/* ===== CSS Variables & Root ===== */
:root {
    --primary: #6C63FF;
    --primary-dark: #5A52D5;
    --secondary: #FF6584;
    --accent: #00D2AF;
    --accent-blue: #1DA1F2;
    --gradient-1: linear-gradient(135deg, #6C63FF 0%, #4ECDC4 50%, #00D2AF 100%);
    --gradient-2: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --gradient-3: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
    --gradient-4: linear-gradient(135deg, #4facfe 0%, #00f2fe 100%);
    --gradient-hero: linear-gradient(135deg, #0c0c1d 0%, #1a1a3e 25%, #16213e 50%, #0f3460 75%, #1a1a3e 100%);
    --bg-dark: #0c0c1d;
    --bg-card: #151530;
    --bg-card-hover: #1e1e4a;
    --text-primary: #ffffff;
    --text-secondary: #a0a0c0;
    --text-muted: #6a6a8a;
    --border-color: rgba(108, 99, 255, 0.2);
    --shadow-sm: 0 2px 10px rgba(0, 0, 0, 0.2);
    --shadow-md: 0 8px 30px rgba(0, 0, 0, 0.3);
    --shadow-lg: 0 20px 60px rgba(0, 0, 0, 0.4);
    --shadow-glow: 0 0 40px rgba(108, 99, 255, 0.15);
    --radius-sm: 8px;
    --radius-md: 16px;
    --radius-lg: 24px;
    --radius-full: 50%;
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --font-main: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    --font-heading: 'Space Grotesk', 'Inter', sans-serif;
}

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

html {
    scroll-behavior: smooth;
    scroll-padding-top: 80px;
}

body {
    font-family: var(--font-main);
    background-color: var(--bg-dark);
    color: var(--text-primary);
    line-height: 1.7;
    overflow-x: hidden;
}

a {
    text-decoration: none;
    color: inherit;
}

img {
    max-width: 100%;
    height: auto;
    display: block;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

/* ===== Scrollbar ===== */
::-webkit-scrollbar {
    width: 8px;
}

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

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

::-webkit-scrollbar-thumb:hover {
    background: var(--primary-dark);
}

/* ===== Selection ===== */
::selection {
    background: var(--primary);
    color: white;
}

/* ===== Navigation ===== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    padding: 16px 0;
    transition: var(--transition);
}

.navbar.scrolled {
    background: rgba(12, 12, 29, 0.9);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    padding: 10px 0;
    box-shadow: 0 4px 30px rgba(0, 0, 0, 0.3);
    border-bottom: 1px solid var(--border-color);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.nav-logo {
    font-family: var(--font-heading);
    font-size: 1.5rem;
    font-weight: 700;
    background: var(--gradient-1);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    letter-spacing: -1px;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 8px;
}

.nav-link {
    padding: 8px 16px;
    border-radius: var(--radius-sm);
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--text-secondary);
    transition: var(--transition);
    position: relative;
}

.nav-link:hover,
.nav-link.active {
    color: var(--text-primary);
    background: rgba(108, 99, 255, 0.1);
}

.nav-link.active::after {
    content: '';
    position: absolute;
    bottom: 2px;
    left: 50%;
    transform: translateX(-50%);
    width: 20px;
    height: 2px;
    background: var(--primary);
    border-radius: 2px;
}

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 5px;
}

.nav-toggle span {
    width: 25px;
    height: 2px;
    background: var(--text-primary);
    border-radius: 2px;
    transition: var(--transition);
}

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

.nav-toggle.active span:nth-child(2) {
    opacity: 0;
}

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

/* ===== Hero Section ===== */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    position: relative;
    background: var(--gradient-hero);
    overflow: hidden;
}

.hero-bg {
    position: absolute;
    inset: 0;
    overflow: hidden;
}

.floating-shapes .shape {
    position: absolute;
    border-radius: 50%;
    opacity: 0.08;
    animation: float 20s infinite ease-in-out;
}

.shape-1 {
    width: 600px;
    height: 600px;
    background: var(--primary);
    top: -200px;
    right: -100px;
    animation-delay: 0s;
}

.shape-2 {
    width: 400px;
    height: 400px;
    background: var(--accent);
    bottom: -100px;
    left: -100px;
    animation-delay: -5s;
}

.shape-3 {
    width: 300px;
    height: 300px;
    background: var(--secondary);
    top: 50%;
    left: 50%;
    animation-delay: -10s;
}

.shape-4 {
    width: 200px;
    height: 200px;
    background: var(--accent-blue);
    top: 20%;
    left: 10%;
    animation-delay: -15s;
}

.shape-5 {
    width: 350px;
    height: 350px;
    background: #f093fb;
    bottom: 20%;
    right: 20%;
    animation-delay: -7s;
}

@keyframes float {
    0%, 100% { transform: translate(0, 0) rotate(0deg); }
    25% { transform: translate(30px, -30px) rotate(5deg); }
    50% { transform: translate(-20px, 20px) rotate(-5deg); }
    75% { transform: translate(20px, 10px) rotate(3deg); }
}

.hero-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
    position: relative;
    z-index: 1;
    padding-top: 80px;
}

.hero-greeting {
    font-size: 1.1rem;
    color: var(--accent);
    font-weight: 500;
    margin-bottom: 8px;
    letter-spacing: 2px;
    text-transform: uppercase;
}

.hero-name {
    font-family: var(--font-heading);
    font-size: clamp(2.5rem, 6vw, 4.5rem);
    font-weight: 800;
    line-height: 1.1;
    margin-bottom: 8px;
    background: var(--gradient-1);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-title {
    font-family: var(--font-heading);
    font-size: clamp(1.5rem, 3vw, 2.5rem);
    font-weight: 600;
    color: var(--text-secondary);
    margin-bottom: 16px;
}

.hero-subtitle {
    font-size: 1.15rem;
    color: var(--text-secondary);
    margin-bottom: 32px;
    min-height: 1.6rem;
}

.cursor {
    color: var(--accent);
    animation: blink 1s infinite;
}

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

.hero-buttons {
    display: flex;
    gap: 16px;
    margin-bottom: 40px;
    flex-wrap: wrap;
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 14px 32px;
    border-radius: var(--radius-sm);
    font-size: 0.95rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    border: none;
    font-family: var(--font-main);
}

.btn-primary {
    background: var(--gradient-1);
    color: white;
    box-shadow: 0 4px 20px rgba(108, 99, 255, 0.3);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 30px rgba(108, 99, 255, 0.5);
}

.btn-secondary {
    background: transparent;
    color: var(--text-primary);
    border: 2px solid var(--border-color);
}

.btn-secondary:hover {
    border-color: var(--primary);
    background: rgba(108, 99, 255, 0.1);
    transform: translateY(-2px);
}

.hero-social {
    display: flex;
    gap: 12px;
}

.social-link {
    width: 44px;
    height: 44px;
    border-radius: var(--radius-full);
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--border-color);
    color: var(--text-secondary);
    font-size: 1.1rem;
    transition: var(--transition);
}

.social-link:hover {
    background: var(--primary);
    color: white;
    border-color: var(--primary);
    transform: translateY(-3px);
    box-shadow: 0 8px 20px rgba(108, 99, 255, 0.3);
}

/* Hero Image */
.hero-image {
    display: flex;
    justify-content: center;
    align-items: center;
}

.profile-container {
    position: relative;
    width: 320px;
    height: 320px;
}

.profile-img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    border-radius: var(--radius-full);
    border: 4px solid transparent;
    background-clip: padding-box;
    position: relative;
    z-index: 1;
}

.profile-ring {
    position: absolute;
    inset: -8px;
    border-radius: var(--radius-full);
    background: var(--gradient-1);
    z-index: 0;
    animation: spin 8s linear infinite;
}

.profile-ring::before {
    content: '';
    position: absolute;
    inset: 4px;
    border-radius: var(--radius-full);
    background: var(--bg-dark);
}

.profile-dots {
    position: absolute;
    inset: -25px;
    border-radius: var(--radius-full);
    border: 2px dashed rgba(108, 99, 255, 0.3);
    animation: spin 20s linear infinite reverse;
}

@keyframes spin {
    100% { transform: rotate(360deg); }
}

/* Scroll Indicator */
.scroll-indicator {
    position: absolute;
    bottom: 30px;
    left: 50%;
    transform: translateX(-50%);
    text-align: center;
    z-index: 1;
}

.scroll-indicator a {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 8px;
    color: var(--text-muted);
    font-size: 0.8rem;
    letter-spacing: 1px;
    text-transform: uppercase;
}

.mouse {
    width: 24px;
    height: 38px;
    border: 2px solid var(--text-muted);
    border-radius: 12px;
    position: relative;
}

.wheel {
    width: 3px;
    height: 8px;
    background: var(--accent);
    border-radius: 2px;
    position: absolute;
    top: 6px;
    left: 50%;
    transform: translateX(-50%);
    animation: scroll-wheel 1.5s infinite;
}

@keyframes scroll-wheel {
    0% { opacity: 1; transform: translateX(-50%) translateY(0); }
    100% { opacity: 0; transform: translateX(-50%) translateY(12px); }
}

/* ===== Section Styles ===== */
.section {
    padding: 100px 0;
    position: relative;
}

.section-header {
    text-align: center;
    margin-bottom: 60px;
}

.section-tag {
    display: inline-block;
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--accent);
    text-transform: uppercase;
    letter-spacing: 3px;
    margin-bottom: 12px;
    padding: 6px 16px;
    background: rgba(0, 210, 175, 0.1);
    border-radius: 20px;
    border: 1px solid rgba(0, 210, 175, 0.2);
}

.section-title {
    font-family: var(--font-heading);
    font-size: clamp(1.8rem, 4vw, 2.8rem);
    font-weight: 700;
    background: var(--gradient-1);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

/* ===== About Section ===== */
.about {
    background: linear-gradient(180deg, var(--bg-dark) 0%, #0e0e28 100%);
}

.about-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
    margin-bottom: 60px;
}

.about-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 32px;
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}

.about-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: var(--gradient-1);
    opacity: 0;
    transition: var(--transition);
}

.about-card:hover {
    transform: translateY(-5px);
    border-color: rgba(108, 99, 255, 0.4);
    box-shadow: var(--shadow-glow);
}

.about-card:hover::before {
    opacity: 1;
}

.about-card.main-about {
    grid-column: span 2;
}

.about-icon {
    width: 50px;
    height: 50px;
    border-radius: var(--radius-sm);
    background: rgba(108, 99, 255, 0.1);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.3rem;
    color: var(--primary);
    margin-bottom: 20px;
}

.about-card h3 {
    font-family: var(--font-heading);
    font-size: 1.2rem;
    margin-bottom: 12px;
    color: var(--text-primary);
}

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

.tech-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    margin-top: 8px;
}

.tag {
    padding: 6px 14px;
    background: rgba(108, 99, 255, 0.1);
    border: 1px solid rgba(108, 99, 255, 0.2);
    border-radius: 20px;
    font-size: 0.85rem;
    color: var(--primary);
    font-weight: 500;
    transition: var(--transition);
}

.tag:hover {
    background: var(--primary);
    color: white;
}

/* Stats */
.about-stats {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
}

.stat-item {
    text-align: center;
    padding: 32px 20px;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    transition: var(--transition);
}

.stat-item:hover {
    transform: translateY(-5px);
    border-color: rgba(108, 99, 255, 0.4);
    box-shadow: var(--shadow-glow);
}

.stat-number {
    font-family: var(--font-heading);
    font-size: 2.5rem;
    font-weight: 700;
    background: var(--gradient-1);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 4px;
}

.stat-label {
    font-size: 0.9rem;
    color: var(--text-secondary);
    font-weight: 500;
}

/* ===== Education Timeline ===== */
.education {
    background: linear-gradient(180deg, #0e0e28 0%, var(--bg-dark) 100%);
}

.timeline {
    position: relative;
    max-width: 800px;
    margin: 0 auto;
}

.timeline::before {
    content: '';
    position: absolute;
    left: 20px;
    top: 0;
    bottom: 0;
    width: 2px;
    background: linear-gradient(180deg, var(--primary) 0%, var(--accent) 100%);
}

.timeline-item {
    position: relative;
    padding-left: 60px;
    margin-bottom: 40px;
}

.timeline-item:last-child {
    margin-bottom: 0;
}

.timeline-dot {
    position: absolute;
    left: 12px;
    top: 8px;
    width: 18px;
    height: 18px;
    border-radius: var(--radius-full);
    background: var(--primary);
    border: 3px solid var(--bg-dark);
    z-index: 1;
    box-shadow: 0 0 0 3px rgba(108, 99, 255, 0.3);
}

.timeline-content {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 28px;
    transition: var(--transition);
    position: relative;
}

.timeline-content:hover {
    border-color: rgba(108, 99, 255, 0.4);
    box-shadow: var(--shadow-glow);
    transform: translateX(5px);
}

.timeline-date {
    display: inline-block;
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--accent);
    background: rgba(0, 210, 175, 0.1);
    padding: 4px 12px;
    border-radius: 12px;
    margin-bottom: 12px;
}

.timeline-content h3 {
    font-family: var(--font-heading);
    font-size: 1.15rem;
    margin-bottom: 4px;
    color: var(--text-primary);
}

.timeline-content h4 {
    font-size: 0.95rem;
    color: var(--primary);
    font-weight: 500;
    margin-bottom: 8px;
}

.timeline-content p {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.highlight-badge {
    display: inline-block;
    margin-top: 8px;
    padding: 4px 12px;
    background: linear-gradient(135deg, #FFD700, #FFA500);
    color: #1a1a1a;
    font-size: 0.8rem;
    font-weight: 600;
    border-radius: 12px;
}

/* ===== Research / Positions ===== */
.research {
    background: linear-gradient(180deg, var(--bg-dark) 0%, #0e0e28 100%);
}

.position-cards {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
    gap: 24px;
    margin-bottom: 20px;
}

.position-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 28px;
    transition: var(--transition);
    position: relative;
}

.position-card:hover {
    transform: translateY(-5px);
    border-color: rgba(108, 99, 255, 0.4);
    box-shadow: var(--shadow-glow);
}

.position-card.current {
    border-color: rgba(0, 210, 175, 0.3);
}

.position-badge {
    position: absolute;
    top: 16px;
    right: 16px;
    padding: 4px 12px;
    background: rgba(0, 210, 175, 0.15);
    color: var(--accent);
    font-size: 0.75rem;
    font-weight: 600;
    border-radius: 12px;
    text-transform: uppercase;
    letter-spacing: 1px;
}

.position-badge.military {
    background: rgba(255, 101, 132, 0.15);
    color: var(--secondary);
}

.position-card h3 {
    font-family: var(--font-heading);
    font-size: 1.1rem;
    margin-bottom: 4px;
    color: var(--text-primary);
    padding-right: 70px;
}

.position-card h4 {
    font-size: 0.95rem;
    color: var(--primary);
    font-weight: 500;
    margin-bottom: 4px;
}

.position-dept {
    font-size: 0.85rem;
    color: var(--text-muted);
    margin-bottom: 8px;
}

.position-card p {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.position-date {
    display: inline-block;
    margin-top: 12px;
    font-size: 0.8rem;
    font-weight: 600;
    color: var(--accent-blue);
    background: rgba(29, 161, 242, 0.1);
    padding: 4px 12px;
    border-radius: 12px;
}

/* Skills */
.skills-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
    gap: 24px;
    margin-bottom: 60px;
}

.skill-category {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 28px;
}

.skill-category h3 {
    font-family: var(--font-heading);
    font-size: 1.1rem;
    margin-bottom: 20px;
    color: var(--text-primary);
    display: flex;
    align-items: center;
    gap: 10px;
}

.skill-category h3 i {
    color: var(--primary);
}

.skill-bar {
    margin-bottom: 16px;
}

.skill-bar:last-child {
    margin-bottom: 0;
}

.skill-info {
    display: flex;
    justify-content: space-between;
    margin-bottom: 6px;
    font-size: 0.9rem;
}

.skill-info span:first-child {
    color: var(--text-secondary);
}

.skill-info span:last-child {
    color: var(--accent);
    font-weight: 600;
}

.skill-progress {
    height: 8px;
    background: rgba(255, 255, 255, 0.05);
    border-radius: 4px;
    overflow: hidden;
}

.skill-fill {
    height: 100%;
    background: var(--gradient-1);
    border-radius: 4px;
    width: 0;
    transition: width 1.5s cubic-bezier(0.4, 0, 0.2, 1);
}

/* GitHub Repos */
.github-repos {
    margin-top: 20px;
}

.github-repos h3 {
    font-family: var(--font-heading);
    font-size: 1.3rem;
    margin-bottom: 24px;
    color: var(--text-primary);
    display: flex;
    align-items: center;
    gap: 10px;
}

.github-repos h3 i {
    color: var(--text-primary);
}

.repo-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
    gap: 20px;
}

.repo-card {
    display: flex;
    flex-direction: column;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    transition: var(--transition);
}

.repo-card:hover {
    transform: translateY(-5px);
    border-color: rgba(108, 99, 255, 0.4);
    box-shadow: var(--shadow-glow);
}

.repo-card-link {
    display: flex;
    flex-direction: column;
    flex: 1;
    padding: 24px;
    padding-bottom: 0;
}

.repo-card-link:hover {
    text-decoration: none;
}

.repo-card.featured {
    border-color: rgba(255, 215, 0, 0.4);
    background: linear-gradient(135deg, var(--bg-card) 0%, rgba(255, 215, 0, 0.05) 100%);
}

.repo-card.featured:hover {
    border-color: rgba(255, 215, 0, 0.6);
    box-shadow: 0 0 40px rgba(255, 215, 0, 0.15);
}

.featured-badge {
    display: inline-block;
    padding: 3px 10px;
    background: linear-gradient(135deg, #FFD700, #FFA500);
    color: #1a1a1a;
    font-size: 0.7rem;
    font-weight: 700;
    border-radius: 10px;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin-left: auto;
}

.repo-header {
    display: flex;
    align-items: center;
    gap: 10px;
    margin-bottom: 12px;
}

.repo-header i {
    color: var(--primary);
    font-size: 1.1rem;
}

.repo-header span {
    font-family: var(--font-heading);
    font-weight: 600;
    font-size: 1rem;
}

.repo-card p {
    color: var(--text-secondary);
    font-size: 0.9rem;
    flex: 1;
    margin-bottom: 16px;
}

.repo-footer {
    display: flex;
    justify-content: space-between;
    align-items: center;
    color: var(--text-muted);
    font-size: 0.85rem;
    padding: 12px 24px;
    border-top: 1px solid var(--border-color);
    margin-top: auto;
}

.repo-footer span:first-child {
    display: flex;
    align-items: center;
    gap: 6px;
}

.repo-footer .fa-star {
    color: #FFD700;
}

.repo-paper-link {
    color: var(--text-muted);
    transition: var(--transition);
    display: flex;
    align-items: center;
    justify-content: center;
    width: 32px;
    height: 32px;
    border-radius: var(--radius-full);
    background: rgba(108, 99, 255, 0.1);
}

.repo-paper-link:hover {
    color: white;
    background: var(--primary);
}

.repo-paper-link .fa-arrow-right {
    transition: var(--transition);
}

.repo-card:hover .repo-paper-link .fa-arrow-right {
    transform: translateX(3px);
}

/* ===== Publications ===== */
.publications {
    background: linear-gradient(180deg, #0e0e28 0%, var(--bg-dark) 100%);
}

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

.filter-btn {
    padding: 8px 20px;
    background: transparent;
    border: 1px solid var(--border-color);
    border-radius: 20px;
    color: var(--text-secondary);
    font-size: 0.9rem;
    font-weight: 500;
    cursor: pointer;
    transition: var(--transition);
    font-family: var(--font-main);
}

.filter-btn:hover,
.filter-btn.active {
    background: var(--primary);
    color: white;
    border-color: var(--primary);
}

.publications-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
    gap: 24px;
}

.pub-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 28px;
    transition: var(--transition);
}

.pub-card:hover {
    transform: translateY(-5px);
    border-color: rgba(108, 99, 255, 0.4);
    box-shadow: var(--shadow-glow);
}

.pub-card.hidden {
    display: none;
}

.pub-type {
    display: inline-block;
    padding: 4px 12px;
    font-size: 0.75rem;
    font-weight: 600;
    border-radius: 12px;
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-bottom: 12px;
}

.pub-type.journal {
    background: rgba(108, 99, 255, 0.15);
    color: var(--primary);
}

.pub-type.preprint {
    background: rgba(255, 101, 132, 0.15);
    color: var(--secondary);
}

.pub-type.submitted {
    background: rgba(0, 210, 175, 0.15);
    color: var(--accent);
}

.pub-card h3 {
    font-family: var(--font-heading);
    font-size: 1rem;
    margin-bottom: 8px;
    color: var(--text-primary);
    line-height: 1.4;
}

.pub-authors {
    font-size: 0.9rem;
    color: var(--text-secondary);
    margin-bottom: 4px;
}

.pub-journal {
    font-size: 0.85rem;
    color: var(--text-muted);
    font-style: italic;
    margin-bottom: 12px;
}

.pub-link {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--primary);
    transition: var(--transition);
}

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

.pub-link i {
    font-size: 0.8rem;
    transition: var(--transition);
}

.pub-link:hover i {
    transform: translateX(3px);
}

.pub-more {
    text-align: center;
    margin-top: 40px;
}

/* ===== Contact ===== */
.contact {
    background: linear-gradient(180deg, var(--bg-dark) 0%, #0e0e28 100%);
}

.contact-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 40px;
}

.contact-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 28px;
    margin-bottom: 20px;
    transition: var(--transition);
}

.contact-card:hover {
    border-color: rgba(108, 99, 255, 0.4);
    box-shadow: var(--shadow-glow);
}

.contact-icon {
    width: 48px;
    height: 48px;
    border-radius: var(--radius-sm);
    background: rgba(108, 99, 255, 0.1);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.2rem;
    color: var(--primary);
    margin-bottom: 16px;
}

.contact-card h3 {
    font-family: var(--font-heading);
    font-size: 1rem;
    margin-bottom: 8px;
    color: var(--text-primary);
}

.contact-card p {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.contact-card a {
    color: var(--primary);
    transition: var(--transition);
}

.contact-card a:hover {
    color: var(--accent);
}

.contact-links h3 {
    font-family: var(--font-heading);
    font-size: 1.2rem;
    margin-bottom: 20px;
    color: var(--text-primary);
}

.contact-social-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 16px;
}

.contact-social-card {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 16px 20px;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    transition: var(--transition);
}

.contact-social-card:hover {
    transform: translateY(-3px);
    border-color: rgba(108, 99, 255, 0.4);
    box-shadow: var(--shadow-glow);
}

.contact-social-card i {
    font-size: 1.3rem;
    color: var(--primary);
    width: 24px;
    text-align: center;
}

.contact-social-card span {
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--text-secondary);
}

.contact-social-card:hover span {
    color: var(--text-primary);
}

/* ===== Footer ===== */
.footer {
    padding: 30px 0;
    border-top: 1px solid var(--border-color);
    text-align: center;
}

.footer-content p {
    color: var(--text-muted);
    font-size: 0.85rem;
    margin-bottom: 4px;
}

.footer-content p:last-child {
    margin-bottom: 0;
}

/* ===== Back to Top ===== */
.back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 48px;
    height: 48px;
    border-radius: var(--radius-full);
    background: var(--gradient-1);
    color: white;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.1rem;
    opacity: 0;
    visibility: hidden;
    transform: translateY(20px);
    transition: var(--transition);
    z-index: 999;
    box-shadow: 0 4px 20px rgba(108, 99, 255, 0.3);
}

.back-to-top.visible {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.back-to-top:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 30px rgba(108, 99, 255, 0.5);
}

/* ===== Animations ===== */
.fade-in {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

.fade-in.visible {
    opacity: 1;
    transform: translateY(0);
}

/* ===== Responsive ===== */
@media (max-width: 1024px) {
    .hero-content {
        gap: 40px;
    }

    .profile-container {
        width: 280px;
        height: 280px;
    }
}

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

    .nav-menu {
        position: fixed;
        top: 0;
        right: -100%;
        width: 280px;
        height: 100vh;
        background: rgba(12, 12, 29, 0.98);
        backdrop-filter: blur(20px);
        flex-direction: column;
        padding: 80px 30px 30px;
        gap: 4px;
        transition: var(--transition);
        border-left: 1px solid var(--border-color);
    }

    .nav-menu.active {
        right: 0;
    }

    .hero-content {
        grid-template-columns: 1fr;
        text-align: center;
        gap: 40px;
    }

    .hero-buttons {
        justify-content: center;
    }

    .hero-social {
        justify-content: center;
    }

    .hero-image {
        order: -1;
    }

    .profile-container {
        width: 220px;
        height: 220px;
    }

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

    .about-card.main-about {
        grid-column: span 1;
    }

    .about-stats {
        grid-template-columns: repeat(2, 1fr);
    }

    .position-cards {
        grid-template-columns: 1fr;
    }

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

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

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

    .contact-social-grid {
        grid-template-columns: 1fr;
    }

    .section {
        padding: 60px 0;
    }

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

    .scroll-indicator {
        display: none;
    }
}

@media (max-width: 480px) {
    .about-stats {
        grid-template-columns: 1fr;
    }

    .hero-buttons {
        flex-direction: column;
        align-items: center;
    }

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

    .pub-filter {
        gap: 8px;
    }

    .filter-btn {
        padding: 6px 14px;
        font-size: 0.8rem;
    }
}