/* ============================================
   PORTFOLIO -  Naresh Sekar
   Pure CSS · Dark Neural-Network Aesthetic
   ============================================ */

/* --- Custom Properties --- */
:root {
  --bg-primary: #0a0a0f;
  --bg-secondary: #12121a;
  --bg-card: rgba(255, 255, 255, 0.03);
  --bg-card-hover: rgba(255, 255, 255, 0.06);
  --glass: rgba(255, 255, 255, 0.05);
  --glass-border: rgba(255, 255, 255, 0.08);
  --accent: #7b2ff7;
  --accent-light: #9b5fff;
  --cyan: #00d4ff;
  --gradient: linear-gradient(135deg, #7b2ff7, #00d4ff);
  --gradient-warm: linear-gradient(135deg, #7b2ff7, #ff6b6b);
  --text-primary: #e8e8f0;
  --text-secondary: #8888a0;
  --text-muted: #55556a;
  --font-sans: 'Inter', system-ui, -apple-system, sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', monospace;
  --nav-height: 70px;
  --section-padding: 120px;
  --container-width: 1100px;
  --radius: 16px;
  --radius-sm: 10px;
  --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
  -webkit-text-size-adjust: 100%;
}

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

::selection {
  background: rgba(123, 47, 247, 0.4);
  color: #fff;
}

a {
  color: var(--cyan);
  text-decoration: none;
  transition: color var(--transition);
}

a:hover {
  color: var(--accent-light);
}

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

ul, ol {
  list-style: none;
}

button {
  font-family: inherit;
  cursor: pointer;
  border: none;
  background: none;
  color: inherit;
}

/* --- Utility --- */
.container {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 24px;
}

.section-number {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--accent);
  letter-spacing: 2px;
  margin-bottom: 8px;
  display: block;
}

.section-title {
  font-size: 2.4rem;
  font-weight: 800;
  margin-bottom: 16px;
  letter-spacing: -0.5px;
}

.section-subtitle {
  color: var(--text-secondary);
  font-size: 1.05rem;
  max-width: 560px;
  margin-bottom: 56px;
}

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

/* --- Scroll Reveal --- */
.reveal {
  opacity: 0;
  transform: translateY(32px);
  transition: opacity 0.7s cubic-bezier(0.4, 0, 0.2, 1),
              transform 0.7s cubic-bezier(0.4, 0, 0.2, 1);
}

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

/* Stagger children */
.reveal-group .reveal:nth-child(2) { transition-delay: 0.1s; }
.reveal-group .reveal:nth-child(3) { transition-delay: 0.2s; }
.reveal-group .reveal:nth-child(4) { transition-delay: 0.25s; }
.reveal-group .reveal:nth-child(5) { transition-delay: 0.3s; }
.reveal-group .reveal:nth-child(6) { transition-delay: 0.35s; }

/* ============================================
   01. NAVIGATION
   ============================================ */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: var(--nav-height);
  z-index: 1000;
  transition: background var(--transition), box-shadow var(--transition);
}

.nav.scrolled {
  background: rgba(10, 10, 15, 0.85);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  box-shadow: 0 1px 0 var(--glass-border);
}

.nav-inner {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 24px;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-logo {
  font-size: 1.5rem;
  font-weight: 800;
  letter-spacing: -1px;
  background: var(--gradient);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

.nav-links {
  display: flex;
  gap: 32px;
  align-items: center;
}

.nav-links a {
  color: var(--text-secondary);
  font-size: 0.9rem;
  font-weight: 500;
  transition: color var(--transition);
  position: relative;
}

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--gradient);
  transition: width var(--transition);
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--text-primary);
}

.nav-links a.active::after,
.nav-links a:hover::after {
  width: 100%;
}

/* Hamburger */
.hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  width: 28px;
  padding: 4px 0;
  z-index: 1001;
}

.hamburger span {
  display: block;
  height: 2px;
  width: 100%;
  background: var(--text-primary);
  border-radius: 2px;
  transition: transform var(--transition), opacity var(--transition);
}

.hamburger.open span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.hamburger.open span:nth-child(2) {
  opacity: 0;
}

.hamburger.open span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* Mobile overlay */
.mobile-menu {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(10, 10, 15, 0.97);
  backdrop-filter: blur(24px);
  -webkit-backdrop-filter: blur(24px);
  z-index: 999;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 28px;
  opacity: 0;
  transition: opacity var(--transition);
}

.mobile-menu.open {
  display: flex;
  opacity: 1;
}

.mobile-menu a {
  font-size: 1.4rem;
  font-weight: 600;
  color: var(--text-secondary);
  transition: color var(--transition);
}

.mobile-menu a:hover {
  color: var(--text-primary);
}

/* ============================================
   02. HERO
   ============================================ */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  position: relative;
  overflow: hidden;
  padding-top: var(--nav-height);
}

/* Animated gradient bg */
.hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background: radial-gradient(ellipse 80% 60% at 50% 40%, rgba(123, 47, 247, 0.12), transparent),
              radial-gradient(ellipse 60% 50% at 80% 20%, rgba(0, 212, 255, 0.08), transparent);
  animation: heroGlow 15s ease-in-out infinite alternate;
}

@keyframes heroGlow {
  0% { opacity: 1; transform: scale(1); }
  100% { opacity: 0.6; transform: scale(1.1); }
}

/* Dot grid */
.hero-dots {
  position: absolute;
  inset: 0;
  background-image: radial-gradient(rgba(255, 255, 255, 0.06) 1px, transparent 1px);
  background-size: 40px 40px;
  pointer-events: none;
}

/* Floating shapes */
.hero-shapes {
  position: absolute;
  inset: 0;
  pointer-events: none;
}

.shape {
  position: absolute;
  border-radius: 50%;
  opacity: 0.15;
}

.shape-1 {
  width: 300px;
  height: 300px;
  background: var(--accent);
  top: 10%;
  right: -5%;
  filter: blur(80px);
  animation: float1 8s ease-in-out infinite;
}

.shape-2 {
  width: 200px;
  height: 200px;
  background: var(--cyan);
  bottom: 20%;
  left: -3%;
  filter: blur(60px);
  animation: float2 10s ease-in-out infinite;
}

.shape-3 {
  width: 150px;
  height: 150px;
  background: linear-gradient(135deg, var(--accent), var(--cyan));
  top: 50%;
  left: 60%;
  filter: blur(50px);
  animation: float3 12s ease-in-out infinite;
}

@keyframes float1 {
  0%, 100% { transform: translate(0, 0) scale(1); }
  50% { transform: translate(-30px, 20px) scale(1.05); }
}

@keyframes float2 {
  0%, 100% { transform: translate(0, 0) scale(1); }
  50% { transform: translate(20px, -30px) scale(1.08); }
}

@keyframes float3 {
  0%, 100% { transform: translate(0, 0); }
  50% { transform: translate(-20px, -20px); }
}

.hero-content {
  position: relative;
  z-index: 2;
  width: 100%;
}

.hero-grid {
  display: flex;
  align-items: center;
  gap: 60px;
}

/* Profile photo */
.hero-photo {
  flex-shrink: 0;
}

.hero-photo-wrap {
  width: 200px;
  height: 200px;
  border-radius: 50%;
  padding: 4px;
  background: var(--gradient);
  box-shadow: 0 0 40px rgba(123, 47, 247, 0.3), 0 0 80px rgba(0, 212, 255, 0.1);
  animation: photoGlow 4s ease-in-out infinite alternate;
}

@keyframes photoGlow {
  0% { box-shadow: 0 0 40px rgba(123, 47, 247, 0.3), 0 0 80px rgba(0, 212, 255, 0.1); }
  100% { box-shadow: 0 0 60px rgba(123, 47, 247, 0.4), 0 0 100px rgba(0, 212, 255, 0.15); }
}

.hero-photo-wrap img {
  width: 100%;
  height: 100%;
  border-radius: 50%;
  object-fit: cover;
  display: block;
}

/* Photo placeholder when no image */
.hero-photo-placeholder {
  width: 100%;
  height: 100%;
  border-radius: 50%;
  background: var(--bg-secondary);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 3rem;
  font-weight: 800;
  background: linear-gradient(135deg, var(--bg-secondary), #1a1a2e);
  color: var(--accent-light);
}

.hero-text {
  flex: 1;
}

.hero-label {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--cyan);
  margin-bottom: 12px;
  letter-spacing: 2px;
  opacity: 0;
  animation: fadeInUp 0.6s 0.3s forwards;
}

.hero-name {
  font-size: 3.8rem;
  font-weight: 800;
  letter-spacing: -2px;
  line-height: 1.1;
  margin-bottom: 8px;
  opacity: 0;
  animation: fadeInUp 0.6s 0.5s forwards;
}

.hero-tagline {
  font-size: 1.35rem;
  color: var(--text-secondary);
  margin-bottom: 24px;
  min-height: 2rem;
  opacity: 0;
  animation: fadeInUp 0.6s 0.7s forwards;
}

.hero-tagline .cursor {
  display: inline-block;
  width: 2px;
  height: 1.2em;
  background: var(--cyan);
  margin-left: 2px;
  vertical-align: text-bottom;
  animation: blink 1s step-end infinite;
}

@keyframes blink {
  50% { opacity: 0; }
}

@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(24px); }
  to { opacity: 1; transform: translateY(0); }
}

/* Stats */
.hero-stats {
  display: flex;
  gap: 36px;
  margin-bottom: 32px;
  opacity: 0;
  animation: fadeInUp 0.6s 0.9s forwards;
}

.hero-stat-number {
  font-size: 1.8rem;
  font-weight: 800;
  background: var(--gradient);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-stat-label {
  font-size: 0.78rem;
  color: var(--text-muted);
  font-family: var(--font-mono);
  letter-spacing: 0.5px;
}

/* CTA buttons */
.hero-ctas {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
  opacity: 0;
  animation: fadeInUp 0.6s 1.1s forwards;
}

.btn-primary {
  padding: 14px 32px;
  background: var(--gradient);
  color: #fff;
  font-weight: 600;
  font-size: 0.95rem;
  border-radius: 50px;
  transition: transform var(--transition), box-shadow var(--transition);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 30px rgba(123, 47, 247, 0.35);
  color: #fff;
}

.btn-secondary {
  padding: 14px 32px;
  border: 1px solid var(--glass-border);
  color: var(--text-primary);
  font-weight: 600;
  font-size: 0.95rem;
  border-radius: 50px;
  transition: all var(--transition);
  background: var(--glass);
}

.btn-secondary:hover {
  border-color: var(--accent);
  background: rgba(123, 47, 247, 0.1);
  color: #fff;
}

/* Scroll indicator */
.scroll-indicator {
  position: absolute;
  bottom: 32px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  opacity: 0;
  animation: fadeInUp 0.6s 1.5s forwards;
}

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

.scroll-mouse::after {
  content: '';
  position: absolute;
  top: 6px;
  left: 50%;
  transform: translateX(-50%);
  width: 3px;
  height: 8px;
  background: var(--accent);
  border-radius: 2px;
  animation: scrollWheel 2s ease-in-out infinite;
}

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

.scroll-text {
  font-size: 0.7rem;
  color: var(--text-muted);
  font-family: var(--font-mono);
  letter-spacing: 1px;
}

/* ============================================
   03. ABOUT
   ============================================ */
.about {
  padding: var(--section-padding) 0;
}

.about-mission {
  font-size: 1.2rem;
  line-height: 1.9;
  color: var(--text-secondary);
  border-left: 3px solid;
  border-image: var(--gradient) 1;
  padding-left: 24px;
  margin-bottom: 56px;
  max-width: 700px;
}

.about-cards {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.about-card {
  background: var(--bg-card);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius);
  padding: 32px 28px;
  transition: all var(--transition);
}

.about-card:hover {
  background: var(--bg-card-hover);
  border-color: rgba(123, 47, 247, 0.2);
  transform: translateY(-4px);
}

.about-card-icon {
  width: 48px;
  height: 48px;
  border-radius: 12px;
  background: rgba(123, 47, 247, 0.1);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
  color: var(--accent-light);
}

.about-card h3 {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 10px;
}

.about-card p {
  color: var(--text-secondary);
  font-size: 0.92rem;
  line-height: 1.7;
}

/* ============================================
   04. CAREER TIMELINE
   ============================================ */
.career {
  padding: var(--section-padding) 0;
  background: var(--bg-secondary);
}

.timeline {
  position: relative;
  max-width: 900px;
  margin: 0 auto;
}

/* Vertical line */
.timeline::before {
  content: '';
  position: absolute;
  left: 50%;
  top: 0;
  bottom: 0;
  width: 2px;
  background: linear-gradient(180deg, var(--cyan), var(--accent), #ff6b6b);
  transform: translateX(-50%);
}

.timeline-item {
  position: relative;
  width: 50%;
  padding: 0 40px 60px;
}

.timeline-item:nth-child(odd) {
  left: 0;
  text-align: right;
  padding-right: 60px;
  padding-left: 0;
}

.timeline-item:nth-child(even) {
  left: 50%;
  text-align: left;
  padding-left: 60px;
  padding-right: 0;
}

/* Timeline dot */
.timeline-dot {
  position: absolute;
  top: 8px;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--accent);
  border: 3px solid var(--bg-secondary);
  z-index: 2;
}

.timeline-item:nth-child(odd) .timeline-dot {
  right: -7px;
}

.timeline-item:nth-child(even) .timeline-dot {
  left: -7px;
}

.timeline-dot.current {
  background: var(--cyan);
  box-shadow: 0 0 16px rgba(0, 212, 255, 0.5);
  animation: pulseDot 2s ease-in-out infinite;
}

@keyframes pulseDot {
  0%, 100% { box-shadow: 0 0 16px rgba(0, 212, 255, 0.5); }
  50% { box-shadow: 0 0 28px rgba(0, 212, 255, 0.8); }
}

.timeline-card {
  background: var(--bg-card);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius);
  padding: 28px;
  text-align: left;
  transition: all var(--transition);
}

.timeline-card:hover {
  background: var(--bg-card-hover);
  border-color: rgba(123, 47, 247, 0.2);
}

.timeline-date {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--cyan);
  margin-bottom: 8px;
}

.timeline-role {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 4px;
}

.timeline-company {
  color: var(--accent-light);
  font-size: 0.95rem;
  margin-bottom: 6px;
}

.timeline-location {
  font-size: 0.8rem;
  color: var(--text-muted);
  margin-bottom: 12px;
}

.timeline-summary {
  color: var(--text-secondary);
  font-size: 0.9rem;
  line-height: 1.7;
  margin-bottom: 12px;
}

.timeline-expand-btn {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--cyan);
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  transition: color var(--transition);
}

.timeline-expand-btn:hover {
  color: var(--accent-light);
}

.timeline-expand-btn svg {
  width: 14px;
  height: 14px;
  transition: transform var(--transition);
}

.timeline-expand-btn[aria-expanded="true"] svg {
  transform: rotate(180deg);
}

.timeline-details {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}

.timeline-details-inner {
  padding-top: 16px;
}

.timeline-achievements {
  margin-bottom: 12px;
}

.timeline-achievements li {
  color: var(--text-secondary);
  font-size: 0.88rem;
  line-height: 1.7;
  padding-left: 16px;
  position: relative;
  margin-bottom: 6px;
}

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

.timeline-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}

.timeline-tag {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  padding: 4px 10px;
  background: rgba(123, 47, 247, 0.1);
  border: 1px solid rgba(123, 47, 247, 0.2);
  border-radius: 20px;
  color: var(--accent-light);
}

/* ============================================
   05. TECHNICAL SKILLS
   ============================================ */
.skills {
  padding: var(--section-padding) 0;
}

.skills-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 28px;
}

.skill-category {
  background: var(--bg-card);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius);
  padding: 32px;
  transition: all var(--transition);
}

.skill-category:hover {
  border-color: rgba(123, 47, 247, 0.2);
}

.skill-category h3 {
  font-size: 1.05rem;
  font-weight: 700;
  margin-bottom: 24px;
  display: flex;
  align-items: center;
  gap: 10px;
}

.skill-category h3 svg {
  width: 20px;
  height: 20px;
  color: var(--accent-light);
}

.skill-item {
  margin-bottom: 18px;
}

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

.skill-header {
  display: flex;
  justify-content: space-between;
  margin-bottom: 6px;
}

.skill-name {
  font-size: 0.88rem;
  font-weight: 500;
}

.skill-level {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--text-muted);
}

.skill-bar {
  height: 6px;
  background: rgba(255, 255, 255, 0.06);
  border-radius: 3px;
  overflow: hidden;
}

.skill-fill {
  height: 100%;
  width: 0%;
  background: var(--gradient);
  border-radius: 3px;
  transition: width 1.2s cubic-bezier(0.4, 0, 0.2, 1);
}

.skill-fill.animated {
  /* width set via data-width attribute in JS */
}

/* ============================================
   06. LEADERSHIP
   ============================================ */
.leadership {
  padding: var(--section-padding) 0;
  background: var(--bg-secondary);
}

.leadership-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.leadership-card {
  background: var(--bg-card);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius);
  padding: 32px 28px;
  position: relative;
  overflow: hidden;
  transition: all var(--transition);
}

.leadership-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: var(--gradient);
  opacity: 0.6;
  transition: opacity var(--transition);
}

.leadership-card:hover {
  transform: translateY(-6px);
  background: var(--bg-card-hover);
  box-shadow: 0 16px 48px rgba(123, 47, 247, 0.1);
}

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

.leadership-card-icon {
  width: 44px;
  height: 44px;
  border-radius: 10px;
  background: rgba(123, 47, 247, 0.1);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
  color: var(--accent-light);
}

.leadership-card h3 {
  font-size: 1.05rem;
  font-weight: 700;
  margin-bottom: 10px;
}

.leadership-card p {
  color: var(--text-secondary);
  font-size: 0.9rem;
  line-height: 1.7;
}

/* ============================================
   07. PUBLICATIONS
   ============================================ */
.publications {
  padding: var(--section-padding) 0;
}

.pub-content {
  display: flex;
  align-items: center;
  gap: 60px;
}

/* 3D Book */
.book-3d {
  flex-shrink: 0;
  perspective: 800px;
}

.book-wrap {
  width: 200px;
  height: 280px;
  position: relative;
  transform-style: preserve-3d;
  transform: rotateY(-25deg);
  transition: transform 0.6s cubic-bezier(0.4, 0, 0.2, 1);
}

.book-3d:hover .book-wrap {
  transform: rotateY(-10deg);
}

.book-front {
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, #1a1a2e, #2d1b69);
  border-radius: 4px 12px 12px 4px;
  padding: 24px 20px;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  text-align: center;
  box-shadow: 5px 5px 20px rgba(0, 0, 0, 0.5);
  border: 1px solid rgba(123, 47, 247, 0.3);
  transform: translateZ(12px);
}

.book-front-title {
  font-size: 0.95rem;
  font-weight: 700;
  line-height: 1.4;
  margin-bottom: 12px;
}

.book-front-author {
  font-size: 0.75rem;
  color: var(--text-secondary);
  font-family: var(--font-mono);
}

.book-spine {
  position: absolute;
  top: 0;
  left: 0;
  width: 24px;
  height: 100%;
  background: linear-gradient(180deg, #2d1b69, #1a1a2e);
  transform: rotateY(90deg) translateZ(0px) translateX(-12px);
  border-radius: 4px 0 0 4px;
}

.book-side {
  position: absolute;
  top: 0;
  left: 0;
  width: 200px;
  height: 280px;
  background: #12121a;
  border-radius: 4px 12px 12px 4px;
  transform: translateZ(-12px);
}

.pub-info {
  flex: 1;
}

.pub-info h3 {
  font-size: 1.3rem;
  font-weight: 700;
  margin-bottom: 8px;
}

.pub-info .pub-author {
  color: var(--accent-light);
  font-size: 0.95rem;
  margin-bottom: 16px;
}

.pub-info .pub-desc {
  color: var(--text-secondary);
  font-size: 0.95rem;
  line-height: 1.8;
  margin-bottom: 20px;
}

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

/* ============================================
   08. CERTIFICATIONS
   ============================================ */
.certifications {
  padding: var(--section-padding) 0;
  background: var(--bg-secondary);
}

.certs-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
}

.cert-card {
  background: var(--bg-card);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-sm);
  padding: 24px 28px;
  display: flex;
  align-items: center;
  gap: 20px;
  transition: all var(--transition);
}

.cert-card:hover {
  background: var(--bg-card-hover);
  transform: translateY(-2px);
}

.cert-accent {
  width: 4px;
  height: 48px;
  border-radius: 2px;
  background: var(--gradient);
  flex-shrink: 0;
}

.cert-info h3 {
  font-size: 0.95rem;
  font-weight: 700;
  margin-bottom: 4px;
}

.cert-info p {
  color: var(--text-secondary);
  font-size: 0.82rem;
}

/* ============================================
   09. EDUCATION
   ============================================ */
.education {
  padding: var(--section-padding) 0;
}

.edu-card {
  max-width: 580px;
  background: var(--bg-card);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius);
  padding: 36px 40px;
}

.edu-degree {
  font-size: 1.2rem;
  font-weight: 700;
  margin-bottom: 6px;
}

.edu-school {
  color: var(--accent-light);
  font-size: 1rem;
  margin-bottom: 4px;
}

.edu-meta {
  color: var(--text-muted);
  font-family: var(--font-mono);
  font-size: 0.82rem;
}

/* ============================================
   10. CONTACT
   ============================================ */
.contact {
  padding: var(--section-padding) 0;
  background: var(--bg-secondary);
}

.contact-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.contact-card {
  display: flex;
  align-items: center;
  gap: 16px;
  background: var(--bg-card);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-sm);
  padding: 22px 24px;
  transition: all var(--transition);
  text-decoration: none;
  color: var(--text-primary);
}

.contact-card:hover {
  background: var(--bg-card-hover);
  border-color: rgba(123, 47, 247, 0.3);
  transform: translateY(-3px);
  box-shadow: 0 8px 24px rgba(123, 47, 247, 0.1);
  color: var(--text-primary);
}

.contact-icon {
  width: 44px;
  height: 44px;
  border-radius: 10px;
  background: rgba(123, 47, 247, 0.1);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  color: var(--accent-light);
}

.contact-icon svg {
  width: 20px;
  height: 20px;
}

.contact-label {
  font-size: 0.82rem;
  color: var(--text-muted);
  font-family: var(--font-mono);
}

.contact-name {
  font-weight: 600;
  font-size: 0.95rem;
}

/* ============================================
   FOOTER
   ============================================ */
.footer {
  padding: 40px 0;
  border-top: 1px solid var(--glass-border);
}

.footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.footer-copy {
  color: var(--text-muted);
  font-size: 0.82rem;
}

.footer-tagline {
  color: var(--text-muted);
  font-size: 0.78rem;
  font-family: var(--font-mono);
}

/* Back to top */
.back-to-top {
  position: fixed;
  bottom: 32px;
  right: 32px;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: var(--glass);
  border: 1px solid var(--glass-border);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-secondary);
  opacity: 0;
  visibility: hidden;
  transform: translateY(10px);
  transition: all var(--transition);
  z-index: 100;
}

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

.back-to-top:hover {
  background: rgba(123, 47, 247, 0.2);
  border-color: var(--accent);
  color: var(--text-primary);
}

.back-to-top svg {
  width: 18px;
  height: 18px;
}

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

/* --- Tablet (≤1024px) --- */
@media (max-width: 1024px) {
  :root {
    --section-padding: 90px;
  }

  .section-title {
    font-size: 2rem;
  }

  /* Timeline single-column */
  .timeline::before {
    left: 20px;
  }

  .timeline-item,
  .timeline-item:nth-child(odd),
  .timeline-item:nth-child(even) {
    width: 100%;
    left: 0;
    text-align: left;
    padding-left: 56px;
    padding-right: 0;
  }

  .timeline-item:nth-child(odd) .timeline-dot,
  .timeline-item:nth-child(even) .timeline-dot {
    left: 13px;
    right: auto;
  }

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

  .pub-content {
    gap: 40px;
  }
}

/* --- Mobile (≤768px) --- */
@media (max-width: 768px) {
  :root {
    --section-padding: 72px;
    --nav-height: 60px;
  }

  .section-title {
    font-size: 1.7rem;
  }

  .section-subtitle {
    margin-bottom: 40px;
  }

  /* Nav */
  .nav-links {
    display: none;
  }

  .hamburger {
    display: flex;
  }

  /* Hero */
  .hero-grid {
    flex-direction: column;
    text-align: center;
  }

  .hero-name {
    font-size: 2.4rem;
  }

  .hero-photo-wrap {
    width: 160px;
    height: 160px;
  }

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

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

  /* About */
  .about-cards {
    grid-template-columns: 1fr;
  }

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

  /* Leadership */
  .leadership-grid {
    grid-template-columns: 1fr;
  }

  /* Publications */
  .pub-content {
    flex-direction: column;
    text-align: center;
    gap: 40px;
  }

  .pub-links {
    justify-content: center;
  }

  /* Certs */
  .certs-grid {
    grid-template-columns: 1fr;
  }

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

  /* Footer */
  .footer-inner {
    flex-direction: column;
    gap: 12px;
    text-align: center;
  }
}

/* --- Small Mobile (≤480px) --- */
@media (max-width: 480px) {
  :root {
    --section-padding: 56px;
  }

  .hero-name {
    font-size: 2rem;
  }

  .hero-tagline {
    font-size: 1.1rem;
  }

  .hero-stats {
    gap: 20px;
  }

  .hero-stat-number {
    font-size: 1.4rem;
  }

  /* Hide decorative shapes */
  .hero-shapes {
    display: none;
  }

  .hero-photo-wrap {
    width: 130px;
    height: 130px;
  }

  .btn-primary,
  .btn-secondary {
    padding: 12px 24px;
    font-size: 0.88rem;
  }

  .scroll-indicator {
    display: none;
  }
}

/* --- Reduced Motion --- */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }

  .reveal {
    opacity: 1;
    transform: none;
  }

  .skill-fill {
    transition: none;
  }
}