/* ============================================================
   THEME TOKENS — 个人网站统一设计语言
   Tailwind utilities via CDN (cdn.tailwindcss.com)
   ============================================================ */

/* ========== LIGHT MODE (default) ========== */
:root {
  /* Font families */
  --font-sans: 'Plus Jakarta Sans', 'Noto Sans SC', system-ui, sans-serif;
  --font-display: 'Space Grotesk', 'Noto Sans SC', system-ui, sans-serif;

  /* Type scale — matched to original design tokens */
  --text-eyebrow: 0.625rem;
  --text-caption: 0.75rem;
  --text-tag: 0.75rem;
  --text-body-sm: 0.8125rem;
  --text-body: 0.875rem;
  --text-body-lg: 1rem;
  --text-h4: 1.125rem;
  --text-h3: 1.25rem;
  --text-h2: 1.5rem;
  --text-h1: 2rem;

  /* Radius scale */
  --radius-sm: 0.5rem;
  --radius-md: 0.75rem;
  --radius-lg: 1rem;
  --radius-xl: 1.5rem;
  --radius-2xl: 2rem;

  /* Spacing */
  --spacing-section-py: 6rem;
  --spacing-container-narrow: 48rem;
  --spacing-container-normal: 64rem;
  --spacing-container-wide: 72rem;

  /* Colors — Light mode */
  --color-glass-bg: rgba(255,255,255,0.55);
  --color-glass-bg-strong: rgba(255,255,255,0.78);
  --color-glass-bg-subtle: rgba(255,255,255,0.35);
  --color-glass-border: rgba(0,0,0,0.06);
  --color-glass-border-light: rgba(255,255,255,0.1);
  --color-text-primary: #0f172a;
  --color-text-secondary: #475569;
  --color-text-tertiary: #94a3b8;
  --color-bg-page: #fafbfc;
  --color-bg-page-alt: #f2f4f8;
  --color-divider: rgba(0,0,0,0.08);
  --color-accent: #6366f1;
  --color-accent-glow: rgba(99,102,241,0.18);
  --color-accent-color: #6366f1;
  --color-card-outer-bg: rgba(0,0,0,0.02);
  --color-card-outer-ring: rgba(0,0,0,0.05);
  --color-card-inner-bg: #ffffff;
  --color-card-shadow: 0 1px 3px rgba(0,0,0,0.03), 0 8px 48px rgba(0,0,0,0.04), 0 2px 12px rgba(0,0,0,0.02);
  --color-card-shadow-hover: 0 2px 4px rgba(0,0,0,0.04), 0 12px 64px rgba(0,0,0,0.06), 0 4px 20px rgba(99,102,241,0.06);
  --color-nav-bg: rgba(255,255,255,0.8);
  --color-nav-border: rgba(0,0,0,0.06);

  /* Blog prose */
  --color-prose-heading: #0f172a;
  --color-prose-body: #475569;
  --color-prose-strong: #0f172a;
  --color-prose-blockquote: #64748b;
  --color-prose-blockquote-border: #6366f1;

  /* Gradients */
  --color-gradient-text: linear-gradient(135deg, #6366f1 0%, #8b5cf6 40%, #06b6d4 100%);
  --color-btn-gradient: linear-gradient(135deg, #6366f1 0%, #8b5cf6 100%);

  /* Transitions */
  --ease-premium: cubic-bezier(0.32, 0.72, 0, 1);
}

/* ========== DARK MODE ========== */
.dark {
  --color-glass-bg: rgba(15,23,42,0.55);
  --color-glass-bg-strong: rgba(15,23,42,0.78);
  --color-glass-bg-subtle: rgba(15,23,42,0.32);
  --color-glass-border: rgba(255,255,255,0.06);
  --color-glass-border-light: rgba(255,255,255,0.08);
  --color-text-primary: #f1f5f9;
  --color-text-secondary: #94a3b8;
  --color-text-tertiary: #64748b;
  --color-bg-page: #030712;
  --color-bg-page-alt: #060b16;
  --color-divider: rgba(255,255,255,0.06);
  --color-accent: #818cf8;
  --color-accent-glow: rgba(129,140,248,0.12);
  --color-accent-color: #818cf8;
  --color-card-outer-bg: rgba(255,255,255,0.02);
  --color-card-outer-ring: rgba(255,255,255,0.06);
  --color-card-inner-bg: rgba(15,23,42,0.85);
  --color-card-shadow: 0 1px 3px rgba(0,0,0,0.2), 0 8px 48px rgba(0,0,0,0.25), 0 2px 12px rgba(0,0,0,0.15);
  --color-card-shadow-hover: 0 2px 4px rgba(0,0,0,0.25), 0 12px 64px rgba(0,0,0,0.3), 0 4px 20px rgba(129,140,248,0.08);
  --color-nav-bg: rgba(15,23,42,0.8);
  --color-nav-border: rgba(255,255,255,0.06);

  --color-prose-heading: #f1f5f9;
  --color-prose-body: #94a3b8;
  --color-prose-strong: #e2e8f0;
  --color-prose-blockquote: #94a3b8;
  --color-prose-blockquote-border: #818cf8;

  --color-gradient-text: linear-gradient(135deg, #818cf8 0%, #a78bfa 40%, #22d3ee 100%);
  --color-btn-gradient: linear-gradient(135deg, #818cf8 0%, #a78bfa 100%);
}

/* ========== BASE STYLES ========== */
body {
  background: var(--color-bg-page);
  color: var(--color-text-primary);
  font-family: var(--font-sans);
  transition: background 0.7s cubic-bezier(0.32,0.72,0,1), color 0.7s cubic-bezier(0.32,0.72,0,1);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

html {
  scroll-behavior: smooth;
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
}

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

/* ========== SCROLLBAR ========== */
::-webkit-scrollbar { width: 5px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: rgba(148,163,184,0.25); border-radius: 3px; }

/* ========== SCROLL REVEAL ANIMATION ========== */
.reveal {
  opacity: 0;
  transform: translateY(32px);
  filter: blur(8px);
  transition: opacity 0.8s cubic-bezier(0.32,0.72,0,1),
              transform 0.8s cubic-bezier(0.32,0.72,0,1),
              filter 0.8s cubic-bezier(0.32,0.72,0,1);
  will-change: transform, opacity, filter;
}
.reveal.visible {
  opacity: 1;
  transform: translateY(0);
  filter: blur(0);
  will-change: auto;
}

/* ========== UTILITY CLASSES ========== */

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

/* Eyebrow badge */
.eyebrow {
  display: inline-flex;
  align-items: center;
  padding: 0.25rem 0.75rem;
  border-radius: 9999px;
  font-size: var(--text-eyebrow);
  font-weight: 600;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  background: rgba(99,102,241,0.08);
  color: #6366f1;
  border: 1px solid rgba(99,102,241,0.12);
}
.dark .eyebrow {
  background: rgba(129,140,248,0.1);
  color: #818cf8;
  border-color: rgba(129,140,248,0.15);
}

/* Section title */
.section-title {
  font-family: var(--font-display);
  font-size: var(--text-h1);
  font-weight: 700;
  letter-spacing: -0.03em;
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

/* Skill tag */
.skill-tag {
  display: inline-flex;
  align-items: center;
  gap: 0.375rem;
  padding: 0.375rem 0.875rem;
  background: var(--color-glass-bg);
  border: 1px solid var(--color-glass-border);
  border-radius: 9999px;
  font-size: var(--text-tag);
  font-weight: 500;
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  transition: all 0.5s cubic-bezier(0.32,0.72,0,1);
}
.skill-tag:hover {
  box-shadow: 0 0 24px var(--color-accent-glow);
  border-color: rgba(99,102,241,0.3);
}

/* ========== DOUBLE-BEZEL CARD ========== */
.card-outer {
  background: var(--color-card-outer-bg);
  border: 1px solid var(--color-card-outer-ring);
  border-radius: var(--radius-2xl);
  padding: 3px;
  transition: all 0.7s cubic-bezier(0.32,0.72,0,1);
}
.card-outer:hover {
  box-shadow: var(--color-card-shadow-hover);
}
.card-inner {
  background: var(--color-card-inner-bg);
  border-radius: calc(2rem - 3px);
  overflow: hidden;
  transition: box-shadow 0.7s cubic-bezier(0.32,0.72,0,1);
}

/* ========== BUTTONS ========== */
.btn-primary {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.625rem 1.25rem;
  border-radius: 9999px;
  font-size: var(--text-body-sm);
  font-weight: 600;
  background: var(--color-btn-gradient);
  color: #fff;
  transition: all 0.6s cubic-bezier(0.32,0.72,0,1);
  box-shadow: 0 4px 24px rgba(99,102,241,0.25);
}
.btn-primary:hover {
  box-shadow: 0 8px 40px rgba(99,102,241,0.4);
  transform: scale(1.02);
}
.btn-primary:active { transform: scale(0.98); }

.btn-icon-nest {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 1.75rem;
  height: 1.75rem;
  border-radius: 50%;
  background: rgba(255,255,255,0.2);
  transition: all 0.6s cubic-bezier(0.32,0.72,0,1);
}
.btn-primary:hover .btn-icon-nest {
  transform: translateX(2px) translateY(-1px);
  background: rgba(255,255,255,0.3);
}

.btn-secondary {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.625rem 1.25rem;
  border-radius: 9999px;
  font-size: var(--text-body-sm);
  font-weight: 600;
  transition: all 0.6s cubic-bezier(0.32,0.72,0,1);
  color: var(--color-text-secondary);
}
.btn-secondary:hover { background: var(--color-glass-bg); }

/* ========== DIVIDER ========== */
.glass-divider {
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--color-divider), transparent);
}

/* ========== EXP SUB-CARD ========== */
.exp-sub-card {
  background: var(--color-glass-bg-subtle);
  border: 1px solid var(--color-glass-border);
  border-radius: var(--radius-md);
  padding: 0.75rem 1rem;
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  transition: all 0.5s cubic-bezier(0.32,0.72,0,1);
}
.exp-sub-card:hover {
  background: var(--color-glass-bg);
  border-color: rgba(99,102,241,0.2);
}

/* ========== METRIC BADGE ========== */
.metric-badge {
  display: inline-flex;
  align-items: center;
  padding: 0.2rem 0.55rem;
  border-radius: var(--radius-sm);
  font-size: var(--text-caption);
  font-weight: 600;
  background: rgba(34,197,94,0.08);
  color: #22c55e;
  white-space: nowrap;
}

/* ========== SECTION LAYOUT ========== */
.section {
  padding-top: var(--spacing-section-py);
  padding-bottom: var(--spacing-section-py);
  position: relative;
}
@media (min-width: 1024px) {
  .section {
    padding-top: 8rem;
    padding-bottom: 8rem;
  }
}

.section-alt { background: var(--color-bg-page-alt); }
.section-main { background: var(--color-bg-page); }

/* ========== BLOG PROSE ========== */
.prose {
  font-size: var(--text-body-lg);
  line-height: 1.85;
  color: var(--color-prose-body);
  word-break: break-word;
}
.prose > *:first-child { margin-top: 0; }
.prose > *:last-child { margin-bottom: 0; }

.prose h1 {
  font-family: var(--font-display);
  font-size: var(--text-h1);
  font-weight: 700;
  color: var(--color-prose-heading);
  margin-top: 2.5rem;
  margin-bottom: 1.25rem;
  letter-spacing: -0.02em;
}
.prose h2 {
  font-family: var(--font-display);
  font-size: var(--text-h2);
  font-weight: 700;
  color: var(--color-prose-heading);
  margin-top: 2.5rem;
  margin-bottom: 1rem;
  letter-spacing: -0.015em;
  padding-bottom: 0.5rem;
  border-bottom: 1px solid var(--color-divider);
}
.prose h3 {
  font-family: var(--font-display);
  font-size: var(--text-h3);
  font-weight: 600;
  color: var(--color-prose-heading);
  margin-top: 1.75rem;
  margin-bottom: 0.75rem;
}
.prose h2 + h3 { margin-top: 0.5rem; }

.prose p {
  margin-bottom: 1.25rem;
  color: var(--color-prose-body);
}
.prose strong {
  color: var(--color-prose-strong);
  font-weight: 600;
}
.prose a {
  color: var(--color-accent);
  text-decoration: underline;
  text-underline-offset: 2px;
  transition: opacity 0.3s ease;
}
.prose a:hover { opacity: 0.75; }

.prose ul, .prose ol {
  padding-left: 1.5rem;
  margin-bottom: 1.25rem;
  margin-top: 0;
}
.prose ul { list-style-type: disc; }
.prose ol { list-style-type: decimal; }
.prose ul ul, .prose ol ol, .prose ul ol, .prose ol ul {
  margin-bottom: 0;
  margin-top: 0.25rem;
}
.prose li {
  margin-bottom: 0.5rem;
  line-height: 1.85;
  color: var(--color-prose-body);
}
.prose li::marker { color: var(--color-text-tertiary); }
.prose li:last-child { margin-bottom: 0; }

.prose blockquote {
  border-left: 3px solid var(--color-prose-blockquote-border);
  padding: 1rem 1.25rem;
  margin: 1.75rem 0;
  color: var(--color-prose-blockquote);
  background: var(--color-glass-bg);
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
}
.prose blockquote p { margin-bottom: 0.5rem; }
.prose blockquote p:last-child { margin-bottom: 0; }

.prose hr {
  border: none;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--color-divider), transparent);
  margin: 2rem 0;
}

.prose img {
  max-width: 100%;
  height: auto;
  border-radius: var(--radius-lg);
  margin: 1.5rem auto;
  display: block;
}

.prose code {
  font-family: 'SF Mono', 'Fira Code', 'Cascadia Code', monospace;
  font-size: 0.875em;
  background: var(--color-glass-bg);
  padding: 0.15em 0.4em;
  border-radius: 4px;
  border: 1px solid var(--color-glass-border);
}

.prose pre {
  background: var(--color-glass-bg-strong);
  border: 1px solid var(--color-glass-border);
  border-radius: var(--radius-lg);
  padding: 1rem 1.25rem;
  overflow-x: auto;
  margin: 1.5rem 0;
  font-size: 0.8125rem;
  line-height: 1.7;
}
.prose pre code {
  background: none;
  padding: 0;
  border: none;
  font-size: inherit;
}

/* ========== BLOG NAV BAR ========== */
.blog-nav {
  position: sticky;
  top: 0;
  z-index: 50;
  background: var(--color-nav-bg);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--color-nav-border);
}

/* ========== FLOATING NAV PILL ========== */
.nav-pill {
  background: rgba(255,255,255,0.92);
  border: 1px solid rgba(0,0,0,0.1);
  backdrop-filter: blur(24px);
  -webkit-backdrop-filter: blur(24px);
  border-radius: 9999px;
  box-shadow: 0 1px 3px rgba(0,0,0,0.06), 0 4px 16px rgba(0,0,0,0.08), 0 0 0 1px rgba(99,102,241,0.04);
  transition: all 0.7s cubic-bezier(0.32,0.72,0,1);
}
.dark .nav-pill {
  background: rgba(15,23,42,0.94);
  border-color: rgba(255,255,255,0.12);
  box-shadow: 0 1px 3px rgba(0,0,0,0.4), 0 4px 20px rgba(0,0,0,0.5), 0 0 0 1px rgba(129,140,248,0.08);
}
.nav-pill.scrolled {
  box-shadow: 0 2px 4px rgba(0,0,0,0.08), 0 12px 48px rgba(0,0,0,0.12), 0 0 0 1px rgba(99,102,241,0.08);
}
.dark .nav-pill.scrolled {
  box-shadow: 0 2px 4px rgba(0,0,0,0.5), 0 12px 48px rgba(0,0,0,0.6), 0 0 0 1px rgba(129,140,248,0.12);
}

.nav-link {
  font-size: var(--text-body-sm);
  font-weight: 500;
  color: var(--color-text-tertiary);
  transition: all 0.5s cubic-bezier(0.32,0.72,0,1);
  position: relative;
}
.nav-link::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: 50%;
  transform: translateX(-50%);
  width: 0;
  height: 2px;
  background: var(--color-accent);
  border-radius: 1px;
  transition: width 0.5s cubic-bezier(0.32,0.72,0,1);
}
.nav-link:hover { color: var(--color-text-secondary); }
.nav-link.active {
  color: var(--color-accent);
  font-weight: 600;
}
.nav-link.active::after { width: 60%; }

/* ========== MOBILE MENU ========== */
.hamburger-line {
  display: block;
  width: 18px;
  height: 2px;
  background: var(--color-text-primary);
  border-radius: 2px;
  transition: all 0.5s cubic-bezier(0.32,0.72,0,1);
  transform-origin: center;
}
.mobile-menu-active .hamburger-line:nth-child(1) {
  transform: translateY(6px) rotate(45deg);
}
.mobile-menu-active .hamburger-line:nth-child(2) {
  opacity: 0;
  transform: scaleX(0);
}
.mobile-menu-active .hamburger-line:nth-child(3) {
  transform: translateY(-6px) rotate(-45deg);
}

/* ========== SECTION HEIGHT ========== */
section[id]:not(#hero) {
  min-height: 100dvh;
  display: flex;
  flex-direction: column;
  scroll-margin-top: 90px;
}
section[id]:not(#hero) > [class*="max-w-"] {
  margin-top: auto;
  margin-bottom: auto;
}

/* ========== PROGRESS BAR ========== */
.top-progress {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 2px;
  z-index: 60;
  pointer-events: none;
  background: transparent;
}
.top-progress-fill {
  height: 100%;
  width: 0%;
  background: linear-gradient(90deg, #6366f1, #8b5cf6, #06b6d4);
  box-shadow: 0 0 8px var(--color-accent-glow), 0 0 2px rgba(99,102,241,0.3);
  transition: width 0.15s linear;
  will-change: width;
}
.dark .top-progress-fill {
  background: linear-gradient(90deg, #818cf8, #a78bfa, #22d3ee);
}

/* ========== HERO ORBS ========== */
.hero-orb {
  position: absolute;
  border-radius: 50%;
  filter: blur(100px);
  opacity: 0.5;
  pointer-events: none;
  animation: orb-float 10s cubic-bezier(0.32,0.72,0,1) infinite;
}
.hero-orb:nth-child(1) { background: #818cf8; width: 350px; height: 350px; top: -100px; right: -80px; animation-delay: 0s; }
.hero-orb:nth-child(2) { background: #a78bfa; width: 220px; height: 220px; top: 35%; right: 25%; animation-delay: -3s; }
.hero-orb:nth-child(3) { background: #22d3ee; width: 200px; height: 200px; bottom: -50px; left: -50px; animation-delay: -6s; }
@keyframes orb-float {
  0%, 100% { transform: translate(0, 0) scale(1); }
  33% { transform: translate(20px, -25px) scale(1.06); }
  66% { transform: translate(-15px, 15px) scale(0.94); }
}

/* ========== HERO BIO QUOTE CARD ========== */
.hero-bio {
  border-left: 3px solid #6366f1;
  padding-left: 1rem;
  background: var(--color-glass-bg);
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  color: var(--color-text-secondary);
  font-size: var(--text-body-lg);
  line-height: 1.7;
}
.dark .hero-bio { border-left-color: #818cf8; }

/* ========== HERO CARD FUSION (Mobile) ========== */
.hero-card { display: block; }
.hero-avatar {
  width: 110px;
  aspect-ratio: 9 / 16;
  flex-shrink: 0;
  border-radius: 1rem;
  padding: 2px;
  background: linear-gradient(135deg, #6366f1, #8b5cf6, #06b6d4);
  box-shadow: 0 0 32px var(--color-accent-glow), 0 0 64px rgba(139,92,246,0.08);
}
.hero-avatar img {
  width: 100%;
  height: 100%;
  border-radius: calc(1rem - 2px);
  object-fit: cover;
  display: block;
}
.hero-name-block { flex: 1; min-width: 0; padding-top: 10px; }
.hero-greeting { font-size: 0.9375rem; color: var(--color-text-tertiary); margin-bottom: 0.125rem; font-weight: 500; }
.hero-name-cn {
  font-family: var(--font-display);
  font-size: 3.125rem;
  font-weight: 700;
  line-height: 1.1;
  letter-spacing: -0.02em;
  margin-bottom: 0.125rem;
}
.hero-name-en { font-family: var(--font-sans); font-size: 1.3125rem; font-weight: 600; color: var(--color-text-secondary); letter-spacing: 0.01em; }
.hero-card-status {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.375rem 0.75rem;
  border-radius: 9999px;
  font-size: 0.6875rem;
  font-weight: 500;
  background: var(--color-glass-bg-subtle) padding-box,
              linear-gradient(135deg, #6366f1, #8b5cf6, #06b6d4) border-box;
  border: 1px solid transparent;
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  color: var(--color-text-secondary);
  width: 100%;
  justify-content: center;
}
.hero-tags-break { display: none; }
.hero-ctas { flex-wrap: wrap; gap: 0.75rem; justify-content: center; }

/* ========== MENU OVERLAY ========== */
.menu-overlay {
  position: fixed;
  inset: 0;
  z-index: 45;
  background: rgba(255,255,255,0.85);
  backdrop-filter: blur(40px);
  -webkit-backdrop-filter: blur(40px);
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.6s cubic-bezier(0.32,0.72,0,1);
}
.dark .menu-overlay { background: rgba(2,6,18,0.88); }
.menu-overlay.open {
  opacity: 1;
  pointer-events: auto;
}
.menu-link {
  display: block;
  font-family: var(--font-display);
  font-size: 1.75rem;
  font-weight: 600;
  letter-spacing: -0.02em;
  padding: 0.75rem 0;
  color: var(--color-text-primary);
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.6s cubic-bezier(0.32,0.72,0,1),
              transform 0.6s cubic-bezier(0.32,0.72,0,1),
              color 0.5s ease;
}
.menu-overlay.open .menu-link {
  opacity: 1;
  transform: translateY(0);
}
.menu-link:hover { color: var(--color-accent); }

/* ========== HAMBURGER MORPH ========== */
.hamburger-line {
  display: block;
  width: 20px;
  height: 1.5px;
  background: var(--color-text-primary);
  border-radius: 9999px;
  transition: all 0.5s cubic-bezier(0.32,0.72,0,1);
  position: absolute;
  left: 50%;
  transform: translateX(-50%);
}
.hamburger-line:nth-child(1) { top: 8px; }
.hamburger-line:nth-child(2) { top: 16px; }
.hamburger-line:nth-child(3) { top: 24px; }
.hamburger.open .hamburger-line:nth-child(1) {
  top: 16px;
  transform: translateX(-50%) rotate(45deg);
}
.hamburger.open .hamburger-line:nth-child(2) {
  opacity: 0;
  transform: translateX(-50%) scaleX(0);
}
.hamburger.open .hamburger-line:nth-child(3) {
  top: 16px;
  transform: translateX(-50%) rotate(-45deg);
}

/* ========== SKILL REEL (老虎机窗口) ========== */
.skill-reel {
  position: relative;
  width: 100%;
  height: 5.2rem;
  overflow: hidden;
}
.skill-reel::before {
  content: '';
  position: absolute;
  left: 0;
  top: 50%;
  transform: translateY(-50%);
  width: 2.5px;
  height: 1.35rem;
  border-radius: 2px;
  background: linear-gradient(180deg, #6366f1, #8b5cf6, #06b6d4);
  z-index: 2;
  pointer-events: none;
}
.skill-reel-track {
  position: relative;
  width: 100%;
  height: 100%;
}
.skill-reel-item {
  position: absolute;
  left: 0;
  right: 0;
  top: 50%;
  height: 1.733rem;
  margin-top: -0.867rem;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.8125rem;
  font-weight: 500;
  color: var(--color-text-tertiary);
  transition: transform 0.5s cubic-bezier(0.32,0.72,0,1),
              opacity 0.5s cubic-bezier(0.32,0.72,0,1),
              font-size 0.5s cubic-bezier(0.32,0.72,0,1),
              font-weight 0.5s cubic-bezier(0.32,0.72,0,1),
              color 0.5s cubic-bezier(0.32,0.72,0,1);
  pointer-events: none;
  white-space: nowrap;
}
.skill-reel-item.active {
  font-weight: 700;
  font-size: 0.9375rem;
}
.skill-reel-item.dim { opacity: 0.42; color: var(--color-text-tertiary); }
.skill-reel-item.off { opacity: 0; pointer-events: none; }

/* ========== SKILL DETAIL EXPAND ========== */
.skill-detail-card {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.6s cubic-bezier(0.32,0.72,0,1),
              opacity 0.5s cubic-bezier(0.32,0.72,0,1),
              margin 0.6s cubic-bezier(0.32,0.72,0,1);
  opacity: 0;
  margin-top: 0;
}
.skill-detail-card.expanded {
  max-height: 300px;
  opacity: 1;
  margin-top: 1rem;
}
.skill-card-clickable { cursor: pointer; position: relative; }
.skill-card-clickable::after {
  content: '点击查看详情';
  position: absolute;
  bottom: 0.5rem;
  right: 0.75rem;
  font-size: var(--text-eyebrow);
  color: var(--color-text-tertiary);
  opacity: 0;
  transition: opacity 0.5s ease;
}
.skill-card-clickable:hover::after { opacity: 1; }
.skill-mobile-desc { display: none; }

/* ========== CAROUSEL ========== */
.carousel-container { position: relative; }
.carousel-viewport { overflow: hidden; }
.carousel-track {
  display: flex;
  gap: 1rem;
  transition: transform 0.6s cubic-bezier(0.32,0.72,0,1);
  align-items: stretch;
}
.carousel-card {
  flex: 0 0 88%;
  opacity: 0.3;
  transition: opacity 0.5s cubic-bezier(0.32,0.72,0,1);
  pointer-events: none;
  user-select: none;
}
@media (min-width: 640px) {
  .carousel-card { flex: 0 0 88%; }
}
.carousel-card.active { opacity: 1; pointer-events: auto; user-select: auto; }

.carousel-arrow {
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  z-index: 10;
  width: 2.5rem;
  height: 2.5rem;
  border-radius: 50%;
  border: 1px solid var(--color-glass-border);
  background: var(--color-glass-bg-strong);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: all 0.5s cubic-bezier(0.32,0.72,0,1);
  color: var(--color-accent);
  animation: arrow-glow 2.5s cubic-bezier(0.32,0.72,0,1) infinite;
}
@keyframes arrow-glow {
  0%, 100% { box-shadow: 0 0 8px rgba(99,102,241,0.1); }
  50% { box-shadow: 0 0 20px rgba(99,102,241,0.25); }
}
.carousel-arrow:hover {
  box-shadow: 0 0 32px rgba(99,102,241,0.35);
  transform: translateY(-50%) scale(1.1);
  animation: none;
}
.carousel-arrow-left  { left: -0.75rem; }
.carousel-arrow-right { right: -0.75rem; }

.carousel-dots { display: flex; justify-content: center; gap: 0.5rem; margin-top: 1rem; }
.carousel-dot {
  width: 7px; height: 7px; border-radius: 50%; border: none; cursor: pointer; padding: 0;
  transition: all 0.5s cubic-bezier(0.32,0.72,0,1);
  background: var(--color-glass-border);
}
.carousel-dot.active {
  background: #6366f1;
  box-shadow: 0 0 12px var(--color-accent-glow);
  width: 22px;
  border-radius: 4px;
}

/* ========== EXPERIENCE CARD BRAND COLOR ACCENTS ========== */
#experience .carousel-card:nth-child(1) .card-inner { border-left: 3px solid #22c55e; }
#experience .carousel-card:nth-child(2) .card-inner { border-left: 3px solid #3b82f6; }
#experience .carousel-card:nth-child(3) .card-inner { border-left: 3px solid #f97316; }
#experience .carousel-card:nth-child(4) .card-inner { border-left: 3px solid #f59e0b; }

/* ========== SIDE NAVIGATION ========== */
.side-nav {
  position: fixed;
  right: 1.25rem;
  top: 50%;
  transform: translateY(-50%);
  z-index: 50;
  display: flex;
  flex-direction: column;
  align-items: center;
}
.side-nav-track {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0;
  padding: 0.75rem 0.5rem;
  border-radius: 9999px;
  background: var(--color-glass-bg-strong);
  border: 1px solid var(--color-glass-border);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  box-shadow: 0 0 16px rgba(99,102,241,0.04);
  transition: all 0.6s cubic-bezier(0.32,0.72,0,1);
}
.side-nav-track:hover {
  border-color: rgba(99,102,241,0.2);
  box-shadow: 0 0 32px var(--color-accent-glow);
}
.side-nav-dot {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 2rem;
  height: 2rem;
  position: relative;
  cursor: pointer;
  text-decoration: none;
  transition: all 0.4s cubic-bezier(0.32,0.72,0,1);
  opacity: 0;
  transform: translateX(12px);
  animation: dot-enter 0.6s cubic-bezier(0.32,0.72,0,1) forwards;
}
.side-nav-dot:nth-child(1) { animation-delay: 0.3s; }
.side-nav-dot:nth-child(2) { animation-delay: 0.38s; }
.side-nav-dot:nth-child(3) { animation-delay: 0.46s; }
.side-nav-dot:nth-child(4) { animation-delay: 0.54s; }
.side-nav-dot:nth-child(5) { animation-delay: 0.62s; }
.side-nav-dot:nth-child(6) { animation-delay: 0.70s; }
.side-nav-dot:nth-child(7) { animation-delay: 0.78s; }
@keyframes dot-enter {
  to { opacity: 1; transform: translateX(0); }
}
.side-nav-dot::before {
  content: '';
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background: var(--color-text-tertiary);
  transition: all 0.5s cubic-bezier(0.32,0.72,0,1);
  z-index: 1;
}
.side-nav-dot::after {
  content: '';
  position: absolute;
  inset: 4px;
  border-radius: 50%;
  border: 1.5px solid transparent;
  transition: all 0.5s cubic-bezier(0.32,0.72,0,1);
  opacity: 0;
  transform: scale(0.6);
}
.side-nav-dot.active::before {
  width: 8px;
  height: 8px;
  background: #6366f1;
  box-shadow: 0 0 16px var(--color-accent-glow), 0 0 32px rgba(99,102,241,0.3);
  animation: dot-pulse 2.4s cubic-bezier(0.32,0.72,0,1) infinite;
}
@keyframes dot-pulse {
  0%, 100% { box-shadow: 0 0 16px var(--color-accent-glow), 0 0 32px rgba(99,102,241,0.3); }
  50% { box-shadow: 0 0 24px var(--color-accent-glow), 0 0 48px rgba(99,102,241,0.5); }
}
.dark .side-nav-dot.active::before {
  background: #818cf8;
  box-shadow: 0 0 16px rgba(129,140,248,0.35), 0 0 32px rgba(129,140,248,0.25);
  animation-name: dot-pulse-dark;
}
@keyframes dot-pulse-dark {
  0%, 100% { box-shadow: 0 0 16px rgba(129,140,248,0.35), 0 0 32px rgba(129,140,248,0.25); }
  50% { box-shadow: 0 0 24px rgba(129,140,248,0.5), 0 0 48px rgba(129,140,248,0.4); }
}
.side-nav-dot.active::after {
  opacity: 1;
  transform: scale(1);
  border-color: rgba(99,102,241,0.3);
  inset: 1px;
}
.dark .side-nav-dot.active::after { border-color: rgba(129,140,248,0.35); }
.side-nav-dot:hover::before {
  background: var(--color-accent);
  transform: scale(1.8);
  animation: none;
}
.side-nav-dot .side-nav-label {
  position: absolute;
  right: calc(100% + 10px);
  top: 50%;
  transform: translateY(-50%) translateX(8px);
  white-space: nowrap;
  font-size: var(--text-caption);
  font-weight: 600;
  color: var(--color-text-primary);
  background: var(--color-glass-bg-strong);
  border: 1px solid var(--color-glass-border);
  border-radius: 9999px;
  padding: 0.25rem 0.75rem;
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.4s cubic-bezier(0.32,0.72,0,1), transform 0.4s cubic-bezier(0.32,0.72,0,1);
  box-shadow: var(--color-card-shadow);
}
.side-nav-dot.active:hover .side-nav-label,
.side-nav-dot.active .side-nav-label.auto-reveal {
  opacity: 1;
  transform: translateY(-50%) translateX(0);
}
.side-nav-dot:not(:last-child) { margin-bottom: -2px; }

/* ========== EMAIL TOOLTIP ========== */
.email-icon { cursor: pointer; transition: color 0.5s ease; position: relative; }
.email-tooltip {
  position: absolute;
  top: 50%;
  left: calc(100% + 3px);
  transform: translateY(calc(-50% - 1.5px));
  padding: 6px 12px;
  border-radius: 10px;
  font-size: var(--text-caption);
  white-space: nowrap;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.5s ease;
  background: var(--color-glass-bg-strong);
  border: 1px solid var(--color-glass-border);
  color: var(--color-text-primary);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
}
.email-tooltip.show { opacity: 1; pointer-events: auto; }

/* ========== ACCORDION CHEVRON (mobile) ========== */
.accordion-chevron { display: none; }

/* ========== SKILLS BENTO GRID (desktop) ========== */
@media (min-width: 768px) {
  .skills-grid {
    /* grid-template-columns handled by Tailwind md:grid-cols-24 */
  }
  #skillProductCard  { grid-row: 1; grid-column: 1 / span 8; }
  #skillAICard       { grid-row: 1; grid-column: 9 / span 8; }
  #skillEnglishCard  { grid-row: 1; grid-column: 17 / span 8; }
  #skillDetailCard,
  #skillAIDetailCard,
  #skillEnglishDetailCard { grid-row: 2; grid-column: 1 / -1; }
}

/* ========== MOBILE (< 768px) ========== */
@media (max-width: 767px) {
  .card-outer { border-radius: var(--radius-xl); padding: 2px; }
  .card-inner { border-radius: calc(1.5rem - 2px); }

  .carousel-arrow { width: 2rem; height: 2rem; }
  .carousel-arrow-left { left: -0.25rem; }
  .carousel-arrow-right { right: -0.25rem; }

  .menu-link { font-size: 1.25rem; padding: 0.5rem 0; }

  .hero-orb:nth-child(1) { width: 180px; height: 180px; top: -40px; right: -30px; }
  .hero-orb:nth-child(2) { width: 110px; height: 110px; }
  .hero-orb:nth-child(3) { width: 100px; height: 100px; }

  .hero-status { width: 100% !important; justify-content: center !important; font-size: 0.75rem !important; }
  .hero-tags { flex-wrap: wrap !important; justify-content: center !important; gap: 0.5rem !important; }
  .hero-tags-break { display: block; flex-basis: 100%; height: 0; }
  .hero-bio { font-size: 0.8125rem !important; line-height: 1.65 !important; }
  .hero-ctas { flex-direction: column !important; width: 100% !important; gap: 0.625rem !important; }
  .hero-ctas .btn-primary,
  .hero-ctas .btn-secondary { width: 100% !important; justify-content: center !important; }
  #hero { padding-top: 5rem !important; padding-bottom: 2.5rem !important; min-height: 100dvh !important; }
  #hero .max-w-6xl { padding: 0.5rem 0.75rem !important; }
  #navbar { top: 0.75rem !important; }

  /* Experience: accordion mode */
  #experience .carousel-track { flex-direction: column; gap: 1rem; transform: none !important; }
  #experience .carousel-card { flex: 1 1 auto; opacity: 1 !important; pointer-events: auto !important; }
  #experience .carousel-arrow, #experience .carousel-dots { display: none !important; }
  #experience .accordion-header::after { display: none !important; }
  #experience .accordion-header {
    cursor: pointer;
    position: relative;
    padding: 1rem 3rem 0.875rem 1rem !important;
  }
  #experience .accordion-header > div:first-child {
    flex-wrap: wrap !important;
    row-gap: 0.25rem !important;
  }
  #experience .accordion-header > div:first-child > span:last-child {
    flex-basis: 100% !important;
    margin-left: 0 !important;
    padding-left: 3.5rem !important;
    font-size: 0.75rem !important;
    white-space: normal !important;
  }
  #experience .accordion-chevron {
    display: flex !important;
    align-items: center;
    justify-content: center;
    position: absolute;
    right: 0.75rem;
    top: 50%;
    transform: translateY(-50%);
    width: 1.75rem;
    height: 1.75rem;
    border-radius: 50%;
    background: var(--color-glass-bg);
    border: 1px solid var(--color-glass-border);
    color: var(--color-text-tertiary);
    font-size: 0.75rem;
    transition: transform 0.5s cubic-bezier(0.32,0.72,0,1),
                background 0.5s ease, border-color 0.5s ease, color 0.5s ease;
  }
  #experience .carousel-card.accordion-open .accordion-chevron {
    transform: translateY(-50%) rotate(180deg);
    background: rgba(99,102,241,0.08);
    border-color: rgba(99,102,241,0.22);
    color: var(--color-accent);
  }
  #experience .accordion-header h3 { font-size: 0.9375rem !important; line-height: 1.3 !important; }
  #experience .accordion-header p { font-size: 0.8125rem !important; }
  #experience .accordion-header .gap-3 { gap: 0.75rem !important; }
  #experience .accordion-header .w-10.h-10 {
    width: 2.75rem !important;
    height: 2.75rem !important;
    border-radius: 0.875rem !important;
  }
  #experience .accordion-header .eyebrow { font-size: 0.625rem !important; padding: 0.22rem 0.55rem !important; }
  #experience .carousel-card .card-inner > .glass-divider { display: none !important; }
  #experience .carousel-card .card-inner > .exp-content {
    max-height: 0; overflow: hidden; padding-top: 0 !important; padding-bottom: 0 !important;
    transition: max-height 0.5s ease;
  }
  #experience .carousel-card.accordion-open .card-inner > .exp-content {
    max-height: 4000px; padding-top: 0.75rem !important; padding-bottom: 0.75rem !important;
  }
  #experience .activity-img { height: 150px; object-fit: cover; }
  #experience .exp-content { padding: 0.75rem !important; gap: 0.5rem !important; }
  #experience .exp-sub-card { padding: 0.5rem 0.75rem !important; }
  #experience .exp-sub-card h4 { font-size: 0.75rem !important; }
  #experience .exp-sub-card p,
  #experience .exp-sub-card li { font-size: 0.6875rem !important; line-height: 1.55 !important; }
  #experience .exp-sub-card .gap-2\.5 { gap: 0.5rem !important; }
  #experience .metric-badge { font-size: 0.5625rem !important; padding: 0.1rem 0.35rem !important; }

  /* Skills: mobile vertical + horizontal reel */
  #skills .grid {
    gap: 0.875rem !important;
    grid-template-columns: 1fr !important;
  }
  #skills .skill-detail-card { display: none !important; }
  #skills .skill-mobile-desc {
    display: block !important;
    font-size: 0.75rem !important;
    line-height: 1.6 !important;
    color: var(--color-text-secondary) !important;
    margin-top: 0.625rem !important;
    padding-top: 0.625rem !important;
    border-top: 1px solid var(--color-glass-border) !important;
    text-align: justify !important;
  }
  #skills .skill-card-clickable { cursor: default !important; }
  #skills .skill-card-clickable::after { display: none !important; }
  #skills .skill-card-clickable .card-inner { padding: 1rem 0.875rem !important; }
  #skills .skill-card-clickable .w-10.h-10 {
    width: 2rem !important;
    height: 2rem !important;
    margin-bottom: 0.5rem !important;
    margin-left: auto !important;
    margin-right: auto !important;
  }
  #skills .skill-card-clickable .w-10.h-10 i { font-size: 1rem !important; }
  #skills .skill-card-clickable h3 { font-size: 0.875rem !important; margin-bottom: 0.25rem !important; }
  #skills .skill-reel {
    height: 2.2rem !important;
    mask-image: linear-gradient(to right, transparent 0%, black 8%, black 92%, transparent 100%) !important;
    -webkit-mask-image: linear-gradient(to right, transparent 0%, black 8%, black 92%, transparent 100%) !important;
  }
  #skills .skill-reel::before { display: none !important; }
  #skills .skill-reel-track {
    display: flex !important;
    align-items: center !important;
    position: static !important;
    height: 100% !important;
    transition: transform 0.45s cubic-bezier(0.32,0.72,0,1) !important;
    will-change: transform !important;
  }
  #skills .skill-reel-item {
    position: static !important;
    left: auto !important;
    right: auto !important;
    top: auto !important;
    flex: 0 0 calc(100% / 3) !important;
    height: auto !important;
    margin-top: 0 !important;
    text-align: center !important;
    overflow: hidden !important;
    text-overflow: ellipsis !important;
    font-size: 0.6875rem !important;
    transform: scale(0.88) !important;
    opacity: 0.42 !important;
    transition: all 0.45s cubic-bezier(0.32,0.72,0,1) !important;
  }
  #skills .skill-reel-item.active {
    font-size: 0.8125rem !important;
    opacity: 1 !important;
    transform: scale(1) !important;
  }
  #skills .skill-reel-item.dim { opacity: 0.42 !important; transform: scale(0.88) !important; }
  #skills .skill-reel-item.off { opacity: 0.42 !important; transform: scale(0.88) !important; }

  .email-tooltip { left: auto !important; right: 0 !important; top: calc(100% + 6px) !important; transform: none !important; }

  .side-nav { display: none !important; }
  .top-progress { height: 2px; }

  section[id]:not(#hero) { min-height: auto !important; }
  #education, #skills, #experience, #blog, #projects { padding-top: 3.5rem !important; padding-bottom: 3.5rem !important; }
  #campus { padding-top: 3.5rem !important; }

  #education .md\:border-r { border-bottom: 1px solid var(--color-divider); padding-bottom: 1rem; }
  #blog a.card-outer .btn-primary { width: 100%; justify-content: center; }

  p, li { line-height: 1.7; }

  .hero-card { display: block; }
  .hero-card .card-outer { border-radius: var(--radius-xl); padding: 2px; }
  .hero-card .card-inner { border-radius: calc(1.5rem - 2px); padding: 1.25rem !important; }

  #viewport-scale #hero {
    min-height: calc(100dvh * var(--inv-scale, 1)) !important;
  }
  html { overflow-x: clip; }

  /* ── Blog Prose Mobile ── */
  .prose { font-size: 0.9375rem; line-height: 1.8; }
  .prose h1 { font-size: 1.375rem; margin-top: 2rem; }
  .prose h2 { font-size: 1.25rem; margin-top: 2rem; }
  .prose h3 { font-size: 1.0625rem; margin-top: 1.5rem; }
  .prose blockquote { padding: 0.75rem 1rem; margin: 1.25rem 0; }
  .prose blockquote p { font-size: 0.875rem; }
  .prose pre { padding: 0.75rem 1rem; font-size: 0.75rem; }
  article { padding: 2rem 0.875rem !important; }
  article header h1 { font-size: clamp(1.375rem, 5vw, 1.75rem) !important; }
  article header p { font-size: 0.9375rem !important; }
}