERMINAL SECTION
   ============================================ */

.terminal {
    background: var(--terminal-bg);
    border: 1px solid #ddd;
    border-radius: 8px;
    overflow: hidden;
    font-family: var(--font-mono);
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
}

.terminal-header {
    background: #f0f0f0;
    padding: var(--spacing-sm) var(--spacing-md);
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    border-bottom: 1px solid #ddd;
}

.terminal-buttons {
    display: flex;
    gap: 0.5rem;
}

.terminal-btn {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    cursor: pointer;
    transition: opacity var(--transition-fast);
}

.terminal-btn.red {
    background: #ff5555;
}

.terminal-btn.yellow {
    background: #ffbb33;
}

.terminal-btn.green {
    background: #44dd44;
}

.terminal-title {
    color: var(--fg-secondary);
    font-size: 0.85rem;
    flex: 1;
    text-align: center;
}

.terminal-content {
    padding: var(--spacing-lg);
    max-height: 400px;
    overflow-y: auto;
    overflow-x: hidden;
}

.terminal-content::-webkit-scrollbar {
    width: 6px;
}

.terminal-content::-webkit-scrollbar-track {
    background: #f0f0f0;
}

.terminal-content::-webkit-scrollbar-thumb {
    background: #bbb;
    border-radius: 3px;
}

.terminal-content::-webkit-scrollbar-thumb:hover {
    background: #999;
}

.terminal-line {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--fg-primary);
    margin-bottom: 0.5rem;
    line-height: 1.5;
}

.prompt {
    color: var(--accent-primary);
    font-weight: bold;
}

.command {
    color: var(--fg-primary);
}

.blinking-cursor {
    animation: blink 1s infinite;
}

@keyframes blink {
    0%, 50% {
        opacity: 1;
    }
    51%, 100% {
        opacity: 0;
    }
}

.terminal-output {
    margin-top: var(--spacing-md);
}

.news-item {
    display: grid;
    grid-template-columns: 68px 1fr;
    gap: var(--spacing-md);
    padding: var(--spacing-md) 0;
    border-left: 2px solid #ddd;
    padding-left: var(--spacing-md);
    transition: all var(--transition-fast);
}

.news-item:hover {
    border-left-color: var(--accent-primary);
    padding-left: calc(var(--spacing-md) + 4px);
}

.news-date {
    color: var(--accent-primary);
    font-weight: 600;
    font-size: 0.85rem;
}

.news-text {
    color: var(--fg-secondary);
    font-size: 0.95rem;
    line-height: 1.5;
}

/* ============================================
   EDUCATION SECTION - HORIZONTAL PROGRESSION
   ============================================ */

.education-progression {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
    gap: var(--spacing-md);
    padding: var(--spacing-md) 0;
    margin-bottom: var(--spacing-2xl);
}

.education-progression::-webkit-scrollbar {
    height: 6px;
}

.education-progression::-webkit-scrollbar-track {
    background: transparent;
}

.education-progression::-webkit-scrollbar-thumb {
    background: #ddd;
    border-radius: 3px;
}

.education-progression::-webkit-scrollbar-thumb:hover {
    background: #bbb;
}

.edu-card {
    min-width: auto;
    flex-shrink: auto;
    background: #fafafa;
    border: 1px solid #e0e0e0;
    border-radius: 8px;
    padding: var(--spacing-md);
    text-align: center;
    transition: all var(--transition-normal);
}

.edu-card:hover {
    background: white;
    border-color: var(--accent-primary);
    transform: translateY(-4px);
    box-shadow: 0 4px 12px rgba(0, 102, 204, 0.12);
}

.edu-card.current {
    background: linear-gradient(135deg, #e8eef7, #f5f9ff);
    border-color: var(--accent-primary);
}

.edu-year {
    font-weight: 700;
    color: var(--accent-primary);
    font-size: 0.95rem;
    margin-bottom: 0.2rem;
}

.edu-level {
    font-weight: 600;
    color: var(--fg-primary);
    font-size: 0.8rem;
    margin-bottom: 0.35rem;
}

.edu-school {
    font-size: 0.75rem;
    color: var(--fg-secondary);
    margin-bottom: 0.2rem;
}

.edu-location {
    font-size: 0.65rem;
    color: var(--fg-muted);
}

.edu-arrow {
    display: none;
}

/* ============================================
   ACHIEVEMENTS GRID
   ============================================ */

.achievements-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--spacing-lg);
    margin-top: var(--spacing-lg);
    max-height: 600px;
    overflow-y: auto;
    padding-right: 8px;
}

.achievement {
    background: #fafafa;
    border: 1px solid #e0e0e0;
    border-radius: 8px;
    padding: var(--spacing-lg);
    text-align: center;
    transition: all var(--transition-normal);
}

.achievement:hover {
    background: white;
    border-color: var(--accent-primary);
    transform: translateY(-4px);
}

.achievement-icon {
    font-size: 1.75rem;
    margin-bottom: var(--spacing-sm);
    display: block;
    color: var(--accent-primary);
}

.achievement p {
    color: var(--fg-secondary);
    line-height: 1.6;
}

.achievement strong {
    color: var(--fg-primary);
}

@media (max-width: 768px) {
    .timeline::before {
        left: 12px;
    }
    
    .timeline-item {
        grid-template-columns: 44px 1fr;
    }
    
    .timeline-marker {
        width: 32px;
        height: 32px;
        font-size: 0.7rem;
    }
}

/* ============================================
   CONTACT SECTION
   ============================================ */

.contact-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--spacing-xl);
    margin-bottom: var(--spacing-2xl);
}

.contact-group {
    background: #fafafa;
    border: 1px solid #e0e0e0;
    border-radius: 8px;
    padding: var(--spacing-lg);
    transition: all var(--transition-normal);
}

.contact-group:hover {
    background: white;
    border-color: var(--accent-primary);
    transform: translateY(-4px);
}

.contact-group-title {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 1rem;
    font-weight: 600;
    color: var(--fg-primary);
    margin-bottom: var(--spacing-md);
}

.contact-group-title i {
    color: var(--accent-primary);
}

.contact-items {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

.contact-link {
    color: var(--accent-primary);
    text-decoration: none;
    font-weight: 500;
    transition: all var(--transition-fast);
    display: inline-flex;
    align-items: center;
    fit-content: true;
}

.contact-link:hover {
    color: var(--fg-primary);
}

.social-links {
    display: flex;
    gap: var(--spacing-md);
    flex-wrap: wrap;
}

.social-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 44px;
    height: 44px;
    border-radius: 8px;
    background: rgba(0, 212, 255, 0.1);
    color: var(--accent-primary);
    transition: all var(--transition-fast);
    border: 1px solid rgba(0, 212, 255, 0.2);
    text-decoration: none;
}

.social-btn:hover {
    background: var(--accent-primary);
    color: var(--bg-primary);
    transform: translateY(-2px);
    border-color: transparent;
}

.social-btn i {
    font-size: 1.2rem;
}

/* ============================================
   CV SECTION
   ============================================ */

.cv-section {
    text-align: center;
    background: #fafafa;
    border: 1px solid #e0e0e0;
    border-radius: 8px;
    padding: var(--spacing-xl);
}

.cv-section h3 {
    color: var(--fg-primary);
    margin-bottom: var(--spacing-md);
    font-size: 1.2rem;
}

.cv-download-btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.75rem 1.5rem;
    background: var(--accent-primary);
    color: white;
    text-decoration: none;
    border-radius: 6px;
    font-weight: 600;
    font-size: 0.95rem;
    transition: all var(--transition-fast);
    box-shadow: 0 2px 8px rgba(0, 102, 204, 0.2);
}

.cv-download-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0, 102, 204, 0.3);
}

.cv-download-btn i {
    font-size: 1rem;
}

/* ============================================
   FOOTER
   ============================================ */

.footer {
    background: var(--bg-secondary);
    border-top: 1px solid #e0e0e0;
    padding: var(--spacing-lg) 0;
    text-align: center;
}

.footer p {
    color: var(--fg-muted);
    font-family: var(--font-mono);
    font-size: 0.85rem;
}

/* ============================================
   ANIMATIONS
   ============================================ */

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes fadeIn {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

/* ============================================
   SCROLLBAR
   ============================================ */

::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: var(--bg-secondary);
}

::-webkit-scrollbar-thumb {
    background: var(--accent-primary);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--accent-secondary);
}

/* ============================================
   RESPONSIVE DESIGN
   ============================================ */

@media (max-width: 768px) {
    :root {
        --spacing-xl: 2rem;
        --spacing-2xl: 2.5rem;
    }
    
    .profile-section {
        flex-direction: column;
        align-items: center;
        text-align: center;
    }

    .profile-image {
        width: 140px;
        height: 140px;
        margin: 0 auto;
    }
    
    .hero-title {
        font-size: 2.5rem;
    }
    
    .hero-subtitle {
        font-size: 1.1rem;
    }
    
    .section-title {
        font-size: 1.5rem;
    }
    
    .nav-links {
        gap: var(--spacing-md);
    }
    
    .papers-grid {
        max-height: 600px;
    }
    
    .contact-grid {
        grid-template-columns: 1fr;
    }
    
    .terminal-content {
        min-height: 250px;
        font-size: 0.85rem;
    }
    
    .news-item {
        grid-template-columns: 64px 1fr;
        gap: var(--spacing-sm);
        padding: var(--spacing-md) 0;
    }
    
    .hero-cta {
        flex-direction: column;
        align-items: center;
    }

    .education-progression {
        grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
        gap: var(--spacing-sm);
    }

    .edu-card {
        min-width: auto;
        padding: var(--spacing-sm);
    }

    .edu-year {
        font-size: 0.9rem;
    }

    .edu-level {
        font-size: 0.75rem;
    }

    .edu-school {
        font-size: 0.7rem;
    }

    .edu-location {
        font-size: 0.6rem;
    }
}

@media (max-width: 480px) {
    :root {
        --spacing-md: 1rem;
        --spacing-lg: 1.5rem;
        --spacing-xl: 1.5rem;
        --spacing-2xl: 2rem;
    }
    
    .profile-section {
        flex-direction: column;
        align-items: center;
        text-align: center;
    }

    .profile-image {
        width: 120px;
        height: 120px;
        margin-bottom: var(--spacing-md);
    }
    
    body {
        padding: var(--spacing-md);
    }
    
    .section {
        padding: var(--spacing-lg) var(--spacing-md);
    }
    
    .hero-title {
        font-size: 1.75rem;
    }
    
    .hero-subtitle {
        font-size: 1rem;
    }
    
    .section-title {
        font-size: 1.3rem;
    }
    
    .logo {
        font-size: 1rem;
    }
    
    .cv-btn {
        padding: 0.4rem 0.8rem;
        font-size: 0.75rem;
    }
    
    .papers-grid {
        max-height: 400px;
    }

    .contact-grid {
        grid-template-columns: 1fr;
    }
    
    .terminal-content {
        padding: var(--spacing-md);
        font-size: 0.75rem;
    }
    
    .news-date {
        font-size: 0.75rem;
    }

    .education-progression {
        grid-template-columns: repeat(2, 1fr);
        gap: var(--spacing-sm);
        padding: 0;
    }

    .edu-card {
        min-width: auto;
        padding: var(--spacing-xs);
    }

    .edu-year {
        font-size: 0.8rem;
        font-weight: bold;
    }

    .edu-level {
        font-size: 0.7rem;
    }

    .edu-school {
        font-size: 0.6rem;
    }

    .edu-location {
        font-size: 0.55rem;
    }
}