/* Light academic theme — navy + white (reference: classic portfolio) */
:root {
  --navy: #141b2d;
  --navy-hover: #1f2d4a;
  --page: #ffffff;
  --page-muted: #f6f7f9;
  --text: #1a1a1a;
  --text-muted: #5c5f66;
  --border: #e4e6eb;
  --shadow: 0 8px 30px rgba(20, 27, 45, 0.08);
  --shadow-hover: 0 12px 40px rgba(20, 27, 45, 0.12);
  --hero-overlay: rgba(20, 27, 45, 0.52);
  --accent-soft: #e8ecf4;
  --published: #1e3a5f;
}

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

body {
  font-family: 'Source Serif 4', Georgia, 'Times New Roman', serif;
  background-color: var(--page);
  color: var(--text);
  line-height: 1.65;
  overflow-x: hidden;
}

h1,
h2,
h3,
h4,
h5,
h6 {
  font-family: 'Playfair Display', Georgia, serif;
  font-weight: 600;
}

a {
  text-decoration: none;
  color: inherit;
  transition: color 0.2s ease, background-color 0.2s ease, border-color 0.2s ease;
}

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

.section-title {
  font-size: 2.25rem;
  text-align: center;
  margin-bottom: 2.75rem;
  position: relative;
  color: var(--navy);
  opacity: 0;
  transform: translateY(16px);
  animation: fadeUp 0.75s forwards;
}

.section-title::after {
  content: '';
  display: block;
  width: 48px;
  height: 3px;
  background: var(--navy);
  margin: 12px auto 0;
  border-radius: 1px;
}

.section-lead {
  text-align: center;
  font-family: 'Playfair Display', Georgia, serif;
  font-size: 1.35rem;
  font-weight: 600;
  color: var(--navy);
  max-width: 720px;
  margin: -1.5rem auto 3rem;
  line-height: 1.45;
}

.section-hr {
  border: none;
  height: 1px;
  background: var(--border);
  max-width: 200px;
  margin: 0 auto 2.5rem;
}

.glass-card {
  background: var(--page);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 1.75rem 2rem;
  box-shadow: var(--shadow);
  transition: transform 0.25s ease, box-shadow 0.25s ease;
}

.glass-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-hover);
}

/* Navigation */
nav {
  position: fixed;
  top: 0;
  width: 100%;
  z-index: 1000;
  background: rgba(255, 255, 255, 0.94);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
  padding: 0.85rem 0;
}

.nav-inner {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: 1rem;
  position: relative;
}

.nav-inner .logo {
  justify-self: start;
}

.nav-inner .nav-links {
  justify-self: center;
}

.nav-inner .nav-aside {
  justify-self: end;
}

.logo {
  display: inline-flex;
  align-items: center;
  gap: 0.65rem;
  font-weight: 700;
  font-size: 1.15rem;
  color: var(--navy);
  font-family: 'Playfair Display', Georgia, serif;
}

.logo-img {
  width: 36px;
  height: 36px;
  border-radius: 8px;
  object-fit: cover;
  border: 1px solid var(--border);
}

.logo-light {
  color: var(--text-muted);
  font-weight: 600;
}

.nav-links {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 1.35rem 1.75rem;
}

.nav-links a {
  font-size: 0.9rem;
  font-weight: 500;
  font-family: 'Source Serif 4', Georgia, serif;
  color: var(--text);
  position: relative;
}

.nav-links a:hover {
  color: var(--navy);
}

.nav-links a::after {
  content: '';
  position: absolute;
  width: 0;
  height: 2px;
  bottom: -5px;
  left: 0;
  background-color: var(--navy);
  transition: width 0.25s ease;
}

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

.nav-aside {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.nav-social {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.nav-social a {
  color: var(--text-muted);
  font-size: 1.1rem;
}

.nav-social a:hover {
  color: var(--navy);
}

.mobile-menu-btn {
  display: none;
  font-size: 1.35rem;
  cursor: pointer;
  color: var(--navy);
  padding: 0.25rem;
}

/* Hero */
#hero {
  min-height: 88vh;
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  overflow: hidden;
  padding: 96px 0 64px;
}

.hero-backdrop {
  position: absolute;
  inset: 0;
  z-index: 0;
  background: var(--page-muted) center / cover no-repeat;
  background-image: url('../images/Home.jpg');
}

.hero-overlay {
  position: absolute;
  inset: 0;
  z-index: 1;
  background: var(--hero-overlay);
}

.hero-content {
  position: relative;
  z-index: 2;
  text-align: center;
  max-width: 820px;
  padding: 32px 20px;
}

.hero-name {
  font-size: clamp(2.2rem, 5vw, 3.35rem);
  font-weight: 700;
  margin-bottom: 0.5rem;
  letter-spacing: 0.02em;
  line-height: 1.15;
  color: #fff;
  text-shadow: 0 2px 24px rgba(0, 0, 0, 0.35);
}

.hero-title {
  font-size: clamp(1.05rem, 2.2vw, 1.35rem);
  color: rgba(255, 255, 255, 0.92);
  margin-bottom: 1rem;
  font-weight: 500;
  font-family: 'Source Serif 4', Georgia, serif;
  text-shadow: 0 1px 12px rgba(0, 0, 0, 0.3);
}

.hero-subtitle {
  font-family: 'Source Serif 4', Georgia, serif;
  font-style: italic;
  color: rgba(255, 255, 255, 0.85);
  font-size: 1.05rem;
  margin-bottom: 1.75rem;
  min-height: 1.6em;
}

.hero-tagline {
  font-size: 1.05rem;
  color: rgba(255, 255, 255, 0.88);
  max-width: 640px;
  margin: 0 auto 2rem;
  line-height: 1.6;
  text-shadow: 0 1px 10px rgba(0, 0, 0, 0.25);
}

.btn-cta {
  padding: 14px 32px;
  background: var(--navy);
  border: 2px solid var(--navy);
  color: #fff;
  border-radius: 999px;
  font-weight: 600;
  font-size: 0.95rem;
  font-family: 'Source Serif 4', Georgia, serif;
  display: inline-block;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.2);
}

.btn-cta:hover {
  background: var(--navy-hover);
  border-color: var(--navy-hover);
  color: #fff;
}

/* Sections */
section {
  padding: 88px 0;
}

section:nth-of-type(even) {
  background: var(--page-muted);
}

/* About */
.about-layout {
  display: grid;
  grid-template-columns: minmax(200px, 280px) 1fr;
  gap: 2.5rem;
  align-items: start;
  max-width: 960px;
  margin: 0 auto;
}

.about-portrait {
  position: relative;
}

.about-profile-img {
  width: 100%;
  max-width: 260px;
  aspect-ratio: 1;
  object-fit: cover;
  border-radius: 12px;
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
  display: block;
  margin: 0 auto;
}

.about-card {
  border-left: 4px solid var(--navy);
}

.about-text {
  font-size: 1.05rem;
  color: var(--text);
}

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

.timeline::after {
  content: '';
  position: absolute;
  width: 2px;
  background-color: var(--border);
  top: 0;
  bottom: 0;
  left: 50px;
}

.timeline-item {
  position: relative;
  margin-bottom: 48px;
  padding-left: 80px;
  opacity: 0;
  transform: translateX(-16px);
  transition: 0.45s ease;
}

.timeline-item.visible {
  opacity: 1;
  transform: translateX(0);
}

.timeline-dot {
  position: absolute;
  left: 41px;
  top: 6px;
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background: var(--navy);
  border: 4px solid var(--page);
  box-shadow: 0 0 0 2px var(--navy);
  z-index: 10;
}

section:nth-of-type(even) .timeline-dot {
  border-color: var(--page-muted);
}

.timeline-date {
  color: var(--navy);
  font-weight: 600;
  margin-bottom: 0.5rem;
  font-size: 0.88rem;
  font-family: 'Source Serif 4', Georgia, serif;
}

.timeline-content h3 {
  font-size: 1.3rem;
  margin-bottom: 0.4rem;
  color: var(--text);
}

.timeline-content h4 {
  font-size: 1.02rem;
  color: var(--text-muted);
  margin-bottom: 0.5rem;
  font-weight: 400;
}

.gpa-badge {
  display: inline-block;
  background: var(--accent-soft);
  color: var(--navy);
  padding: 4px 10px;
  border-radius: 4px;
  font-size: 0.82rem;
  font-weight: 600;
  font-family: 'Source Serif 4', Georgia, serif;
}

.gpa-badge + .gpa-badge {
  margin-left: 0.5rem;
}

.dissertation {
  margin-top: 1rem;
  padding: 1rem;
  background: var(--page-muted);
  border-radius: 8px;
  border-left: 3px solid var(--navy);
  font-size: 0.95rem;
  color: var(--text-muted);
  font-style: italic;
}

/* Skills */
.skills-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.75rem;
}

.skill-category h3 {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 1.25rem;
  color: var(--navy);
  font-size: 1.15rem;
}

.skill-bar-container {
  margin-bottom: 1.25rem;
}

.skill-info {
  display: flex;
  justify-content: space-between;
  margin-bottom: 0.4rem;
  font-size: 0.88rem;
  color: var(--text-muted);
}

.progress-bg {
  width: 100%;
  height: 8px;
  background: var(--accent-soft);
  border-radius: 4px;
  overflow: hidden;
}

.progress-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--navy), #2a3f66);
  width: 0;
  border-radius: 4px;
  transition: width 1.4s ease-out;
}

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

.skill-tag {
  font-size: 0.78rem;
  padding: 4px 11px;
  background: var(--page-muted);
  border-radius: 999px;
  color: var(--text-muted);
  border: 1px solid var(--border);
  font-family: 'Source Serif 4', Georgia, serif;
}

/* Publications */
.pub-card {
  border-left: 4px solid var(--navy);
  margin-bottom: 1.25rem;
  position: relative;
  overflow: hidden;
}

.pub-card--line-accent {
  border-left-color: #2a4a7a;
}

.pub-status {
  position: absolute;
  top: 18px;
  right: 18px;
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  padding: 5px 10px;
  border-radius: 4px;
  background: var(--accent-soft);
  color: var(--navy);
  border: 1px solid var(--border);
  font-family: 'Source Serif 4', Georgia, serif;
  font-weight: 600;
}

.pub-status--published {
  color: #fff;
  background: var(--published);
  border-color: var(--published);
}

.pub-title {
  font-size: 1.12rem;
  font-weight: 600;
  margin-bottom: 0.45rem;
  padding-right: 120px;
  color: var(--text);
  font-family: 'Playfair Display', Georgia, serif;
}

.pub-meta {
  color: var(--text-muted);
  font-size: 0.9rem;
  margin-bottom: 0.35rem;
}

.pub-card a {
  color: #1a4b8c;
  word-break: break-all;
}

.pub-card a:hover {
  text-decoration: underline;
}

.subheading-muted {
  margin-top: 2.75rem;
  margin-bottom: 1.35rem;
  text-align: center;
  color: var(--text-muted);
  font-family: 'Playfair Display', Georgia, serif;
  font-size: 1.25rem;
  font-weight: 600;
}

.poster-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.25rem;
  margin-top: 0.5rem;
}

.poster-card {
  border-top: 3px solid var(--navy);
}

.poster-label {
  color: var(--navy);
  font-weight: 700;
  font-size: 0.88rem;
  margin-bottom: 0.45rem;
  font-family: 'Source Serif 4', Georgia, serif;
}

.poster-title {
  font-size: 0.98rem;
  line-height: 1.45;
  color: var(--text);
}

.poster-card a {
  display: inline-block;
  margin-top: 0.65rem;
  color: #1a4b8c;
  font-size: 0.85rem;
}

.poster-card a:hover {
  text-decoration: underline;
}

/* Projects */
.projects-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.75rem;
}

.project-card {
  display: flex;
  flex-direction: column;
  height: 100%;
  border: 1px solid var(--border);
}

.project-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  margin-bottom: 0.85rem;
}

.folder-icon {
  font-size: 1.75rem;
  color: var(--navy);
}

.project-links a {
  font-size: 1.15rem;
  color: var(--text-muted);
  margin-left: 10px;
}

.project-links a:hover {
  color: var(--navy);
}

.project-title {
  font-size: 1.2rem;
  margin-bottom: 0.65rem;
  color: var(--text);
}

.project-desc {
  font-size: 0.95rem;
  color: var(--text-muted);
  margin-bottom: 1.25rem;
  flex-grow: 1;
}

.project-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  font-size: 0.82rem;
  color: var(--navy);
  font-family: 'Source Serif 4', Georgia, serif;
}

/* Leadership */
.leadership-panel {
  max-width: 800px;
  margin: 0 auto;
}

.leadership-card {
  display: flex;
  align-items: center;
  gap: 1.25rem;
  margin-bottom: 1.25rem;
}

.leadership-icon {
  min-width: 48px;
  height: 48px;
  background: var(--accent-soft);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--navy);
  font-size: 1.1rem;
  border: 1px solid var(--border);
}

.leader-title {
  color: var(--text);
  font-size: 1.05rem;
  font-family: 'Playfair Display', Georgia, serif;
  font-weight: 600;
}

.leader-meta {
  color: var(--navy);
  font-size: 0.88rem;
  margin-top: 0.2rem;
  font-family: 'Source Serif 4', Georgia, serif;
}

/* Footer / contact */
#contact {
  background-color: var(--navy);
  padding: 80px 0 40px;
  text-align: center;
  color: rgba(255, 255, 255, 0.9);
}

#contact .section-title {
  background: none;
  -webkit-text-fill-color: #fff;
  color: #fff;
}

#contact .section-title::after {
  background: rgba(255, 255, 255, 0.45);
}

.contact-grid {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 2.25rem 3rem;
  margin-bottom: 3rem;
}

.contact-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.75rem;
}

.contact-icon {
  width: 56px;
  height: 56px;
  background: rgba(255, 255, 255, 0.08);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.35rem;
  color: #fff;
  border: 1px solid rgba(255, 255, 255, 0.2);
  transition: 0.25s ease;
}

.contact-item:hover .contact-icon {
  background: #fff;
  color: var(--navy);
  transform: scale(1.06);
}

.contact-text {
  color: rgba(255, 255, 255, 0.75);
  font-size: 0.92rem;
  max-width: 260px;
  text-align: center;
  word-break: break-word;
}

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.15);
  padding-top: 1.75rem;
  color: rgba(255, 255, 255, 0.55);
  font-size: 0.88rem;
}

/* Back to top */
#scrollTop {
  position: fixed;
  bottom: 28px;
  right: 28px;
  width: 48px;
  height: 48px;
  background: var(--navy);
  color: #fff;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.3s ease, transform 0.25s ease;
  z-index: 999;
  box-shadow: 0 6px 24px rgba(20, 27, 45, 0.35);
  font-size: 1.1rem;
  border: 1px solid rgba(255, 255, 255, 0.12);
}

#scrollTop.active {
  opacity: 1;
  pointer-events: auto;
}

#scrollTop:hover {
  transform: translateY(-4px);
  background: var(--navy-hover);
}

#scrollTop:focus-visible {
  outline: 2px solid #fff;
  outline-offset: 3px;
}

/* Experience */
.experience-list {
  max-width: 900px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 1.35rem;
}

.exp-card h3 {
  font-size: 1.2rem;
  margin-bottom: 0.3rem;
  color: var(--text);
}

.exp-card .exp-org {
  color: var(--navy);
  font-weight: 600;
  font-size: 0.92rem;
  margin-bottom: 0.4rem;
  font-family: 'Source Serif 4', Georgia, serif;
}

.exp-card .exp-dates {
  color: var(--text-muted);
  font-size: 0.84rem;
  margin-bottom: 0.85rem;
}

.exp-card ul {
  margin: 0;
  padding-left: 1.2rem;
  color: var(--text);
  font-size: 0.96rem;
  line-height: 1.6;
}

.exp-card li {
  margin-bottom: 0.45rem;
}

.project-thumb {
  width: 100%;
  height: 140px;
  object-fit: cover;
  border-radius: 10px;
  margin-bottom: 0.85rem;
  background: var(--page-muted);
  border: 1px solid var(--border);
}

.project-thumb[hidden] {
  display: none;
}

@keyframes fadeUp {
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* Mobile */
@media (max-width: 900px) {
  .about-layout {
    grid-template-columns: 1fr;
    text-align: center;
  }

  .about-card {
    text-align: left;
  }
}

@media (max-width: 768px) {
  .nav-inner {
    display: flex;
    flex-wrap: wrap;
    justify-content: space-between;
    align-items: center;
  }

  .nav-inner .logo,
  .nav-inner .nav-links,
  .nav-inner .nav-aside {
    justify-self: unset;
  }

  .nav-inner .logo {
    order: 1;
  }

  .nav-inner .nav-aside {
    order: 2;
  }

  .nav-links {
    order: 3;
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    width: 100%;
    background: #fff;
    flex-direction: column;
    padding: 1.25rem;
    text-align: center;
    border-bottom: 1px solid var(--border);
    gap: 1rem;
    box-shadow: var(--shadow);
  }

  .nav-links.active {
    display: flex;
  }

  .mobile-menu-btn {
    display: block;
  }

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

  .timeline::after {
    left: 20px;
  }

  .timeline-item {
    padding-left: 50px;
  }

  .timeline-dot {
    left: 11px;
  }

  .pub-title {
    padding-right: 0;
  }

  .pub-status {
    position: static;
    display: inline-block;
    margin-bottom: 0.65rem;
  }
}