/* ========================================================
   Lorenzo L. D. Incardona — Personal Website
   Style: Dark atmospheric aesthetic with grain & particle feel
   ======================================================== */

/* ---------- CUSTOM PROPERTIES ---------- */
:root {
  /* Dark theme (default) */
  --bg-primary:    #0a0a0b;
  --bg-secondary:  #111113;
  --bg-card:       #16161a;
  --bg-card-hover: #1c1c21;
  --bg-elevated:   #1e1e23;

  --text-primary:   #e8e6e3;
  --text-secondary: #94918b;
  --text-muted:     #5a5753;
  --text-accent:    #c4b998;

  --accent:         #c4b998;
  --accent-dim:     #9e9474;
  --accent-glow:    rgba(196, 185, 152, 0.12);

  --border:         rgba(255, 255, 255, 0.06);
  --border-hover:   rgba(255, 255, 255, 0.12);

  --gradient-hero:  linear-gradient(180deg, rgba(10,10,11,0) 0%, rgba(10,10,11,0.35) 50%, rgba(10,10,11,0.75) 100%);

  --font-sans:   'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-serif:  'Playfair Display', Georgia, 'Times New Roman', serif;
  --font-mono:   'JetBrains Mono', 'Fira Code', monospace;

  --space-xs:  0.25rem;
  --space-sm:  0.5rem;
  --space-md:  1rem;
  --space-lg:  1.5rem;
  --space-xl:  2.5rem;
  --space-2xl: 4rem;
  --space-3xl: 6rem;
  --space-4xl: 8rem;

  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-xl: 16px;

  --transition-fast:   150ms ease;
  --transition-base:   300ms ease;
  --transition-slow:   500ms ease;
  --transition-spring: 500ms cubic-bezier(0.34, 1.56, 0.64, 1);

  --header-h: 64px;
}

/* Light theme */
[data-theme="light"] {
  --bg-primary:    #f5f3ef;
  --bg-secondary:  #eae7e1;
  --bg-card:       #ffffff;
  --bg-card-hover: #f9f8f6;
  --bg-elevated:   #ffffff;

  --text-primary:   #1a1917;
  --text-secondary: #5c5952;
  --text-muted:     #9c978e;
  --text-accent:    #7a6f4e;

  --accent:         #7a6f4e;
  --accent-dim:     #9e9474;
  --accent-glow:    rgba(122, 111, 78, 0.08);

  --border:         rgba(0, 0, 0, 0.08);
  --border-hover:   rgba(0, 0, 0, 0.15);

  --gradient-hero:  linear-gradient(180deg, rgba(245,243,239,0) 0%, rgba(245,243,239,0.35) 50%, rgba(245,243,239,0.75) 100%);
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-sans);
  color: var(--text-primary);
  background-color: var(--bg-primary);
  background-image: url('../img/hero-bg.png');
  background-attachment: fixed;
  background-position: center center;
  background-size: cover;
  background-repeat: no-repeat;
  line-height: 1.6;
  overflow-x: hidden;
  transition: background-color var(--transition-slow), color var(--transition-slow);
}

/* Full-page dark scrim over the background image for readability */
body::before {
  content: '';
  position: fixed;
  inset: 0;
  background: rgba(10, 10, 11, 0.72);
  z-index: 0;
  pointer-events: none;
  transition: background var(--transition-slow);
}

[data-theme="light"] body::before {
  background: rgba(245, 243, 239, 0.78);
}

/* Noise / grain overlay — sits on top of everything */
body::after {
  content: '';
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 10000;
  opacity: 0.035;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 256 256' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)' opacity='1'/%3E%3C/svg%3E");
  background-repeat: repeat;
  background-size: 256px 256px;
}

[data-theme="light"] body::after {
  opacity: 0.025;
}

img { display: block; max-width: 100%; height: auto; }
a { color: inherit; text-decoration: none; }
ul { list-style: none; }
button { cursor: pointer; border: none; background: none; font: inherit; color: inherit; }

::selection {
  background: var(--accent);
  color: var(--bg-primary);
}

/* ---------- LAYOUT ---------- */
.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--space-lg);
}

.section {
  padding: var(--space-4xl) 0;
  position: relative;
  z-index: 1;
}

@media (max-width: 768px) {
  .section { padding: var(--space-3xl) 0; }
}

/* ---------- HEADER ---------- */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  height: var(--header-h);
  transition: background var(--transition-base), box-shadow var(--transition-base);
}

.site-header.scrolled {
  background: rgba(10, 10, 11, 0.85);
  backdrop-filter: blur(16px) saturate(180%);
  -webkit-backdrop-filter: blur(16px) saturate(180%);
  box-shadow: 0 1px 0 var(--border);
}

[data-theme="light"] .site-header.scrolled {
  background: rgba(245, 243, 239, 0.85);
}

.header-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--space-lg);
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

/* Logo */
.logo {
  font-family: var(--font-mono);
  font-size: 1.1rem;
  font-weight: 500;
  letter-spacing: 0.15em;
  transition: opacity var(--transition-fast);
}
.logo:hover { opacity: 0.7; }
.logo-accent { color: var(--accent); }

/* Nav */
.nav-list {
  display: flex;
  gap: var(--space-xl);
}

.nav-link {
  font-size: 0.82rem;
  font-weight: 400;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--text-secondary);
  position: relative;
  padding: var(--space-xs) 0;
  transition: color var(--transition-fast);
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: 0;
  width: 0;
  height: 1px;
  background: var(--accent);
  transition: width var(--transition-base);
}

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

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

/* Header actions */
.header-actions {
  display: flex;
  align-items: center;
  gap: var(--space-md);
}

/* Theme toggle */
.theme-toggle {
  width: 36px;
  height: 36px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  transition: background var(--transition-fast);
}
.theme-toggle:hover {
  background: var(--accent-glow);
}

.icon-moon { display: none; }
[data-theme="light"] .icon-sun { display: none; }
[data-theme="light"] .icon-moon { display: block; }

/* Mobile menu toggle */
.menu-toggle {
  display: none;
  width: 36px;
  height: 36px;
  align-items: center;
  justify-content: center;
  position: relative;
}

.hamburger,
.hamburger::before,
.hamburger::after {
  width: 20px;
  height: 1.5px;
  background: var(--text-primary);
  border-radius: 2px;
  transition: all var(--transition-base);
}

.hamburger {
  position: relative;
  display: block;
}
.hamburger::before,
.hamburger::after {
  content: '';
  position: absolute;
  left: 0;
}
.hamburger::before { top: -6px; }
.hamburger::after  { top:  6px; }

.menu-toggle[aria-expanded="true"] .hamburger {
  background: transparent;
}
.menu-toggle[aria-expanded="true"] .hamburger::before {
  top: 0;
  transform: rotate(45deg);
}
.menu-toggle[aria-expanded="true"] .hamburger::after {
  top: 0;
  transform: rotate(-45deg);
}

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

  .main-nav {
    position: fixed;
    top: var(--header-h);
    left: 0;
    right: 0;
    bottom: 0;
    background: var(--bg-primary);
    padding: var(--space-2xl) var(--space-lg);
    transform: translateX(100%);
    transition: transform var(--transition-slow);
    z-index: 999;
  }

  .main-nav.open {
    transform: translateX(0);
  }

  .nav-list {
    flex-direction: column;
    gap: var(--space-lg);
  }

  .nav-link {
    font-size: 1.2rem;
    letter-spacing: 0.08em;
  }
}

/* ---------- HERO ---------- */
.section-hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  padding-top: var(--header-h);
  overflow: hidden;
}

.hero-bg {
  position: absolute;
  inset: 0;
  z-index: 0;
}

#particleCanvas {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
}

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

.hero-content {
  position: relative;
  z-index: 2;
  display: flex;
  flex-direction: column;
  justify-content: center;
  min-height: calc(100vh - var(--header-h));
}

.hero-text {
  max-width: 720px;
}

.hero-label {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: var(--space-lg);
  text-shadow: 0 1px 10px rgba(0, 0, 0, 0.4);
}

.hero-title {
  font-family: var(--font-serif);
  font-size: clamp(2.8rem, 7vw, 5.5rem);
  font-weight: 400;
  line-height: 1.08;
  letter-spacing: -0.02em;
  margin-bottom: var(--space-lg);
  text-shadow: 0 2px 20px rgba(0, 0, 0, 0.5);
}

[data-theme="light"] .hero-title {
  text-shadow: 0 2px 20px rgba(255, 255, 255, 0.6);
}

.hero-title .line {
  display: block;
}

.hero-tagline {
  font-size: 1.15rem;
  color: var(--text-secondary);
  font-style: italic;
  font-family: var(--font-serif);
  margin-bottom: var(--space-2xl);
  text-shadow: 0 1px 10px rgba(0, 0, 0, 0.4);
}

.hero-cta {
  display: flex;
  gap: var(--space-md);
  flex-wrap: wrap;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  padding: 0.75rem 1.75rem;
  font-size: 0.85rem;
  font-weight: 500;
  letter-spacing: 0.04em;
  border-radius: var(--radius-md);
  transition: all var(--transition-base);
}

.btn-primary {
  background: var(--accent);
  color: var(--bg-primary);
}
.btn-primary:hover {
  background: var(--accent-dim);
  transform: translateY(-1px);
  box-shadow: 0 4px 20px var(--accent-glow);
}

.btn-secondary {
  background: rgba(196, 185, 152, 0.15);
  border: 1px solid var(--accent-dim);
  color: var(--accent);
}
.btn-secondary:hover {
  background: rgba(196, 185, 152, 0.28);
  border-color: var(--accent);
  transform: translateY(-1px);
  box-shadow: 0 4px 20px var(--accent-glow);
}

[data-theme="light"] .btn-secondary {
  background: rgba(122, 111, 78, 0.1);
  border-color: var(--accent);
  color: var(--accent);
}
[data-theme="light"] .btn-secondary:hover {
  background: rgba(122, 111, 78, 0.2);
}

.btn-ghost {
  border: 1px solid var(--border-hover);
  color: var(--text-primary);
}
.btn-ghost:hover {
  border-color: var(--accent);
  color: var(--accent);
  transform: translateY(-1px);
}

/* Scroll indicator */
.scroll-indicator {
  position: absolute;
  bottom: var(--space-2xl);
  left: var(--space-lg);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-sm);
}

.scroll-line {
  width: 1px;
  height: 48px;
  background: linear-gradient(180deg, var(--accent) 0%, transparent 100%);
  animation: scrollPulse 2s ease-in-out infinite;
}

@keyframes scrollPulse {
  0%, 100% { opacity: 0.3; transform: scaleY(0.6); }
  50%      { opacity: 1;   transform: scaleY(1); }
}

.scroll-text {
  font-family: var(--font-mono);
  font-size: 0.65rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--text-muted);
}

@media (max-width: 768px) {
  .scroll-indicator { display: none; }
}

/* ---------- SECTION HEADERS ---------- */
.section-header {
  margin-bottom: var(--space-3xl);
}

.section-number {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--accent);
  letter-spacing: 0.15em;
  display: block;
  margin-bottom: var(--space-md);
}

.section-title {
  font-family: var(--font-serif);
  font-size: clamp(2rem, 4vw, 3rem);
  font-weight: 400;
  letter-spacing: -0.01em;
  margin-bottom: var(--space-md);
  text-shadow: 0 1px 12px rgba(0, 0, 0, 0.3);
}

[data-theme="light"] .section-title {
  text-shadow: 0 1px 12px rgba(255, 255, 255, 0.4);
}

.section-subtitle {
  font-size: 1.05rem;
  color: var(--text-secondary);
  max-width: 560px;
  line-height: 1.7;
}

/* ---------- AI LAB CARDS ---------- */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: var(--space-lg);
}

.card {
  background: rgba(22, 22, 26, 0.7);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: var(--space-xl);
  transition: all var(--transition-base);
  position: relative;
  overflow: hidden;
}

[data-theme="light"] .card {
  background: rgba(255, 255, 255, 0.7);
}

.card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--accent-dim), transparent);
  opacity: 0;
  transition: opacity var(--transition-base);
}

.card:hover {
  background: rgba(28, 28, 33, 0.8);
  border-color: var(--border-hover);
  transform: translateY(-2px);
}

[data-theme="light"] .card:hover {
  background: rgba(249, 248, 246, 0.8);
}

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

.card-icon {
  width: 44px;
  height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-md);
  background: var(--accent-glow);
  color: var(--accent);
  margin-bottom: var(--space-lg);
}

.card-title {
  font-family: var(--font-serif);
  font-size: 1.2rem;
  font-weight: 400;
  margin-bottom: var(--space-sm);
}

.card-desc {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.65;
  margin-bottom: var(--space-lg);
}

.card-tag {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--accent-dim);
  padding: 0.25rem 0.6rem;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
}

/* Card as link (AI Lab) */
a.card-link {
  text-decoration: none;
  color: inherit;
  display: flex;
  flex-direction: column;
}

a.card-link:hover .card-link-label {
  color: var(--accent);
  transform: translateX(4px);
}

.card-link-label {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.06em;
  color: var(--text-muted);
  margin-top: auto;
  padding-top: var(--space-lg);
  transition: all var(--transition-fast);
}

/* ---------- TRAINING ---------- */
.section-training {
  background: rgba(17, 17, 19, 0.55);
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
}

[data-theme="light"] .section-training {
  background: rgba(234, 231, 225, 0.55);
}

.training-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: var(--space-lg);
}

.training-card {
  background: rgba(22, 22, 26, 0.7);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: var(--space-xl);
  transition: all var(--transition-base);
}

[data-theme="light"] .training-card {
  background: rgba(255, 255, 255, 0.7);
}

.training-card:hover {
  border-color: var(--border-hover);
  transform: translateY(-2px);
}

.training-type {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: var(--space-md);
}

.training-title {
  font-family: var(--font-serif);
  font-size: 1.2rem;
  font-weight: 400;
  margin-bottom: var(--space-sm);
}

.training-desc {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.65;
  margin-bottom: var(--space-lg);
}

.training-meta {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-sm);
}

.training-meta li {
  font-size: 0.75rem;
  color: var(--text-muted);
  padding: 0.2rem 0.55rem;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
}

/* ---------- WRITINGS ---------- */
.writings-list {
  display: flex;
  flex-direction: column;
}

a.writing-item,
.writing-item {
  display: flex;
  align-items: flex-start;
  gap: var(--space-xl);
  padding: var(--space-xl) 0;
  border-bottom: 1px solid var(--border);
  transition: all var(--transition-base);
  cursor: pointer;
  text-decoration: none;
  color: inherit;
}

.writing-item:first-child {
  border-top: 1px solid var(--border);
}

.writing-item:hover {
  padding-left: var(--space-md);
}

.writing-item:hover .writing-title {
  color: var(--accent);
}

.writing-item:hover .writing-arrow {
  transform: translateX(4px);
  color: var(--accent);
}

.writing-date {
  flex-shrink: 0;
  width: 60px;
}

.writing-year {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--text-muted);
}

.writing-content {
  flex: 1;
  min-width: 0;
}

.writing-title {
  font-family: var(--font-serif);
  font-size: 1.15rem;
  font-weight: 400;
  margin-bottom: var(--space-xs);
  transition: color var(--transition-fast);
}

.writing-excerpt {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.6;
  margin-bottom: var(--space-sm);
}

.writing-tags {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-sm);
}

.writing-tags span {
  font-size: 0.7rem;
  color: var(--text-muted);
  font-family: var(--font-mono);
  letter-spacing: 0.05em;
}

.writing-tags span:not(:last-child)::after {
  content: ' /';
  margin-left: var(--space-sm);
  color: var(--border-hover);
}

.writing-arrow {
  flex-shrink: 0;
  color: var(--text-muted);
  transition: all var(--transition-fast);
  margin-top: 0.2rem;
  display: flex;
  align-items: center;
  gap: 0.4rem;
}

.writing-arrow::after {
  content: 'PDF';
  font-family: var(--font-mono);
  font-size: 0.6rem;
  letter-spacing: 0.08em;
  color: var(--accent-dim);
  opacity: 0;
  transform: translateX(-6px);
  transition: all var(--transition-fast);
}

a.writing-item:hover .writing-arrow::after {
  opacity: 1;
  transform: translateX(0);
}

@media (max-width: 640px) {
  .writing-item {
    flex-direction: column;
    gap: var(--space-sm);
  }
  .writing-arrow { display: none; }
}

/* ---------- SPECIAL CONTENTS ---------- */
.section-special {
  background: rgba(17, 17, 19, 0.55);
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
}

[data-theme="light"] .section-special {
  background: rgba(234, 231, 225, 0.55);
}

.special-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: var(--space-lg);
}

.special-card {
  background: rgba(22, 22, 26, 0.7);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: var(--space-xl);
  transition: all var(--transition-base);
  cursor: pointer;
  position: relative;
  overflow: hidden;
}

[data-theme="light"] .special-card {
  background: rgba(255, 255, 255, 0.7);
}

.special-card:hover {
  border-color: var(--border-hover);
  transform: translateY(-2px);
}

a.special-card {
  text-decoration: none;
  color: inherit;
}

a.special-card:hover .card-link-label {
  color: var(--accent);
  transform: translateX(4px);
}

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

.special-featured {
  grid-column: 1 / -1;
  background: linear-gradient(135deg, rgba(22, 22, 26, 0.75) 0%, rgba(30, 30, 35, 0.8) 100%);
  border-color: var(--border-hover);
}

[data-theme="light"] .special-featured {
  background: linear-gradient(135deg, rgba(255, 255, 255, 0.75) 0%, rgba(255, 255, 255, 0.85) 100%);
}

@media (min-width: 640px) {
  .special-featured {
    padding: var(--space-3xl);
  }
}

.special-badge {
  font-family: var(--font-mono);
  font-size: 0.65rem;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--bg-primary);
  background: var(--accent);
  padding: 0.2rem 0.6rem;
  border-radius: var(--radius-sm);
  display: inline-block;
  margin-bottom: var(--space-lg);
}

.special-title {
  font-family: var(--font-serif);
  font-size: 1.2rem;
  font-weight: 400;
  margin-bottom: var(--space-sm);
}

.special-featured .special-title {
  font-size: 1.6rem;
}

.special-desc {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.65;
  margin-bottom: var(--space-lg);
  max-width: 560px;
}

.special-link {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--text-muted);
  transition: color var(--transition-fast);
}

/* ---------- ABOUT ---------- */
.about-layout {
  display: grid;
  grid-template-columns: 1fr 1.4fr;
  gap: var(--space-3xl);
  align-items: start;
}

@media (max-width: 768px) {
  .about-layout {
    grid-template-columns: 1fr;
    gap: var(--space-2xl);
  }
}

.about-photo-wrapper {
  position: relative;
  border-radius: var(--radius-lg);
  overflow: hidden;
  aspect-ratio: 1 / 1;
}

.about-photo-wrapper img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: grayscale(30%) contrast(1.05);
  transition: filter var(--transition-slow);
}

.about-photo-wrapper:hover img {
  filter: grayscale(0%) contrast(1);
}

.photo-grain {
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 256 256' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.85' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)' opacity='1'/%3E%3C/svg%3E");
  background-repeat: repeat;
  background-size: 128px 128px;
  opacity: 0.06;
  mix-blend-mode: overlay;
}

.about-name {
  font-family: var(--font-serif);
  font-size: 1.5rem;
  font-weight: 400;
  margin-bottom: var(--space-xs);
}

.about-role {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  letter-spacing: 0.08em;
  color: var(--accent);
  margin-bottom: var(--space-xl);
}

.about-bio p {
  font-size: 0.95rem;
  color: var(--text-secondary);
  line-height: 1.75;
  margin-bottom: var(--space-md);
}

.about-bio p:last-child {
  margin-bottom: 0;
}

.about-contact {
  margin-top: var(--space-2xl);
  padding-top: var(--space-xl);
  border-top: 1px solid var(--border);
}

.contact-heading {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text-muted);
  margin-bottom: var(--space-lg);
}

.contact-links {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-md);
}

.contact-link {
  display: inline-flex;
  align-items: center;
  gap: var(--space-sm);
  font-size: 0.85rem;
  color: var(--text-secondary);
  padding: 0.5rem 1rem;
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  transition: all var(--transition-base);
}

.contact-link:hover {
  border-color: var(--accent);
  color: var(--accent);
  background: var(--accent-glow);
}

/* ---------- FOOTER ---------- */
.site-footer {
  padding: var(--space-2xl) 0;
  border-top: 1px solid var(--border);
  position: relative;
  z-index: 1;
  background: rgba(10, 10, 11, 0.6);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
}

[data-theme="light"] .site-footer {
  background: rgba(245, 243, 239, 0.6);
}

.footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: var(--space-lg);
}

.footer-logo {
  font-family: var(--font-mono);
  font-size: 0.9rem;
  font-weight: 500;
  letter-spacing: 0.15em;
  color: var(--text-muted);
}

.footer-copy {
  font-size: 0.78rem;
  color: var(--text-muted);
  margin-top: var(--space-xs);
}

.footer-nav {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-lg);
}

.footer-nav a {
  font-size: 0.8rem;
  color: var(--text-muted);
  transition: color var(--transition-fast);
}

.footer-nav a:hover {
  color: var(--text-primary);
}

.footer-powered {
  text-align: center;
  padding-top: var(--space-lg);
  margin-top: var(--space-lg);
  border-top: 1px solid var(--border);
}

.footer-powered-link {
  color: var(--accent-dim);
  transition: color var(--transition-fast);
}

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

@media (max-width: 640px) {
  .footer-inner {
    flex-direction: column;
    text-align: center;
  }
}

/* ---------- ANIMATIONS ---------- */
[data-animate] {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.7s ease, transform 0.7s ease;
}

[data-animate].visible {
  opacity: 1;
  transform: translateY(0);
}

/* Stagger delay utility */
[data-delay="100"] { transition-delay: 100ms; }
[data-delay="200"] { transition-delay: 200ms; }
[data-delay="300"] { transition-delay: 300ms; }
[data-delay="400"] { transition-delay: 400ms; }

/* Hero specific animations */
.hero-text {
  opacity: 0;
  transform: translateY(30px);
  animation: heroFadeIn 1s ease forwards;
  animation-delay: 0.3s;
}

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

/* ---------- SCROLLBAR ---------- */
::-webkit-scrollbar {
  width: 6px;
}
::-webkit-scrollbar-track {
  background: var(--bg-primary);
}
::-webkit-scrollbar-thumb {
  background: var(--text-muted);
  border-radius: 3px;
}
::-webkit-scrollbar-thumb:hover {
  background: var(--text-secondary);
}

/* ---------- FOCUS STYLES ---------- */
:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

/* ---------- CARD TAGS (multiple) ---------- */
.card-tags {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-sm);
}

/* ---------- TIMELINE (AI Lab) ---------- */
.timeline-section {
  margin-top: var(--space-3xl);
  padding-top: var(--space-2xl);
  border-top: 1px solid var(--border);
}

.timeline-heading {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: var(--space-xl);
}

.timeline {
  position: relative;
  padding-left: var(--space-xl);
}

.timeline::before {
  content: '';
  position: absolute;
  left: 4px;
  top: 6px;
  bottom: 6px;
  width: 1px;
  background: var(--border-hover);
}

.timeline-item {
  position: relative;
  padding-bottom: var(--space-xl);
}

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

.timeline-marker {
  position: absolute;
  left: calc(-1 * var(--space-xl) + 1px);
  top: 6px;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--accent);
  border: 2px solid var(--bg-primary);
}

.timeline-date {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--text-muted);
  letter-spacing: 0.05em;
  margin-bottom: var(--space-xs);
}

.timeline-content h4 {
  font-family: var(--font-serif);
  font-size: 1rem;
  font-weight: 400;
  margin-bottom: var(--space-xs);
}

.timeline-content p {
  font-size: 0.85rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* ---------- TRAINING INSTITUTIONS ---------- */
.training-institutions {
  margin-top: var(--space-3xl);
  padding-top: var(--space-2xl);
  border-top: 1px solid var(--border);
}

.institutions-heading {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: var(--space-lg);
}

.institutions-list {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-md);
  margin-bottom: var(--space-2xl);
}

.institution {
  font-size: 0.9rem;
  color: var(--text-primary);
  padding: 0.5rem 1.1rem;
  border: 1px solid var(--border-hover);
  border-radius: var(--radius-md);
  background: rgba(22, 22, 26, 0.4);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
}

[data-theme="light"] .institution {
  background: rgba(255, 255, 255, 0.4);
}

.past-training {
  padding-top: var(--space-lg);
  border-top: 1px solid var(--border);
}

.past-heading {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-muted);
  margin-bottom: var(--space-sm);
  font-weight: 400;
}

.past-list {
  font-size: 0.88rem;
  color: var(--text-secondary);
  line-height: 1.7;
}

/* ---------- WRITINGS — translation & award ---------- */
.writing-translation {
  font-size: 0.8rem;
  font-style: italic;
  color: var(--accent-dim);
  margin-bottom: var(--space-sm);
  margin-top: var(--space-xs);
}

.writing-award {
  display: block;
  color: var(--accent);
  font-size: 0.9rem;
  margin-top: var(--space-xs);
}

/* ---------- SPECIAL — subsection, venue, translation ---------- */
.special-subsection {
  margin-bottom: var(--space-lg);
}

.special-subsection-title {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  letter-spacing: 0.08em;
  color: var(--accent);
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  margin-bottom: var(--space-sm);
}

.special-translation {
  font-size: 0.82rem;
  font-style: italic;
  color: var(--accent-dim);
  margin-bottom: var(--space-sm);
}

.special-venue {
  display: block;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--text-muted);
  letter-spacing: 0.04em;
  margin-top: auto;
  padding-top: var(--space-md);
  border-top: 1px solid var(--border);
}

.special-card {
  display: flex;
  flex-direction: column;
}

/* ---------- RESEARCH THEMES ---------- */
.research-themes {
  margin-top: var(--space-3xl);
  padding-top: var(--space-2xl);
  border-top: 1px solid var(--border);
}

.themes-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: var(--space-md) var(--space-xl);
  margin-top: var(--space-lg);
}

.theme-item {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  font-size: 0.9rem;
  color: var(--text-secondary);
}

.theme-dot {
  flex-shrink: 0;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--accent);
}

/* ---------- ABOUT — education & skills ---------- */
.about-education {
  margin-top: var(--space-2xl);
  padding-top: var(--space-xl);
  border-top: 1px solid var(--border);
}

.edu-list {
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
}

.edu-item {
  display: flex;
  gap: var(--space-lg);
  align-items: baseline;
}

.edu-year {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--text-muted);
  flex-shrink: 0;
  width: 80px;
  letter-spacing: 0.03em;
}

.edu-detail {
  font-size: 0.88rem;
  color: var(--text-secondary);
  line-height: 1.55;
}

.edu-detail strong {
  color: var(--text-primary);
  font-weight: 500;
}

.edu-detail em {
  color: var(--accent-dim);
  font-style: italic;
}

.about-skills {
  margin-top: var(--space-2xl);
  padding-top: var(--space-xl);
  border-top: 1px solid var(--border);
}

.skills-list {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-sm);
}

.skill-tag {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.06em;
  color: var(--accent);
  padding: 0.3rem 0.7rem;
  border: 1px solid var(--border-hover);
  border-radius: var(--radius-sm);
  background: var(--accent-glow);
}

@media (max-width: 480px) {
  .edu-item {
    flex-direction: column;
    gap: var(--space-xs);
  }
  .edu-year { width: auto; }

  .timeline { padding-left: var(--space-lg); }
  .timeline-marker {
    left: calc(-1 * var(--space-lg) + 1px);
  }
}

/* ---------- PRINT ---------- */
@media print {
  .site-header,
  .scroll-indicator,
  .theme-toggle,
  .hero-bg,
  #particleCanvas { display: none !important; }

  body { background: #fff; color: #000; }
  body::after { display: none; }
  .section { padding: 2rem 0; }
}