/* ========================================
   DESIGN SYSTEM
======================================== */
:root {
  --bg: #f0f8ff;
  --bg-soft: #e8f4fd;
  --bg-card: #ffffff;
  --text-primary: #0f172a;
  --text-secondary: #475569;
  --text-muted: #94a3b8;
  --accent: #0ea5e9;
  --accent-dark: #0284c7;
  --accent-light: #e0f2fe;
  --accent-purple: #7c3aed;
  --accent-green: #059669;
  --accent-yellow: #d97706;
  --border: #e2e8f0;
  --nav-height: 70px;
  --radius: 12px;
  --radius-lg: 20px;
  --shadow: 0 4px 20px rgba(0, 0, 0, 0.06);
  --shadow-hover: 0 12px 40px rgba(14, 165, 233, 0.15);
  --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: 'Inter', 'Segoe UI', sans-serif;
  background: var(--bg);
  color: var(--text-primary);
  line-height: 1.6;
  padding-top: var(--nav-height);
  min-height: 100vh;
}

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

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

ul {
  list-style: none;
}

/* ========================================
   MOLECULAR CANVAS BACKGROUND
======================================== */
#mol-bg {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: 0;
  pointer-events: none;
}

/* All page chrome sits above canvas */
.page-transition {
  z-index: 9999;
}

.nav {
  z-index: 1000;
}

.hero {
  z-index: 1;
  position: relative;
}

.page-banner,
.section,
footer {
  position: relative;
  z-index: 1;
}


/* ========================================
   PAGE TRANSITION
======================================== */
.page-transition {
  position: fixed;
  inset: 0;
  background: #ffffff;
  z-index: 9999;
  opacity: 1;
  pointer-events: none;
  transition: opacity 0.45s ease;
}

.page-transition.loaded {
  opacity: 0;
}

/* ========================================
   NAVIGATION
======================================== */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: var(--nav-height);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 48px;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border);
  z-index: 1000;
  box-sizing: border-box;
}

.nav-brand {
  font-family: 'Outfit', sans-serif;
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-primary);
  letter-spacing: -0.5px;
}

.nav-brand span {
  color: var(--accent);
}

.nav ul {
  display: flex;
  gap: 4px;
}

.nav a {
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--text-secondary);
  padding: 8px 14px;
  border-radius: 8px;
  transition: all var(--transition);
}

.nav a:hover,
.nav a.active {
  color: var(--accent);
  background: var(--accent-light);
}

/* ========================================
   HERO
======================================== */
.hero {
  position: relative;
  height: calc(100vh - var(--nav-height));
  min-height: 600px;
  display: flex;
  align-items: center;
  overflow: visible;
  background: transparent;
}

.hero-content {
  position: relative;
  z-index: 2;
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 48px;
  width: 100%;
}

.hero-eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: var(--accent-light);
  color: var(--accent-dark);
  font-size: 0.85rem;
  font-weight: 600;
  padding: 6px 14px;
  border-radius: 100px;
  margin-bottom: 24px;
  letter-spacing: 0.3px;
}

.hero-eyebrow::before {
  content: '';
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--accent);
  animation: pulse-dot 2s infinite;
}

@keyframes pulse-dot {

  0%,
  100% {
    transform: scale(1);
    opacity: 1;
  }

  50% {
    transform: scale(1.4);
    opacity: 0.6;
  }
}

.hero-content h1 {
  font-family: 'Outfit', sans-serif;
  font-size: clamp(2.5rem, 5vw, 4.2rem);
  font-weight: 800;
  line-height: 1.1;
  letter-spacing: -1.5px;
  color: var(--text-primary);
  margin-bottom: 16px;
}

.hero-content h1 .highlight {
  color: var(--accent);
}

.hero-subtitle {
  font-size: 1.2rem;
  color: var(--text-secondary);
  max-width: 560px;
  margin-bottom: 12px;
  font-weight: 400;
}

.hero-institution {
  font-size: 0.95rem;
  color: var(--text-muted);
  margin-bottom: 36px;
}

.hero-institution strong {
  color: var(--text-secondary);
  font-weight: 600;
}

.hero-actions {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}

.hero-stats {
  display: flex;
  gap: 40px;
  margin-top: 56px;
  padding-top: 40px;
  border-top: 1px solid var(--border);
}

.stat-item {
  display: flex;
  flex-direction: column;
}

.stat-number {
  font-family: 'Outfit', sans-serif;
  font-size: 2rem;
  font-weight: 800;
  color: var(--accent);
  line-height: 1;
  margin-bottom: 4px;
}

.stat-label {
  font-size: 0.8rem;
  color: var(--text-muted);
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

/* ========================================
   BUTTONS
======================================== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 28px;
  border-radius: 10px;
  font-weight: 600;
  font-size: 0.95rem;
  transition: all var(--transition);
  cursor: pointer;
  border: 2px solid transparent;
}

.btn-primary {
  background: var(--accent);
  color: white;
  border-color: var(--accent);
}

.btn-primary:hover {
  background: var(--accent-dark);
  border-color: var(--accent-dark);
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(14, 165, 233, 0.35);
}

.btn-outline {
  background: transparent;
  color: var(--text-primary);
  border-color: var(--border);
}

.btn-outline:hover {
  border-color: var(--accent);
  color: var(--accent);
  transform: translateY(-2px);
}

/* ========================================
   PAGE HEADER BANNER
======================================== */
.page-banner {
  background: var(--bg-soft);
  border-bottom: 1px solid var(--border);
  padding: 40px 48px 20px;
}

.page-banner-inner {
  max-width: 1100px;
  margin: 0 auto;
}

.page-tag {
  font-size: 0.8rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 1.5px;
  color: var(--accent);
  margin-bottom: 12px;
}

.page-banner h1 {
  font-family: 'Outfit', sans-serif;
  font-size: clamp(2rem, 4vw, 3rem);
  font-weight: 800;
  color: var(--text-primary);
  letter-spacing: -1px;
  margin-bottom: 12px;
}

.page-banner p {
  font-size: 1.05rem;
  color: var(--text-secondary);
  max-width: 600px;
}

/* ========================================
   SECTIONS
======================================== */
.section {
  max-width: 1100px;
  margin: 0 auto;
  padding: 80px 48px;
}

.section-header {
  margin-bottom: 48px;
}

.section-header h2 {
  font-family: 'Outfit', sans-serif;
  font-size: 2rem;
  font-weight: 800;
  color: var(--text-primary);
  letter-spacing: -0.5px;
  margin-bottom: 8px;
}

.section-header p {
  color: var(--text-secondary);
  font-size: 1rem;
}

/* ========================================
   CARDS (Research / ML Projects)
======================================== */
.cards-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 28px;
}

.card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: all var(--transition);
  box-shadow: var(--shadow);
}

.card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-hover);
  border-color: var(--accent);
}

.card-image {
  width: 100%;
  height: 200px;
  object-fit: cover;
}

.card-body {
  padding: 28px;
}

.card-tag {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 1px;
  color: var(--accent);
  background: var(--accent-light);
  padding: 4px 10px;
  border-radius: 6px;
  margin-bottom: 14px;
}

.card-body h3 {
  font-family: 'Outfit', sans-serif;
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 10px;
  line-height: 1.3;
}

.card-body p {
  font-size: 0.92rem;
  color: var(--text-secondary);
  line-height: 1.6;
  margin-bottom: 20px;
}

.card-link {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--accent);
  display: inline-flex;
  align-items: center;
  gap: 6px;
  transition: gap var(--transition);
}

.card-link:hover {
  gap: 10px;
}

/* ========================================
   ABOUT PAGE LAYOUT
======================================== */
.about-grid {
  display: grid;
  grid-template-columns: 300px 1fr;
  gap: 60px;
  align-items: start;
}

.profile-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow);
  position: sticky;
  top: calc(var(--nav-height) + 24px);
}

.profile-img {
  width: 100%;
  aspect-ratio: 1;
  object-fit: cover;
}

.profile-info {
  padding: 24px;
}

.profile-info h2 {
  font-family: 'Outfit', sans-serif;
  font-size: 1.4rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 4px;
}

.profile-info .title {
  font-size: 0.9rem;
  color: var(--accent);
  font-weight: 600;
  margin-bottom: 16px;
}

.profile-links {
  display: flex;
  flex-direction: column;
  gap: 10px;
  margin-top: 16px;
}

.profile-link {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 0.88rem;
  color: var(--text-secondary);
  transition: color var(--transition);
}

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

.profile-link i {
  width: 16px;
  text-align: center;
  color: var(--text-muted);
}

.timeline-body h4 {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 4px 12px;
}

.timeline-duration {
  font-size: 0.8rem;
  font-weight: 500;
  color: var(--text-muted);
  white-space: nowrap;
  margin-left: auto;
}

/* Thesis styling */
.timeline-body .thesis {
  font-size: 0.85rem;
  color: var(--text-secondary);
  margin-top: 6px;
  line-height: 1.5;
}

/* Advisor styling */
.timeline-body .advisor {
  font-size: 0.82rem;
  color: var(--text-muted);
  margin-top: 2px;
}

.expertise-section {
  margin-top: 20px;
}

/* Section headings */
/* ========================================
   TECHNICAL EXPERTISE SECTION
======================================== */

.expertise-section {
  margin-top: 24px;
}

/* Category Headings with Icons */
.expertise-section h4 {
  display: flex;
  align-items: center;
  gap: 10px;

  margin-top: 36px;
  margin-bottom: 16px;

  font-size: 1.05rem;
  font-weight: 600;
  letter-spacing: 0.4px;

  color: var(--text-muted) !important;

  border-left: 3px solid var(--accent);
  padding-left: 12px;
}

/* Icon styling */
.expertise-section h4 i {
  color: var(--accent);
  font-size: 0.95rem;
  min-width: 18px;
}

/* Tags container */
.expertise-section .tags {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-bottom: 14px;
  margin-top: 6px;
}

/* Default tag (light theme optimized) */
.expertise-section .tag {
  padding: 6px 14px;
  font-size: 0.82rem;
  font-weight: 500;

  border-radius: 999px;

  background: var(--bg-soft);
  color: var(--text-secondary);

  border: 1px solid var(--border);

  transition: all 0.25s ease;
}

/* Hover effect */
.expertise-section .tag:hover {
  border-color: var(--accent);
  color: var(--accent);
  background: var(--accent-light);
  transform: translateY(-2px);
}

/* Accent tags (your core strengths) */
.expertise-section .tag.accent {
  background: var(--accent);
  color: white;
  border-color: var(--accent);
  font-weight: 600;
}

/* Accent hover */
.expertise-section .tag.accent:hover {
  background: var(--accent-dark);
  box-shadow: 0 4px 14px rgba(14, 165, 233, 0.25);
}

/* ========================================
   OPTIONAL: CATEGORY COLOR CODING
   (subtle visual grouping)
======================================== */

/* Materials */
.expertise-section h4:nth-of-type(1) i {
  color: #7c3aed;
}

/* Deposition */
.expertise-section h4:nth-of-type(2) i {
  color: #6366f1;
}

/* Characterization */
.expertise-section h4:nth-of-type(3) i {
  color: #0ea5e9;
}

/* Spectroscopy */
.expertise-section h4:nth-of-type(4) i {
  color: #0284c7;
}

/* Electrochemistry */
.expertise-section h4:nth-of-type(5) i {
  color: #059669;
}

/* Battery */
.expertise-section h4:nth-of-type(6) i {
  color: #16a34a;
}

/* Thermal */
.expertise-section h4:nth-of-type(7) i {
  color: #d97706;
}

/* Analytical */
.expertise-section h4:nth-of-type(8) i {
  color: #9333ea;
}

/* Programming */
.expertise-section h4:nth-of-type(9) i {
  color: #2563eb;
}

/* Software */
.expertise-section h4:nth-of-type(10) i {
  color: #475569;
}

.bio-section h3 {
  font-family: 'Outfit', sans-serif;
  font-size: 1.35rem;
  font-weight: 700;
  color: var(--text-primary);

  margin-top: 36px;
  margin-bottom: 12px;

  padding-bottom: 8px;

  letter-spacing: -0.2px;
  /* makes it look sharper */
  border-left: 3px solid var(--accent);
  padding-left: 10px;
  border-bottom: none;
}

.bio-section h3:first-child {
  margin-top: 0;
}

.bio-section p {
  font-size: 0.97rem;
  color: var(--text-secondary);
  line-height: 1.8;
  margin-bottom: 16px;

  text-align: justify;
  /* ✅ correct place */
}


/* Timeline */
.timeline {
  display: flex;
  flex-direction: column;
  gap: 0;
}

.timeline-item {
  display: flex;
  gap: 20px;
  padding-bottom: 28px;
  position: relative;
}

.timeline-item:not(:last-child)::after {
  content: '';
  position: absolute;
  left: 25px;
  top: 54px;
  width: 2px;
  background: var(--border);
  bottom: 0;
}

.timeline-dot {
  flex-shrink: 0;
  width: 50px;
  height: 50px;
  border-radius: 12px;
  background: var(--accent-light);
  color: var(--accent);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 800;
  font-size: 0.7rem;
  text-align: center;
  line-height: 1.2;
}

.timeline-dot img {
  width: 50px;
  height: 50px;
  object-fit: contain;
  filter: drop-shadow(0 2px 4px rgba(0, 0, 0, 0.15));
  border-radius: 20px;
  background: rgba(255, 255, 255, 0.08);
  backdrop-filter: blur(10px);
  border: 1px solid rgba(255, 255, 255, 0.15);
  display: flex;
  align-items: center;
  justify-content: center;
}

.timeline-body h4 {
  font-weight: 700;
  color: var(--text-primary);
  font-size: 0.97rem;
  margin-bottom: 2px;
}

.timeline-body .place {
  font-size: 0.88rem;
  color: var(--accent);
  font-weight: 600;
  margin-bottom: 2px;
}

.timeline-body p {
  font-size: 0.86rem;
  color: var(--text-muted);
}

/* ========================================
   PUBLICATIONS
======================================== */
.pub-list {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.pub-item {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px 32px;
  display: flex;
  gap: 24px;
  align-items: flex-start;
  transition: all var(--transition);
  box-shadow: var(--shadow);
}

.pub-item:hover {
  border-color: var(--accent);
  transform: translateX(4px);
  box-shadow: var(--shadow-hover);
}

.pub-year {
  flex-shrink: 0;
  width: 56px;
  height: 56px;
  background: var(--accent-light);
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 800;
  font-size: 0.85rem;
  color: var(--accent-dark);
  text-align: center;
  line-height: 1.2;
}

.pub-content {
  flex: 1;
}

.pub-journal {
  font-size: 0.8rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 1px;
  color: var(--accent);
  margin-bottom: 6px;
}

.pub-title {
  font-family: 'Outfit', sans-serif;
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 8px;
  line-height: 1.35;
}

.pub-authors {
  font-size: 0.88rem;
  color: var(--text-secondary);
  margin-bottom: 14px;
}

.pub-authors .me {
  font-weight: 700;
  color: var(--text-primary);
  background: var(--accent-light);
  padding: 1px 6px;
  border-radius: 4px;
}

.pub-doi {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--accent);
  border: 1px solid var(--accent-light);
  padding: 5px 14px;
  border-radius: 8px;
  transition: all var(--transition);
}

.pub-doi:hover {
  background: var(--accent);
  color: white;
  border-color: var(--accent);
}

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

.contact-info h3 {
  font-family: 'Outfit', sans-serif;
  font-size: 1.4rem;
  font-weight: 700;
  margin-bottom: 8px;
}

.contact-info p {
  color: var(--text-secondary);
  margin-bottom: 32px;
  font-size: 0.97rem;
}

.contact-item {
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 18px 20px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  margin-bottom: 14px;
  transition: all var(--transition);
  background: var(--bg-card);
  box-shadow: var(--shadow);
}

.contact-item:hover {
  border-color: var(--accent);
  box-shadow: var(--shadow-hover);
}

.contact-icon {
  width: 44px;
  height: 44px;
  border-radius: 10px;
  background: var(--accent-light);
  color: var(--accent);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.1rem;
  flex-shrink: 0;
}

.contact-item-text h4 {
  font-size: 0.8rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.8px;
  color: var(--text-muted);
  margin-bottom: 2px;
}

.contact-item-text p,
.contact-item-text a {
  font-size: 0.95rem;
  color: var(--text-primary);
  font-weight: 500;
  transition: color var(--transition);
}

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

/* ========================================
   SCROLL REVEAL ANIMATION
======================================== */
.reveal {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.65s ease, transform 0.65s ease;
}

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

/* Stagger children */
.reveal-stagger>* {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.5s ease, transform 0.5s ease;
}

.reveal-stagger.active>*:nth-child(1) {
  opacity: 1;
  transform: none;
  transition-delay: 0.05s;
}

.reveal-stagger.active>*:nth-child(2) {
  opacity: 1;
  transform: none;
  transition-delay: 0.12s;
}

.reveal-stagger.active>*:nth-child(3) {
  opacity: 1;
  transform: none;
  transition-delay: 0.19s;
}

.reveal-stagger.active>*:nth-child(4) {
  opacity: 1;
  transform: none;
  transition-delay: 0.26s;
}

.reveal-stagger.active>*:nth-child(5) {
  opacity: 1;
  transform: none;
  transition-delay: 0.33s;
}

.reveal-stagger.active>*:nth-child(6) {
  opacity: 1;
  transform: none;
  transition-delay: 0.40s;
}

.reveal-stagger.active>*:nth-child(n+7) {
  opacity: 1;
  transform: none;
  transition-delay: 0.47s;
}

/* ========================================
   FOOTER
======================================== */
footer {
  background: var(--text-primary);
  color: var(--text-muted);
  padding: 40px 48px;
}

.footer-inner {
  max-width: 1100px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 20px;
  flex-wrap: wrap;
}

.footer-brand {
  font-family: 'Outfit', sans-serif;
  font-size: 1rem;
  font-weight: 700;
  color: white;
}

.footer-links {
  display: flex;
  gap: 24px;
}

.footer-links a {
  font-size: 0.85rem;
  color: var(--text-muted);
  transition: color var(--transition);
}

.footer-links a:hover {
  color: var(--accent);
}

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

/* ========================================
   DIVIDER
======================================== */
.divider {
  border: none;
  border-top: 1px solid var(--border);
  margin: 0;
}

/* ========================================
   RESEARCH PAGE
======================================== */

/* Intro strip */
.research-intro {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 16px;
  margin-bottom: 72px;
}


.ri-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 20px 14px;
  text-align: center;
  box-shadow: var(--shadow);
  transition: all var(--transition);
}

.ri-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-hover);
  border-color: var(--accent);
}

.ri-icon {
  width: 48px;
  height: 48px;
  border-radius: 12px;
  background: var(--accent-light);
  color: var(--accent);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.3rem;
  margin: 0 auto 14px;
}

.ri-card h3 {
  font-family: 'Outfit', sans-serif;
  font-size: 1rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 6px;
}

.ri-card p {
  font-size: 0.82rem;
  color: var(--text-secondary);
  line-height: 1.5;
}

/* Research block */
.research-block {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 56px;
  align-items: start;
  margin-bottom: 80px;
  padding-bottom: 80px;
  border-bottom: 1px solid var(--border);
}

.research-block:last-of-type {
  border-bottom: none;
}

/* Reverse: swap columns — gallery appears LEFT, text appears RIGHT */
.research-block.reverse .rb-text {
  order: 2;
}

.research-block.reverse .rb-gallery {
  order: 1;
}

/* Text side */
.rb-text .card-tag {
  margin-bottom: 14px;
}

.rb-text h2 {
  font-family: 'Outfit', sans-serif;
  font-size: 1.9rem;
  font-weight: 800;
  color: var(--text-primary);
  letter-spacing: -0.5px;
  margin-bottom: 16px;
  line-height: 1.2;
}

.rb-text .rb-desc {
  color: var(--text-secondary);
  line-height: 1.8;
  margin-bottom: 24px;
  font-size: 0.97rem;
}

/* Findings list */
.rb-findings {
  background: var(--bg-soft);
  border-left: 3px solid var(--accent);
  border-radius: 0 var(--radius) var(--radius) 0;
  padding: 18px 20px;
  margin-bottom: 22px;
}

.rb-findings h4 {
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 1px;
  color: var(--accent);
  margin-bottom: 10px;
}

.rb-findings ul {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.rb-findings ul li {
  font-size: 0.88rem;
  color: var(--text-secondary);
  line-height: 1.5;
  padding-left: 18px;
  position: relative;
}

.rb-findings ul li::before {
  content: '→';
  position: absolute;
  left: 0;
  color: var(--accent);
  font-weight: 700;
}

/* Tags row */
.rb-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 24px;
}

.rb-tags .tag {
  padding: 5px 12px;
  font-size: 0.78rem;
  font-weight: 600;
  border-radius: 999px;
  background: var(--bg-soft);
  color: var(--text-secondary);
  border: 1px solid var(--border);
  transition: all 0.25s ease;
}

.rb-tags .tag:hover {
  border-color: var(--accent);
  color: var(--accent);
  background: var(--accent-light);
}

/* CTA row */
.rb-cta {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}

/* Image gallery side */
.rb-gallery {
  display: flex;
  flex-direction: column;
  gap: 14px;
}

/* Main image: 16:9 */
.rb-img-main {
  width: 100%;
  aspect-ratio: 16 / 9;
  object-fit: cover;
  border-radius: var(--radius-lg);
  box-shadow: 0 8px 30px rgba(0, 0, 0, 0.1);
  transition: transform 0.4s ease, box-shadow 0.4s ease;
  display: block;
}

.rb-img-main:hover {
  transform: scale(1.015);
  box-shadow: 0 16px 48px rgba(14, 165, 233, 0.15);
}

/* Thumb row: two 4:3 images side by side */
.rb-thumbs {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 14px;
}

.rb-img-thumb {
  width: 100%;
  aspect-ratio: 4 / 3;
  object-fit: cover;
  border-radius: var(--radius);
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.08);
  transition: transform 0.35s ease, box-shadow 0.35s ease;
  display: block;
}

.rb-img-thumb:hover {
  transform: scale(1.03);
  box-shadow: 0 8px 28px rgba(14, 165, 233, 0.15);
}

/* Image caption */
.rb-img-caption {
  font-size: 0.78rem;
  color: var(--text-muted);
  text-align: center;
  margin-top: -6px;
  font-style: italic;
}

/* Future directions */
.future-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.future-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 28px 24px;
  box-shadow: var(--shadow);
  transition: all var(--transition);
  position: relative;
  overflow: hidden;
}

.future-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--accent), var(--accent-purple));
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.4s ease;
}

.future-card:hover::before {
  transform: scaleX(1);
}

.future-card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-hover);
  border-color: var(--accent);
}

.future-icon {
  width: 44px;
  height: 44px;
  border-radius: 10px;
  background: var(--accent-light);
  color: var(--accent);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.1rem;
  margin-bottom: 16px;
}

.future-card h3 {
  font-family: 'Outfit', sans-serif;
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 8px;
}

.future-card p {
  font-size: 0.87rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* Collab CTA banner */
.collab-banner {
  background: linear-gradient(135deg, var(--accent) 0%, var(--accent-purple) 100%);
  border-radius: var(--radius-lg);
  padding: 48px 40px;
  text-align: center;
  color: white;
  margin-top: 16px;
}

.collab-banner h2 {
  font-family: 'Outfit', sans-serif;
  font-size: 1.8rem;
  font-weight: 800;
  margin-bottom: 12px;
}

.collab-banner p {
  font-size: 1rem;
  opacity: 0.9;
  max-width: 500px;
  margin: 0 auto 28px;
  line-height: 1.7;
}

.btn-white {
  background: white;
  color: var(--accent-dark);
  border-color: white;
  font-weight: 700;
}

.btn-white:hover {
  background: var(--accent-light);
  border-color: var(--accent-light);
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.2);
}

/* Research page responsive */
@media (max-width: 1100px) {
  .research-intro {
    grid-template-columns: repeat(3, 1fr);
  }
}

@media (max-width: 900px) {
  .research-intro {
    grid-template-columns: repeat(2, 1fr);
  }

  .research-block {
    grid-template-columns: 1fr;
    gap: 32px;
  }

  /* Reset column ordering on single-column layout */
  .research-block.reverse .rb-text {
    order: unset;
  }

  .research-block.reverse .rb-gallery {
    order: unset;
  }

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

@media (max-width: 600px) {
  .research-intro {
    grid-template-columns: 1fr 1fr;
  }

  .rb-thumbs {
    grid-template-columns: 1fr;
  }

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

/* ========================================
   ACTIVITIES PAGE
======================================== */

/* ── Training Timeline ── */
.act-timeline {
  display: flex;
  flex-direction: column;
  gap: 0;
}

.act-item {
  display: flex;
  gap: 20px;
  padding-bottom: 28px;
  position: relative;
}

.act-item:not(:last-child)::after {
  content: '';
  position: absolute;
  left: 25px;
  top: 54px;
  width: 2px;
  background: var(--border);
  bottom: 0;
}

.act-dot {
  flex-shrink: 0;
  width: 50px;
  height: 50px;
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.1rem;
  transition: transform var(--transition);
}

.act-dot:hover {
  transform: scale(1.1);
}

.act-body h4 {
  font-weight: 700;
  color: var(--text-primary);
  font-size: 0.97rem;
  margin-bottom: 2px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
}

.act-date {
  font-size: 0.8rem;
  font-weight: 500;
  color: var(--text-muted);
  white-space: nowrap;
}

.act-place {
  font-size: 0.88rem;
  color: var(--accent);
  font-weight: 600;
  display: flex;
  align-items: center;
  gap: 6px;
}

.act-place i {
  font-size: 0.78rem;
  color: var(--text-muted);
}

/* ── Teaching Assistant Grid ── */
.ta-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 20px;
}

.ta-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  box-shadow: var(--shadow);
  transition: all var(--transition);
  position: relative;
  overflow: hidden;
}

.ta-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--accent-purple), var(--accent));
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.4s ease;
}

.ta-card:hover::before {
  transform: scaleX(1);
}

.ta-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-hover);
  border-color: var(--accent);
}

.ta-semester {
  font-size: 0.78rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.8px;
  color: var(--accent);
  margin-bottom: 8px;
}

.ta-card h4 {
  font-family: 'Outfit', sans-serif;
  font-size: 1.02rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 8px;
  line-height: 1.35;
}

.ta-code {
  display: inline-block;
  font-size: 0.78rem;
  font-weight: 600;
  padding: 3px 10px;
  border-radius: 6px;
  background: var(--bg-soft);
  color: var(--text-secondary);
  border: 1px solid var(--border);
}

/* ── Conference List ── */
.conf-list {
  display: flex;
  flex-direction: column;
  gap: 18px;
}

.conf-item {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px 28px;
  display: flex;
  gap: 24px;
  align-items: flex-start;
  transition: all var(--transition);
  box-shadow: var(--shadow);
}

.conf-item:hover {
  border-color: var(--accent);
  transform: translateX(4px);
  box-shadow: var(--shadow-hover);
}

.conf-year {
  flex-shrink: 0;
  width: 54px;
  height: 54px;
  background: var(--accent-light);
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 800;
  font-size: 0.85rem;
  color: var(--accent-dark);
  line-height: 1.2;
}

.conf-body {
  flex: 1;
}

.conf-type {
  display: inline-block;
  font-size: 0.72rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.8px;
  padding: 3px 10px;
  border-radius: 6px;
  margin-bottom: 8px;
}

.conf-poster {
  background: #e0f2fe;
  color: #0284c7;
}

.conf-talk {
  background: #ede9fe;
  color: #7c3aed;
}

.conf-attended {
  background: #dcfce7;
  color: #059669;
}

.conf-body h4 {
  font-family: 'Outfit', sans-serif;
  font-size: 1rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 6px;
  line-height: 1.4;
}

.conf-body p {
  font-size: 0.88rem;
  color: var(--text-secondary);
  line-height: 1.5;
  margin-bottom: 8px;
}

.conf-date {
  font-size: 0.8rem;
  color: var(--text-muted);
  font-weight: 500;
}

.conf-date i {
  margin-right: 4px;
  font-size: 0.75rem;
}

/* ── Project Cards ── */
.proj-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 24px;
}

.proj-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 28px;
  box-shadow: var(--shadow);
  transition: all var(--transition);
  position: relative;
  overflow: hidden;
}

.proj-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--accent-green), var(--accent));
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.4s ease;
}

.proj-card:hover::before {
  transform: scaleX(1);
}

.proj-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-hover);
  border-color: var(--accent);
}

.proj-icon {
  width: 48px;
  height: 48px;
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.2rem;
  margin-bottom: 16px;
}

.proj-card h4 {
  font-family: 'Outfit', sans-serif;
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 10px;
}

.proj-card p {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.7;
  margin-bottom: 16px;
}

.proj-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.proj-tags .tag {
  padding: 4px 12px;
  font-size: 0.76rem;
  font-weight: 600;
  border-radius: 999px;
  background: var(--bg-soft);
  color: var(--text-secondary);
  border: 1px solid var(--border);
  transition: all 0.25s ease;
}

.proj-tags .tag:hover {
  border-color: var(--accent);
  color: var(--accent);
  background: var(--accent-light);
}

/* ── Extra-Curricular List ── */
.extra-list {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.extra-item {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 18px 22px;
  display: flex;
  align-items: center;
  gap: 16px;
  transition: all var(--transition);
  box-shadow: var(--shadow);
}

.extra-item:hover {
  border-color: var(--accent);
  box-shadow: var(--shadow-hover);
  transform: translateX(4px);
}

.extra-icon {
  flex-shrink: 0;
  width: 40px;
  height: 40px;
  border-radius: 10px;
  background: var(--accent-light);
  color: var(--accent);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.95rem;
}

.extra-body {
  flex: 1;
}

.extra-body h4 {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 1px;
}

.extra-body p {
  font-size: 0.85rem;
  color: var(--text-muted);
}

.extra-date {
  font-size: 0.8rem;
  font-weight: 500;
  color: var(--text-muted);
  white-space: nowrap;
}

/* ========================================
   RESPONSIVE
======================================== */
@media (max-width: 900px) {
  .nav {
    padding: 0 20px;
  }

  .nav ul {
    gap: 0;
  }

  .nav a {
    padding: 8px 10px;
    font-size: 0.85rem;
  }

  .hero-content,
  .page-banner,
  .section {
    padding-left: 20px;
    padding-right: 20px;
  }

  .hero-stats {
    gap: 24px;
    flex-wrap: wrap;
  }

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

  .profile-card {
    position: static;
  }

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

  .pub-item {
    flex-direction: column;
    gap: 16px;
  }

  .conf-item {
    flex-direction: column;
    gap: 14px;
  }

  .extra-item {
    flex-wrap: wrap;
  }

  .extra-date {
    width: 100%;
    padding-left: 56px;
    margin-top: -4px;
  }

  .act-body h4 {
    flex-direction: column;
    align-items: flex-start;
    gap: 4px;
  }
}

@media (max-width: 600px) {
  .hero-content h1 {
    font-size: 2.2rem;
  }

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

  footer {
    padding: 32px 20px;
  }

  .footer-inner {
    flex-direction: column;
    text-align: center;
  }

  /* Stack inline 2-col project grids */
  [style*="grid-template-columns: 1fr 1fr"] {
    grid-template-columns: 1fr !important;
  }

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

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

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

/* ========================================
   RESEARCH SECTION — ANIMATED BADGES
   Small thematic indicators, one per block.
   Touch nothing else.
======================================== */
.rb-live-badge {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  font-size: 0.74rem;
  font-weight: 700;
  padding: 5px 14px;
  border-radius: 999px;
  margin-bottom: 18px;
  letter-spacing: 0.4px;
  position: relative;
  overflow: hidden;
  cursor: default;
  user-select: none;
}

/* Shimmer sweep across every badge */
.rb-live-badge::after {
  content: '';
  position: absolute;
  top: 0;
  left: -120%;
  width: 60%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.4), transparent);
  animation: rb-shimmer 2.8s ease-in-out infinite;
}

@keyframes rb-shimmer {
  0% {
    left: -120%;
  }

  100% {
    left: 220%;
  }
}

/* ── Section 1: PEC Water Splitting — blue sun ── */
.rb-badge-solar {
  background: #e0f2fe;
  color: #0284c7;
  border: 1px solid #bae6fd;
}

.rb-badge-solar i {
  animation: rb-spin-slow 5s linear infinite;
  display: inline-block;
}

@keyframes rb-spin-slow {
  from {
    transform: rotate(0deg);
  }

  to {
    transform: rotate(360deg);
  }
}

/* ── Section 2: Perovskite LED — purple atom pulse ── */
.rb-badge-perov {
  background: #ede9fe;
  color: #7c3aed;
  border: 1px solid #ddd6fe;
}

.rb-badge-perov i {
  animation: rb-glow-pulse 2s ease-in-out infinite;
  display: inline-block;
}

@keyframes rb-glow-pulse {

  0%,
  100% {
    transform: scale(1);
    opacity: 1;
  }

  50% {
    transform: scale(1.35);
    opacity: 0.65;
  }
}

/* ── Section 3: Advanced Spectroscopy — pink wave ── */
.rb-badge-spectro {
  background: #fce7f3;
  color: #be185d;
  border: 1px solid #fbcfe8;
}

.rb-badge-spectro i {
  animation: rb-wave-scan 1.6s ease-in-out infinite;
  display: inline-block;
}

@keyframes rb-wave-scan {

  0%,
  100% {
    transform: scaleX(1) translateX(0);
  }

  25% {
    transform: scaleX(0.7) translateX(-2px);
  }

  75% {
    transform: scaleX(1.2) translateX(2px);
  }
}

/* ── Section 4: Battery R&D — green charge bounce ── */
.rb-badge-battery {
  background: #dcfce7;
  color: #059669;
  border: 1px solid #a7f3d0;
}

.rb-badge-battery i {
  animation: rb-charge-bounce 1.4s ease-in-out infinite;
  display: inline-block;
}

@keyframes rb-charge-bounce {

  0%,
  100% {
    transform: translateY(0);
  }

  40% {
    transform: translateY(-4px);
  }

  70% {
    transform: translateY(2px);
  }
}

/* ── Section 5: ML for Materials — amber neural throb ── */
.rb-badge-ml {
  background: #fef3c7;
  color: #b45309;
  border: 1px solid #fde68a;
}

.rb-badge-ml i {
  animation: rb-neural-throb 1.9s ease-in-out infinite;
  display: inline-block;
}

@keyframes rb-neural-throb {

  0%,
  100% {
    transform: scale(1);
  }

  30% {
    transform: scale(1.3);
  }

  60% {
    transform: scale(0.85);
  }
}