/* ===========================
   Design Tokens
   =========================== */
:root {
    --bg-deep: #0a0e1a;
    --bg-surface: #111827;
    --bg-card: rgba(255, 255, 255, 0.04);
    --bg-card-hover: rgba(255, 255, 255, 0.08);
    --glass: rgba(255, 255, 255, 0.06);
    --glass-border: rgba(255, 255, 255, 0.1);
    --glass-hover: rgba(255, 255, 255, 0.12);
    --text-primary: #f1f5f9;
    --text-secondary: #94a3b8;
    --text-muted: #64748b;
    --accent: #60a5fa;
    --accent-glow: rgba(96, 165, 250, 0.3);
    --accent-2: #a78bfa;
    --accent-3: #34d399;
    --gradient-1: linear-gradient(135deg, #60a5fa, #a78bfa);
    --gradient-2: linear-gradient(135deg, #f59e0b, #f87171);
    --gradient-3: linear-gradient(135deg, #34d399, #38bdf8);
    --cert-expert: #f87171;
    --cert-associate: #60a5fa;
    --cert-specialty: #a78bfa;
    --cert-foundation: #34d399;
    --shadow: 0 8px 32px rgba(0, 0, 0, 0.4);
    --shadow-glow: 0 0 40px rgba(96, 165, 250, 0.15);
    --radius: 16px;
    --radius-sm: 8px;
    --font-heading: 'Space Grotesk', sans-serif;
    --font-body: 'Inter', sans-serif;
    --ease: cubic-bezier(0.4, 0, 0.2, 1);
}

/* ===========================
   Reset
   =========================== */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    scroll-behavior: smooth;
    font-size: 16px;
    scroll-padding-top: 70px;
}

body {
    font-family: var(--font-body);
    background: var(--bg-deep);
    color: var(--text-primary);
    line-height: 1.7;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
}

::selection {
    background: var(--accent);
    color: var(--bg-deep);
}

/* ===========================
   Particle Canvas & Orbs
   =========================== */
#particle-canvas {
    position: fixed;
    inset: 0;
    z-index: 0;
    pointer-events: none;
}

.gradient-orb {
    position: fixed;
    border-radius: 50%;
    filter: blur(120px);
    opacity: 0.15;
    pointer-events: none;
    z-index: 0;
    animation: float 20s ease-in-out infinite;
}

.orb-1 {
    width: 600px;
    height: 600px;
    background: var(--accent);
    top: -200px;
    right: -200px;
    animation-delay: 0s;
}

.orb-2 {
    width: 500px;
    height: 500px;
    background: var(--accent-2);
    bottom: -150px;
    left: -150px;
    animation-delay: -7s;
}

.orb-3 {
    width: 400px;
    height: 400px;
    background: var(--accent-3);
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    animation-delay: -14s;
}

@keyframes float {
    0%, 100% { transform: translate(0, 0) scale(1); }
    25% { transform: translate(30px, -30px) scale(1.05); }
    50% { transform: translate(-20px, 20px) scale(0.95); }
    75% { transform: translate(10px, -10px) scale(1.02); }
}

/* ===========================
   Navigation
   =========================== */
#navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 100;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 16px 32px;
    background: rgba(10, 14, 26, 0.7);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--glass-border);
    transition: all 0.3s var(--ease);
}

#navbar.scrolled {
    padding: 10px 32px;
    background: rgba(10, 14, 26, 0.9);
}

.nav-logo {
    font-family: var(--font-heading);
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-primary);
    letter-spacing: -0.02em;
}

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

.nav-links {
    display: flex;
    gap: 8px;
}

.nav-link {
    font-family: var(--font-body);
    font-size: 0.8rem;
    font-weight: 500;
    color: var(--text-secondary);
    text-decoration: none;
    padding: 6px 14px;
    border-radius: 99px;
    transition: all 0.3s var(--ease);
    position: relative;
}

.nav-link:hover, .nav-link.active {
    color: var(--text-primary);
    background: var(--glass);
}

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

#nav-burger {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 8px;
}

#nav-burger span {
    display: block;
    width: 22px;
    height: 2px;
    background: var(--text-primary);
    transition: all 0.3s var(--ease);
    border-radius: 2px;
}

#nav-burger.open span:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
}

#nav-burger.open span:nth-child(2) {
    opacity: 0;
}

#nav-burger.open span:nth-child(3) {
    transform: rotate(-45deg) translate(5px, -5px);
}

@media (max-width: 768px) {
    #nav-burger {
        display: flex;
    }

    .nav-links {
        position: fixed;
        top: 60px;
        left: 0;
        right: 0;
        background: rgba(10, 14, 26, 0.95);
        backdrop-filter: blur(20px);
        flex-direction: column;
        padding: 24px;
        gap: 4px;
        border-bottom: 1px solid var(--glass-border);
        transform: translateY(-120%);
        transition: transform 0.4s var(--ease);
    }

    .nav-links.open {
        transform: translateY(0);
    }

    .nav-link {
        padding: 12px 16px;
        font-size: 1rem;
        border-radius: var(--radius-sm);
    }
}

/* ===========================
   Layout
   =========================== */
.container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 24px;
}

section {
    position: relative;
    z-index: 1;
    padding: 100px 0;
}

/* ===========================
   Section Header
   =========================== */
.section-header {
    margin-bottom: 48px;
}

.section-number {
    font-family: var(--font-heading);
    font-size: 0.75rem;
    font-weight: 700;
    color: var(--accent);
    letter-spacing: 0.15em;
    display: block;
    margin-bottom: 8px;
}

.section-header h2 {
    font-family: var(--font-heading);
    font-size: clamp(1.8rem, 4vw, 2.8rem);
    font-weight: 700;
    letter-spacing: -0.03em;
    line-height: 1.2;
}

.section-desc {
    color: var(--text-secondary);
    font-size: 0.9rem;
    margin-top: 8px;
}

/* ===========================
   Reveal
   =========================== */
.reveal {
    opacity: 0;
    transform: translateY(32px);
    transition: opacity 0.8s var(--ease), transform 0.8s var(--ease);
}

.reveal.visible {
    opacity: 1;
    transform: translateY(0);
}

/* ===========================
   Glass Card
   =========================== */
.glass-card {
    background: var(--glass);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    transition: all 0.4s var(--ease);
}

.glass-card:hover {
    background: var(--glass-hover);
    border-color: rgba(255, 255, 255, 0.15);
    box-shadow: var(--shadow-glow);
}

/* ===========================
   Buttons
   =========================== */
.btn {
    font-family: var(--font-body);
    font-size: 0.85rem;
    font-weight: 600;
    padding: 12px 28px;
    border-radius: 99px;
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    gap: 8px;
    transition: all 0.3s var(--ease);
    cursor: pointer;
    border: none;
}

.btn-primary {
    background: var(--gradient-1);
    color: white;
    box-shadow: 0 4px 20px var(--accent-glow);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 30px var(--accent-glow);
}

.btn-ghost {
    background: transparent;
    color: var(--text-secondary);
    border: 1px solid var(--glass-border);
}

.btn-ghost:hover {
    color: var(--text-primary);
    background: var(--glass);
}

.btn-small {
    font-size: 0.75rem;
    padding: 8px 18px;
    background: var(--glass);
    color: var(--text-secondary);
    border: 1px solid var(--glass-border);
    border-radius: 99px;
}

.btn-small:hover {
    color: var(--text-primary);
    background: var(--glass-hover);
}

/* ===========================
   Hero
   =========================== */
#hero {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding: 120px 24px 60px;
    position: relative;
}

.hero-badge {
    font-family: var(--font-body);
    font-size: 0.7rem;
    font-weight: 700;
    letter-spacing: 0.25em;
    color: var(--accent);
    background: rgba(96, 165, 250, 0.1);
    border: 1px solid rgba(96, 165, 250, 0.2);
    padding: 8px 20px;
    border-radius: 99px;
    display: inline-block;
    margin-bottom: 24px;
}

.hero-name {
    font-family: var(--font-heading);
    font-size: clamp(3rem, 8vw, 6rem);
    font-weight: 800;
    line-height: 1;
    letter-spacing: -0.04em;
    margin-bottom: 24px;
}

.hero-name .line {
    display: block;
}

.hero-name .accent {
    background: var(--gradient-1);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-tagline {
    font-size: 1.05rem;
    color: var(--text-secondary);
    max-width: 560px;
    margin: 0 auto 40px;
    line-height: 1.7;
}

.hero-stats {
    display: flex;
    gap: 48px;
    margin-bottom: 40px;
    justify-content: center;
}

.stat {
    text-align: center;
}

.stat-number {
    font-family: var(--font-heading);
    font-size: 2.5rem;
    font-weight: 800;
    color: var(--text-primary);
    display: block;
    line-height: 1;
}

.stat-label {
    font-size: 0.75rem;
    color: var(--text-muted);
    margin-top: 4px;
    display: block;
}

.hero-cta {
    display: flex;
    gap: 12px;
    margin-bottom: 40px;
    flex-wrap: wrap;
    justify-content: center;
}

.hero-location {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 0.8rem;
    color: var(--text-muted);
    flex-wrap: wrap;
    justify-content: center;
}

.hero-location svg {
    opacity: 0.6;
}

.separator {
    opacity: 0.3;
}

.scroll-indicator {
    position: absolute;
    bottom: 32px;
    left: 50%;
    transform: translateX(-50%);
    width: 24px;
    height: 40px;
    border: 2px solid var(--glass-border);
    border-radius: 12px;
    display: flex;
    justify-content: center;
    padding-top: 8px;
}

.scroll-dot {
    width: 4px;
    height: 8px;
    background: var(--accent);
    border-radius: 4px;
    animation: scrollBounce 2s ease-in-out infinite;
}

@keyframes scrollBounce {
    0%, 100% { transform: translateY(0); opacity: 1; }
    50% { transform: translateY(12px); opacity: 0.3; }
}

/* ===========================
   About
   =========================== */
.about-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 48px;
    align-items: start;
}

.about-text p {
    font-size: 0.95rem;
    color: var(--text-secondary);
    margin-bottom: 16px;
    line-height: 1.8;
}

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

.glow-text {
    color: var(--accent);
    font-weight: 600;
    position: relative;
}

.about-highlights {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 12px;
}

.highlight-card {
    background: var(--glass);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius);
    padding: 20px;
    transition: all 0.3s var(--ease);
}

.highlight-card:hover {
    background: var(--glass-hover);
    transform: translateY(-4px);
    box-shadow: var(--shadow-glow);
}

.highlight-icon {
    font-size: 1.5rem;
    margin-bottom: 8px;
}

.highlight-card h4 {
    font-family: var(--font-heading);
    font-size: 0.85rem;
    font-weight: 600;
    margin-bottom: 4px;
}

.highlight-card p {
    font-size: 0.75rem;
    color: var(--text-muted);
}

@media (max-width: 768px) {
    .about-grid {
        grid-template-columns: 1fr;
        gap: 32px;
    }
}

/* ===========================
   Career Timeline
   =========================== */
.career-timeline {
    position: relative;
}

.career-item {
    display: grid;
    grid-template-columns: 160px 40px 1fr;
    gap: 0;
    margin-bottom: 0;
    align-items: stretch;
}

.career-left {
    text-align: right;
    padding: 24px 16px 24px 0;
    display: flex;
    flex-direction: column;
    justify-content: flex-start;
    padding-top: 32px;
}

.career-period {
    font-family: var(--font-heading);
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--text-primary);
}

.career-location {
    font-size: 0.75rem;
    color: var(--text-muted);
    margin-top: 2px;
}

.career-line {
    position: relative;
    display: flex;
    justify-content: center;
}

.career-line::before {
    content: '';
    position: absolute;
    top: 0;
    bottom: 0;
    width: 2px;
    background: linear-gradient(180deg, var(--glass-border), var(--accent), var(--glass-border));
    opacity: 0.3;
}

.career-dot {
    position: relative;
    top: 36px;
    width: 14px;
    height: 14px;
    border-radius: 50%;
    background: var(--bg-deep);
    border: 2px solid var(--accent);
    z-index: 1;
    flex-shrink: 0;
}

.career-dot.active {
    background: var(--accent);
    box-shadow: 0 0 16px var(--accent-glow);
}

.career-right {
    padding: 12px 0 12px 16px;
}

.career-card {
    padding: 24px;
}

.career-tag {
    font-size: 0.65rem;
    font-weight: 700;
    letter-spacing: 0.12em;
    color: var(--accent-3);
    background: rgba(52, 211, 153, 0.1);
    border: 1px solid rgba(52, 211, 153, 0.2);
    padding: 4px 12px;
    border-radius: 99px;
    display: inline-block;
    margin-bottom: 12px;
}

.career-card h3 {
    font-family: var(--font-heading);
    font-size: 1.1rem;
    font-weight: 700;
    margin-bottom: 4px;
}

.career-company {
    font-size: 0.85rem;
    color: var(--accent);
    font-weight: 500;
    display: block;
    margin-bottom: 12px;
}

.career-card ul {
    list-style: none;
    padding: 0;
}

.career-card li {
    font-size: 0.82rem;
    color: var(--text-secondary);
    padding-left: 20px;
    position: relative;
    margin-bottom: 8px;
    line-height: 1.6;
}

.career-card li::before {
    content: '▹';
    position: absolute;
    left: 0;
    color: var(--accent);
}

@media (max-width: 768px) {
    .career-item {
        grid-template-columns: 24px 1fr;
    }

    .career-left {
        display: none;
    }

    .career-line {
        order: -1;
    }

    .career-dot {
        top: 24px;
    }

    .career-right {
        padding: 8px 0 8px 12px;
    }
}

/* ===========================
   Knowledge Graph
   =========================== */
.knowledge-wrapper {
    position: relative;
}

#knowledge-graph {
    width: 100%;
    height: 520px;
    border-radius: var(--radius);
    overflow: hidden;
}

#knowledge-graph svg {
    width: 100%;
    height: 100%;
}

.graph-legend {
    display: flex;
    gap: 16px;
    flex-wrap: wrap;
    margin-top: 16px;
    justify-content: center;
}

.legend-item {
    display: flex;
    align-items: center;
    gap: 6px;
    font-size: 0.72rem;
    color: var(--text-muted);
}

.legend-dot {
    width: 10px;
    height: 10px;
    border-radius: 50%;
    display: inline-block;
}

#reset-zoom {
    position: absolute;
    top: 16px;
    right: 16px;
    z-index: 10;
}

.tooltip {
    position: fixed;
    z-index: 200;
    background: rgba(17, 24, 39, 0.95);
    border: 1px solid var(--glass-border);
    padding: 16px;
    border-radius: var(--radius-sm);
    font-size: 0.78rem;
    max-width: 280px;
    pointer-events: none;
    backdrop-filter: blur(12px);
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.5);
}

.tooltip.hidden {
    display: none;
}

.tooltip h4 {
    font-family: var(--font-heading);
    font-size: 0.85rem;
    color: var(--accent);
    margin-bottom: 8px;
}

.tooltip ul {
    list-style: none;
    padding: 0;
}

.tooltip li {
    color: var(--text-secondary);
    padding-left: 14px;
    position: relative;
    margin-bottom: 3px;
    line-height: 1.5;
}

.tooltip li::before {
    content: '›';
    position: absolute;
    left: 0;
    color: var(--accent);
    font-weight: 700;
}

@media (max-width: 768px) {
    #knowledge-graph {
        height: 400px;
    }
}

/* ===========================
   Skills
   =========================== */
#skills-container {
    display: flex;
    flex-direction: column;
    gap: 24px;
}

.skill-category {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.skill-cat-label {
    font-family: var(--font-heading);
    font-size: 0.7rem;
    font-weight: 700;
    letter-spacing: 0.15em;
    text-transform: uppercase;
    color: var(--text-muted);
}

.skill-bars {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.skill-chip {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 10px 18px;
    background: var(--glass);
    border: 1px solid var(--glass-border);
    border-radius: 99px;
    font-size: 0.8rem;
    font-weight: 500;
    color: var(--text-secondary);
    transition: all 0.3s var(--ease);
    cursor: default;
}

.skill-chip:hover {
    background: var(--glass-hover);
    color: var(--text-primary);
    border-color: rgba(255, 255, 255, 0.2);
    transform: translateY(-2px);
    box-shadow: var(--shadow-glow);
}

.skill-dot {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    flex-shrink: 0;
}

.skill-chip.featured {
    background: rgba(96, 165, 250, 0.1);
    border-color: rgba(96, 165, 250, 0.25);
    color: var(--accent);
}

.skill-chip.featured:hover {
    background: rgba(96, 165, 250, 0.2);
    box-shadow: 0 0 20px var(--accent-glow);
}

/* ===========================
   Certifications
   =========================== */
.certs-row {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 16px;
}

.cert-card {
    padding: 28px 20px;
    text-align: center;
    position: relative;
    overflow: hidden;
}

.cert-level-bar {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
}

.cert-card[data-level="expert"] .cert-level-bar { background: var(--gradient-2); }
.cert-card[data-level="associate"] .cert-level-bar { background: var(--gradient-1); }
.cert-card[data-level="specialty"] .cert-level-bar { background: linear-gradient(135deg, #a78bfa, #ec4899); }
.cert-card[data-level="foundation"] .cert-level-bar { background: var(--gradient-3); }

.cert-badge {
    font-size: 0.55rem;
    font-weight: 700;
    letter-spacing: 0.2em;
    padding: 3px 10px;
    border-radius: 99px;
    display: inline-block;
    margin-bottom: 16px;
}

.cert-card[data-level="expert"] .cert-badge {
    color: var(--cert-expert);
    background: rgba(248, 113, 113, 0.1);
    border: 1px solid rgba(248, 113, 113, 0.2);
}

.cert-card[data-level="associate"] .cert-badge {
    color: var(--cert-associate);
    background: rgba(96, 165, 250, 0.1);
    border: 1px solid rgba(96, 165, 250, 0.2);
}

.cert-card[data-level="specialty"] .cert-badge {
    color: var(--cert-specialty);
    background: rgba(167, 139, 250, 0.1);
    border: 1px solid rgba(167, 139, 250, 0.2);
}

.cert-card[data-level="foundation"] .cert-badge {
    color: var(--cert-foundation);
    background: rgba(52, 211, 153, 0.1);
    border: 1px solid rgba(52, 211, 153, 0.2);
}

.cert-code {
    font-family: var(--font-heading);
    font-size: 1.8rem;
    font-weight: 800;
    letter-spacing: -0.02em;
    margin-bottom: 8px;
}

.cert-title {
    font-size: 0.8rem;
    color: var(--text-secondary);
    margin-bottom: 16px;
    line-height: 1.4;
}

.cert-meta {
    display: flex;
    justify-content: center;
    gap: 12px;
    font-size: 0.7rem;
    color: var(--text-muted);
}

/* ===========================
   Education
   =========================== */
.edu-row {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 16px;
}

.edu-card {
    padding: 32px;
    position: relative;
}

.edu-degree {
    font-family: var(--font-heading);
    font-size: 2.5rem;
    font-weight: 800;
    background: var(--gradient-1);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 12px;
    line-height: 1;
}

.edu-card h3 {
    font-family: var(--font-heading);
    font-size: 1.1rem;
    font-weight: 700;
    margin-bottom: 4px;
}

.edu-field {
    color: var(--accent);
    font-size: 0.9rem;
    font-weight: 500;
    margin-bottom: 8px;
}

.edu-school {
    color: var(--text-secondary);
    font-size: 0.82rem;
    margin-bottom: 12px;
}

.edu-meta {
    font-size: 0.75rem;
    color: var(--text-muted);
}

/* ===========================
   Books
   =========================== */
.books-row {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 16px;
    max-width: 700px;
}

.book-card {
    display: flex;
    align-items: stretch;
    position: relative;
    overflow: hidden;
    min-height: 120px;
}

.book-card .book-spine {
    position: absolute;
    left: 0;
    top: 0;
    bottom: 0;
    width: 4px;
    border-radius: 4px 0 0 4px;
}

.book-content {
    padding: 24px 24px 24px 20px;
    display: flex;
    flex-direction: column;
    justify-content: center;
}

.book-title {
    font-family: var(--font-heading);
    font-size: 0.95rem;
    font-weight: 700;
    line-height: 1.4;
    margin-bottom: 8px;
}

.book-author {
    font-size: 0.78rem;
    color: var(--text-muted);
}

@media (max-width: 500px) {
    .books-row {
        grid-template-columns: 1fr;
    }
}

/* ===========================
   Footer
   =========================== */
footer {
    position: relative;
    z-index: 1;
    border-top: 1px solid var(--glass-border);
    padding: 40px 0;
}

.footer-inner {
    text-align: center;
}

.footer-logo {
    font-family: var(--font-heading);
    font-size: 1.2rem;
    font-weight: 700;
    display: block;
    margin-bottom: 8px;
}

footer p {
    font-size: 0.75rem;
    color: var(--text-muted);
}

.footer-email {
    margin-top: 4px;
}

/* ===========================
   Scrollbar
   =========================== */
::-webkit-scrollbar {
    width: 6px;
}

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

::-webkit-scrollbar-thumb {
    background: rgba(255, 255, 255, 0.1);
    border-radius: 3px;
}

::-webkit-scrollbar-thumb:hover {
    background: rgba(255, 255, 255, 0.2);
}

/* ===========================
   Responsive
   =========================== */
@media (max-width: 600px) {
    section {
        padding: 60px 0;
    }

    .hero-name {
        font-size: 2.8rem;
    }

    .hero-stats {
        gap: 24px;
    }

    .stat-number {
        font-size: 2rem;
    }

    .certs-row {
        grid-template-columns: 1fr 1fr;
    }

    .edu-row {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 400px) {
    .certs-row {
        grid-template-columns: 1fr;
    }
}