@import url("https://fonts.googleapis.com/css2?family=Be+Vietnam+Pro:wght@300;400;500;600;700;800&family=JetBrains+Mono:wght@400;500;700&display=swap");

/* ===== BASE STYLES ===== */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --bg-primary: #0b0905;
  --bg-secondary: #14100a;
  --text-primary: #f7f0e2;
  --text-secondary: #b9a784;
  --text-muted: #8a7c60;
  --accent: #f5a623;
  --accent-hover: #ffc24b;
  --accent-soft: #ffd97d;
  --accent-deep: #b9750a;
  --gradient: linear-gradient(
    118deg,
    #ffe09a 0%,
    #ffc24b 38%,
    #f5a623 64%,
    #e07b00 100%
  );
  --glass-bg: rgba(255, 182, 62, 0.045);
  --glass-border: rgba(245, 166, 35, 0.18);
  --shadow: 0 0 40px rgba(245, 166, 35, 0.18);
  --line: rgba(245, 166, 35, 0.16);
  --nav-bg: rgba(11, 9, 5, 0.85);
  --grid-line: rgba(245, 166, 35, 0.05);
}

[data-theme="light"] {
  --bg-primary: #f8f9fb;
  --bg-secondary: #eef0f5;
  --text-primary: #1a1f3a;
  --text-secondary: #4a5568;
  --text-muted: #8896b0;
  --accent: #d4920a;
  --accent-hover: #b8780a;
  --accent-soft: #e8a80e;
  --accent-deep: #8a5c06;
  --gradient: linear-gradient(118deg, #e8a80e 0%, #d4920a 38%, #b8780a 64%, #8a5c06 100%);
  --glass-bg: rgba(26, 31, 58, 0.04);
  --glass-border: rgba(100, 120, 180, 0.15);
  --shadow: 0 0 40px rgba(212, 146, 10, 0.15);
  --nav-bg: rgba(248, 249, 251, 0.92);
  --grid-line: rgba(100, 120, 180, 0.1);
}

body {
  font-family: "Be Vietnam Pro", system-ui, sans-serif;
  background: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

html {
  scroll-behavior: smooth;
}

/* ===== AMBIENT BACKGROUND ===== */
body::before {
  content: "";
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background:
    radial-gradient(
      1200px 700px at 78% -8%,
      rgba(255, 170, 40, 0.18),
      transparent 60%
    ),
    radial-gradient(
      900px 600px at 10% 110%,
      rgba(185, 117, 10, 0.12),
      transparent 60%
    ),
    linear-gradient(160deg, #0b0905 0%, #100c06 50%, #0a0804 100%);
  z-index: -2;
  pointer-events: none;
}

body::after {
  content: "";
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-image:
    linear-gradient(var(--grid-line) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid-line) 1px, transparent 1px);
  background-size: 54px 54px;
  z-index: -1;
  pointer-events: none;
  opacity: 0.7;
}

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

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* ===== NAVIGATION ===== */
nav {
  position: fixed;
  top: 0;
  width: 100%;
  background: var(--nav-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--glass-border);
  z-index: 1000;
  padding: 1rem 0;
}

.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 2rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

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

.nav-links {
  display: flex;
  gap: 2rem;
  list-style: none;
}

.nav-links a {
  color: var(--text-secondary);
  text-decoration: none;
  font-weight: 500;
  font-size: 0.9rem;
  letter-spacing: 0.02em;
  transition: color 0.3s ease;
  position: relative;
}

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

.nav-links a::after {
  content: "";
  position: absolute;
  bottom: -5px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--gradient);
  transition: width 0.3s ease;
}

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

.theme-toggle {
  background: var(--glass-bg);
  border: 1px solid var(--glass-border);
  padding: 0.5rem 1rem;
  border-radius: 50px;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 0.5rem;
  color: var(--text-primary);
  transition: all 0.3s ease;
}

.theme-toggle:hover {
  background: var(--accent);
  color: var(--bg-primary);
  border-color: var(--accent);
}

.mobile-menu-btn {
  display: none;
  background: none;
  border: none;
  font-size: 1.5rem;
  cursor: pointer;
  color: var(--text-primary);
}

/* ===== CONTAINER ===== */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 6rem 2rem 2rem;
}

/* ===== HERO SECTION ===== */
.hero {
  min-height: 90vh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  position: relative;
  padding-top: 80px;
}

.hero-content {
  background: var(--glass-bg);
  border-radius: 30px;
  border: 1px solid var(--glass-border);
  padding: 3rem 3.5rem;
  box-shadow: 0 0 60px rgba(245, 166, 35, 0.12);
  max-width: 900px;
  width: 100%;
  animation: fadeInUp 1s ease;
  display: flex;
  align-items: center;
  gap: 3rem;
}

.hero-left {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: flex-start;
}

.hero-right {
  flex-shrink: 0;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: "JetBrains Mono", monospace;
  font-size: 0.75rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--accent-hover);
  border: 1px solid var(--glass-border);
  padding: 8px 16px;
  border-radius: 99px;
  background: rgba(245, 166, 35, 0.06);
  margin-bottom: 1.5rem;
}

.profile-image {
  width: 240px;
  height: 240px;
  border-radius: 50%;
  border: 3px solid var(--glass-border);
  box-shadow: 0 0 40px rgba(245, 166, 35, 0.25);
  object-fit: cover;
  display: block;
}

.hero h1 {
  font-size: clamp(2.8rem, 5vw, 4.5rem);
  font-weight: 800;
  margin-bottom: 1rem;
  letter-spacing: -0.02em;
  line-height: 1.05;
  text-align: left;
}

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

.name-white {
  -webkit-text-fill-color: var(--text-primary);
}

.hero .subtitle {
  font-size: 1.5rem;
  color: var(--text-secondary);
  margin-bottom: 1rem;
}

.hero .description {
  color: var(--text-secondary);
  max-width: 480px;
  margin: 0 0 2rem;
  line-height: 1.8;
  font-style: italic;
  text-align: left;
}

.social-links {
  display: flex;
  gap: 1rem;
  justify-content: flex-start;
  margin-top: 0;
  flex-wrap: wrap;
}

.social-link {
  background: rgba(245, 166, 35, 0.06);
  border: 1px solid var(--glass-border);
  padding: 0.75rem 1.5rem;
  border-radius: 50px;
  text-decoration: none;
  color: var(--accent-hover);
  font-family: "JetBrains Mono", monospace;
  font-size: 0.85rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
  transition: all 0.3s ease;
}

.social-link:hover {
  transform: translateY(-3px);
  background: var(--accent);
  color: var(--bg-primary);
  border-color: var(--accent);
  box-shadow: 0 0 20px rgba(245, 166, 35, 0.4);
}

/* ===== SECTIONS ===== */
section {
  margin-bottom: 4rem;
}

.section-title {
  font-size: 2.5rem;
  font-weight: 800;
  margin-bottom: 0.5rem;
  text-align: center;
  background: var(--gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  letter-spacing: -0.02em;
}

.section-subtitle {
  text-align: center;
  font-family: "JetBrains Mono", monospace;
  font-size: 1rem;
  letter-spacing: 0.1em;
  color: var(--text-muted);
  margin-top: -1em;
  margin-bottom: 0;
}

.section-subtitle::after,
.section-title::after {
  content: "";
  display: block;
  height: 3px;
  width: 74px;
  border-radius: 3px;
  background: var(--gradient);
  margin: 14px auto 26px;
  box-shadow: var(--shadow);
}

.section-subtitle::after {
  margin-top: 14px;
}

.section-title:has(+ .section-subtitle)::after {
  display: none;
}

/* ===== GLASS CARDS ===== */
.glass-card {
  background: linear-gradient(
    180deg,
    rgba(255, 182, 62, 0.055),
    rgba(255, 182, 62, 0.012)
  );
  border-radius: 16px;
  border: 1px solid var(--glass-border);
  padding: 2rem;
  margin-bottom: 1.5rem;
  transition: all 0.3s ease;
  position: relative;
}

.glass-card:hover {
  transform: translateY(-4px);
  border-color: rgba(245, 166, 35, 0.45);
  box-shadow: 0 0 30px rgba(245, 166, 35, 0.12);
}

/* ===== EDUCATION STATS ===== */
.education-stats {
  display: flex;
  justify-content: space-around;
  margin-top: 2rem;
  flex-wrap: wrap;
  gap: 1rem;
}

.stat-item {
  text-align: center;
  border: 1px solid var(--glass-border);
  border-radius: 16px;
  padding: 1.25rem 1.5rem;
  background: rgba(245, 166, 35, 0.04);
  flex: 1;
  min-width: 120px;
}

.stat-number {
  font-size: 2.5rem;
  font-weight: 800;
  background: var(--gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  line-height: 1;
}

.stat-label {
  color: var(--text-secondary);
  font-size: 0.8rem;
  font-family: "JetBrains Mono", monospace;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  margin-top: 6px;
}

/* ===== PUBLICATIONS ===== */
.publication-item {
  margin-bottom: 1.5rem;
  padding-bottom: 1.5rem;
  border-bottom: 1px solid rgba(245, 166, 35, 0.09);
  text-align: justify;
}

.publication-item:last-child {
  border-bottom: none;
  margin-bottom: 0;
  padding-bottom: 0;
}

.publication-item h4 {
  color: var(--text-primary);
  margin-bottom: 0.5rem;
  line-height: 1.6;
  font-size: 0.95rem;
}

.publication-meta {
  color: var(--text-secondary);
  font-size: 0.85rem;
  font-style: italic;
  line-height: 1.6;
}

.doi-link {
  color: var(--accent-hover);
  text-decoration: none;
  font-weight: 500;
}

.doi-link:hover {
  text-decoration: underline;
}

.paper-title-link {
  color: var(--text-primary);
  text-decoration: none;
  transition: all 0.3s ease;
  position: relative;
  display: inline;
}

.paper-title-link i {
  margin-left: 0.4em;
  font-size: 0.9em;
  opacity: 0;
  transform: translateX(-5px);
  transition: all 0.3s ease;
  color: var(--accent);
}

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

.paper-title-link:hover i {
  opacity: 1;
  transform: translateX(0);
}

/* ===== TIMELINE ===== */
.timeline {
  position: relative;
  padding-left: 2rem;
}

.timeline::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  height: 100%;
  width: 2px;
  background: linear-gradient(
    180deg,
    var(--accent-deep),
    var(--accent-hover),
    var(--accent-deep)
  );
}

.timeline-item {
  position: relative;
  margin-bottom: 2rem;
  padding-left: 2rem;
}

.timeline-item::before {
  content: "";
  position: absolute;
  left: -1.9rem;
  top: 0.35rem;
  transform: translateX(-50%);
  width: 11px;
  height: 11px;
  border-radius: 50%;
  background: var(--gradient);
  box-shadow: 0 0 10px var(--accent);
}

.timeline-item h3 {
  color: var(--text-primary);
  font-weight: 700;
  margin-bottom: 0.5rem;
}

.timeline-item p {
  text-align: justify;
}

.timeline-date {
  font-family: "JetBrains Mono", monospace;
  font-size: 0.8rem;
  letter-spacing: 0.06em;
  color: var(--accent-hover);
  font-weight: 600;
  margin-bottom: 0.5rem;
}

.timeline-content {
  color: var(--text-secondary);
  font-size: 0.9rem;
  line-height: 1.65;
}

/* ===== SKILLS GRID ===== */
.skills-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 1.5rem;
}

.skill-category h3 {
  font-family: "JetBrains Mono", monospace;
  font-size: 0.8rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--accent-hover);
  margin-bottom: 1rem;
}

.skill-list {
  list-style: none;
}

.skill-list li {
  padding: 0.5rem 0;
  border-top: 1px solid rgba(245, 166, 35, 0.08);
  color: var(--text-secondary);
  position: relative;
  padding-left: 1.5rem;
  font-size: 0.9rem;
}

.skill-list li:first-child {
  border-top: none;
}

.skill-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 50%;
  transform: translateY(-50%);
  width: 7px;
  height: 7px;
  border-radius: 2px;
  background: var(--gradient);
}

/* ===== AWARDS GRID ===== */
.awards-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 1.5rem;
}

.award-item {
  display: flex;
  gap: 1rem;
  align-items: start;
  border: 1px solid rgba(245, 166, 35, 0.1);
  border-radius: 12px;
  padding: 1rem;
  background: rgba(245, 166, 35, 0.03);
  transition: border-color 0.3s ease;
}

.award-item:hover {
  border-color: rgba(245, 166, 35, 0.3);
}

.award-icon {
  font-size: 1.5rem;
  flex-shrink: 0;
  color: var(--accent);
}

.award-info h4 {
  color: var(--text-primary);
  font-size: 0.9rem;
  margin-bottom: 0.25rem;
}

.award-info p {
  font-size: 0.85rem;
}

.award-date {
  font-family: "JetBrains Mono", monospace;
  font-size: 0.75rem;
  letter-spacing: 0.06em;
  color: var(--accent-hover);
  font-weight: 600;
  margin-bottom: 0.25rem;
}

/* ===== CONTACT ===== */
.contact-info {
  text-align: center;
  font-size: 1.2rem;
}

.contact-info a {
  color: var(--accent-hover);
  text-decoration: none;
  font-weight: 600;
  font-family: "JetBrains Mono", monospace;
}

.contact-info a:hover {
  color: var(--accent-soft);
  text-decoration: underline;
}

/* ===== FOOTER ===== */
footer {
  text-align: center;
  padding: 2rem;
  color: var(--text-muted);
  border-top: 1px solid var(--glass-border);
  font-family: "JetBrains Mono", monospace;
  font-size: 0.8rem;
  letter-spacing: 0.1em;
}

/* ===== RESPONSIVE ===== */
@media (max-width: 768px) {
  .nav-links {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--nav-bg);
    backdrop-filter: blur(12px);
    flex-direction: column;
    padding: 1rem;
    border-bottom: 1px solid var(--glass-border);
  }

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

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

  .hero-content {
    flex-direction: column-reverse;
    align-items: center;
    padding: 2rem;
    gap: 1.5rem;
  }

  .hero-left {
    align-items: center;
    text-align: center;
  }

  .hero h1 {
    font-size: 2.4rem;
    text-align: center;
  }

  .hero .description {
    text-align: center;
    margin: 0 auto 1.5rem;
  }

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

  .hero {
    padding-top: 100px;
  }

  .hero .subtitle {
    font-size: 1.2rem;
  }

  .profile-image {
    width: 180px;
    height: 180px;
  }

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

  .social-links {
    flex-direction: column;
  }

  .container {
    padding: 5rem 1rem 1rem;
  }

  .hero-content {
    padding: 2rem;
  }
}

/* ===== THEME TOGGLE — hidden since site is dark-only ===== */
.theme-toggle {
  display: none;
}

/* ===== EXPERIENCE TABS ===== */
.experience-tabs {
  display: flex;
  justify-content: center;
  gap: 1rem;
  margin-bottom: 2rem;
  flex-wrap: wrap;
}

.tab-btn {
  background: rgba(245, 166, 35, 0.05);
  border: 1px solid var(--glass-border);
  padding: 0.75rem 1.5rem;
  border-radius: 50px;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 0.5rem;
  color: var(--text-secondary);
  font-family: "Be Vietnam Pro", sans-serif;
  font-size: 0.9rem;
  font-weight: 500;
  transition: all 0.3s ease;
}

.tab-btn i {
  font-size: 1rem;
}

.tab-btn:hover {
  transform: translateY(-2px);
  border-color: rgba(245, 166, 35, 0.4);
  color: var(--accent-hover);
}

.tab-btn.active {
  background: var(--gradient);
  color: var(--bg-primary);
  border-color: transparent;
  font-weight: 600;
  box-shadow: 0 0 20px rgba(245, 166, 35, 0.3);
}

.tab-content {
  display: none;
}

.tab-content.active {
  display: block;
  animation: fadeInUp 0.5s ease;
}

/* ===== CERTIFICATION LINK STYLE ===== */
.cert-link {
  color: var(--text-primary);
  text-decoration: none;
  transition: all 0.3s ease;
  position: relative;
  display: inline-block;
  font-size: 0.95rem;
}

.cert-link i {
  margin-left: 0.4em;
  font-size: 0.9em;
  opacity: 0;
  transform: translateX(-5px);
  transition: all 0.3s ease;
  color: var(--accent);
}

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

.cert-link:hover i {
  opacity: 1;
  transform: translateX(0);
}

/* ===== GLASS CARD HEADINGS ===== */
.glass-card h3 {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--text-primary);
}

.glass-card > h3:first-child,
.glass-card > p:first-child {
  color: var(--text-primary);
}

/* ===== SECTION HEADING KICKER ===== */
.section-kicker {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: "JetBrains Mono", monospace;
  font-size: 0.75rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--accent-hover);
  margin-bottom: 0.5rem;
}

.section-kicker .dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 10px var(--accent);
}

/* ===== VIEW ALL BUTTON ===== */
.view-all-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-top: 1.5rem;
  margin-left: auto;
  margin-right: 0;
  padding: 10px 20px;
  border: 1px solid var(--glass-border);
  border-radius: 99px;
  background: rgba(245, 166, 35, 0.06);
  color: var(--accent-hover);
  font-family: "JetBrains Mono", monospace;
  font-size: 0.8rem;
  letter-spacing: 0.04em;
  text-decoration: none;
  transition: all 0.3s ease;
}

.view-all-btn:hover {
  background: var(--gradient);
  color: var(--bg-primary);
  border-color: transparent;
  box-shadow: 0 0 20px rgba(245, 166, 35, 0.3);
}

/* ===== PAGE HEADER (subpages) ===== */
.page-header {
  margin-bottom: 2.5rem;
}

.back-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 1.5rem;
  padding: 10px 20px;
  border: 1px solid var(--glass-border);
  border-radius: 99px;
  background: rgba(245, 166, 35, 0.06);
  color: var(--accent-hover);
  font-family: "JetBrains Mono", monospace;
  font-size: 0.8rem;
  letter-spacing: 0.04em;
  text-decoration: none;
  transition: all 0.3s ease;
}

.back-link:hover {
  background: var(--gradient);
  color: var(--bg-primary);
  border-color: transparent;
  box-shadow: 0 0 20px rgba(245, 166, 35, 0.3);
}

/* ===== ACTIVE NAV LINK ===== */
.nav-active {
  color: var(--accent-hover) !important;
}

.nav-active::after {
  width: 100% !important;
}

/* ===== LOGO AS LINK ===== */
a.logo {
  text-decoration: none;
}

/* ===== THEME TOGGLE FIXED BUTTON ===== */
.theme-toggle-fixed {
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  border: 1px solid var(--glass-border);
  background: var(--glass-bg);
  backdrop-filter: blur(12px);
  color: var(--accent-hover);
  font-size: 1.1rem;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 999;
  transition: all 0.3s ease;
  box-shadow: 0 0 20px rgba(245, 166, 35, 0.15);
}

.theme-toggle-fixed:hover {
  background: var(--gradient);
  color: var(--bg-primary);
  border-color: transparent;
  box-shadow: 0 0 24px rgba(245, 166, 35, 0.4);
}

/* ===== LIGHT THEME OVERRIDES ===== */
[data-theme="light"] body::before {
  background:
    radial-gradient(1200px 700px at 78% -8%, rgba(100, 120, 200, 0.07), transparent 60%),
    radial-gradient(900px 600px at 10% 110%, rgba(212, 146, 10, 0.06), transparent 60%),
    linear-gradient(160deg, #f8f9fb 0%, #eef0f5 50%, #f8f9fb 100%);
}

/* ===== SCROLL ANIMATION ===== */
@media (prefers-reduced-motion: reduce) {
  * {
    animation: none !important;
    transition: none !important;
  }
}