/* =================================================================
   NJNavigator v0 — stylesheet
   Visual direction: Apple Support + Structured / Duna + university portal
   Mobile-first, glassmorphism on a soft Nanjing-inspired backdrop.
   ================================================================= */

/* ---------- Design tokens ---------- */
:root {
  --navy: #0B1F3A;
  --soft-blue: #6F95BD;
  --brick: #9E3F35;
  --beige: #F4EFE7;
  --glass: rgba(255, 255, 255, 0.68);
  --glass-strong: rgba(255, 255, 255, 0.82);
  --text: #102033;
  --text-soft: #3b4a64;
  --line: rgba(11, 31, 58, 0.10);
  --line-strong: rgba(11, 31, 58, 0.18);
  --shadow-sm: 0 1px 2px rgba(11, 31, 58, 0.05), 0 2px 6px rgba(11, 31, 58, 0.05);
  --shadow-md: 0 10px 24px rgba(11, 31, 58, 0.08), 0 2px 6px rgba(11, 31, 58, 0.05);
  --shadow-lg: 0 24px 60px rgba(11, 31, 58, 0.14);
  --radius-sm: 10px;
  --radius: 18px;
  --radius-lg: 26px;
  --ease: cubic-bezier(.2,.7,.2,1);
  --fs-base: 16px;
  --container: 1200px;
}

/* ---------- Reset ---------- */
*, *::before, *::after { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
img, svg { display: block; max-width: 100%; }
button { font: inherit; color: inherit; cursor: pointer; border: 0; background: none; }
a { color: inherit; text-decoration: none; }
ul, ol { padding: 0; margin: 0; list-style: none; }

/* ---------- Base ---------- */
body {
  font-family: 'Inter', 'Noto Sans SC', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
  font-size: var(--fs-base);
  line-height: 1.6;
  color: var(--text);
  background: linear-gradient(180deg, #FBF8F2 0%, #F1ECE2 100%);
  min-height: 100vh;
  overflow-x: hidden;
}

html[data-lang="zh"] body { font-family: 'Noto Sans SC', 'Inter', system-ui, sans-serif; }

h1, h2, h3, h4, h5 { color: var(--navy); margin: 0 0 .4em; font-weight: 600; letter-spacing: -0.01em; }
h1 { font-size: clamp(2rem, 4vw + 1rem, 3.4rem); line-height: 1.1; }
h2 { font-size: clamp(1.7rem, 2.4vw + .8rem, 2.4rem); line-height: 1.18; }
h3 { font-size: clamp(1.15rem, .6vw + 1rem, 1.4rem); }
h4 { font-size: 1.05rem; }
h5 { font-size: .98rem; }
p  { margin: 0 0 .6em; color: var(--text-soft); }

.eyebrow {
  text-transform: uppercase;
  font-size: 0.75rem;
  letter-spacing: 0.16em;
  color: var(--brick);
  margin: 0 0 .6em;
  font-weight: 600;
}

.container {
  width: 100%;
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 22px;
}

/* ---------- Background texture ---------- */
.bg-texture {
  position: fixed; inset: 0;
  z-index: -1;
  pointer-events: none;
  opacity: 0.85;
}

/* ---------- Header / Navigation ---------- */
.site-header {
  position: sticky; top: 0;
  z-index: 50;
  backdrop-filter: saturate(180%) blur(14px);
  -webkit-backdrop-filter: saturate(180%) blur(14px);
  background: rgba(255, 255, 255, 0.6);
  border-bottom: 1px solid var(--line);
  transition: background .3s var(--ease), box-shadow .3s var(--ease);
}
.site-header.is-scrolled {
  background: rgba(255, 255, 255, 0.82);
  box-shadow: var(--shadow-sm);
}
.nav-wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  min-height: 64px;
}
.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--navy);
  font-weight: 600;
  font-size: 1.05rem;
  letter-spacing: -0.005em;
}
.brand-mark { display: inline-flex; }
.brand-tag {
  font-size: 0.72rem;
  font-weight: 500;
  color: var(--text-soft);
  background: rgba(111,149,189,0.14);
  padding: 2px 8px;
  border-radius: 999px;
  margin-left: 4px;
}

.primary-nav {
  display: flex;
  align-items: center;
  gap: 18px;
}
.primary-nav ul {
  display: flex;
  gap: 6px;
}
.primary-nav a {
  display: inline-block;
  padding: 8px 12px;
  border-radius: 10px;
  font-size: 0.95rem;
  color: var(--text);
  transition: background .2s var(--ease), color .2s var(--ease);
}
.primary-nav a:hover { background: rgba(11,31,58,0.06); color: var(--navy); }
.primary-nav a.is-active { color: var(--navy); background: rgba(111,149,189,0.18); }

.lang-toggle {
  border: 1px solid var(--line-strong);
  border-radius: 999px;
  padding: 6px 14px;
  font-size: 0.85rem;
  font-weight: 600;
  background: var(--glass);
  display: inline-flex;
  align-items: center;
  gap: 6px;
  transition: all .2s var(--ease);
}
.lang-toggle:hover { background: var(--glass-strong); border-color: var(--navy); }
.lang-toggle .lang-sep { color: var(--text-soft); font-weight: 400; }
html[data-lang="en"] .lang-toggle .lang-en { color: var(--navy); }
html[data-lang="en"] .lang-toggle .lang-zh { color: var(--text-soft); }
html[data-lang="zh"] .lang-toggle .lang-en { color: var(--text-soft); }
html[data-lang="zh"] .lang-toggle .lang-zh { color: var(--navy); }

.nav-toggle {
  display: none;
  width: 38px;
  height: 38px;
  border-radius: 10px;
  border: 1px solid var(--line-strong);
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 4px;
  background: var(--glass);
}
.nav-toggle span {
  display: block;
  width: 18px; height: 2px;
  background: var(--navy);
  border-radius: 2px;
  transition: transform .2s var(--ease), opacity .2s var(--ease);
}
.nav-toggle[aria-expanded="true"] span:nth-child(1) { transform: translateY(6px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] span:nth-child(3) { transform: translateY(-6px) rotate(-45deg); }

/* ---------- Hero ---------- */
.hero {
  position: relative;
  min-height: 78vh;
  display: flex;
  align-items: flex-end;
  padding: 80px 0 60px;
  overflow: hidden;
}
.hero-carousel {
  position: absolute;
  inset: 0;
  z-index: 0;
}
.hero-slides {
  position: relative;
  width: 100%;
  height: 100%;
}
.hero-slide {
  position: absolute; inset: 0;
  opacity: 0;
  transition: opacity 1.4s var(--ease);
  background-size: cover;
  background-position: center;
}
.hero-slide.is-active { opacity: 1; }
.hero-slide::before {
  content: "";
  position: absolute; inset: 0;
  background: linear-gradient(180deg, rgba(255,255,255,0.55) 0%, rgba(244,239,231,0.85) 100%);
}
/* placeholder visuals — each slide gets its own soft gradient + label */
.hero-slide[data-img="IMG-HERO-01"] { background-image: linear-gradient(135deg, #cdd9e8 0%, #9bb4d1 100%); }
.hero-slide[data-img="IMG-HERO-02"] { background-image: linear-gradient(135deg, #d9cfc5 0%, #9e7a6c 100%); }
.hero-slide[data-img="IMG-HERO-03"] { background-image: linear-gradient(135deg, #c7dde2 0%, #88a9b1 100%); }
.hero-slide[data-img="IMG-HERO-04"] { background-image: linear-gradient(135deg, #d4d8e0 0%, #6f95bd 100%); }
.hero-slide[data-img="IMG-HERO-05"] { background-image: linear-gradient(135deg, #e5ddd0 0%, #b5a07b 100%); }
.hero-slide::after {
  content: attr(data-img) "\A " attr(data-desc-en);
  white-space: pre;
  position: absolute;
  bottom: 24px; right: 24px;
  padding: 8px 14px;
  background: rgba(255,255,255,0.7);
  border: 1px solid var(--line);
  border-radius: 999px;
  font-size: 0.75rem;
  color: var(--text-soft);
  letter-spacing: 0.04em;
}
html[data-lang="zh"] .hero-slide::after {
  content: attr(data-img) "\A " attr(data-desc-zh);
}

.carousel-arrow {
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  width: 44px; height: 44px;
  border-radius: 50%;
  background: var(--glass-strong);
  border: 1px solid var(--line);
  box-shadow: var(--shadow-sm);
  font-size: 1.4rem;
  color: var(--navy);
  z-index: 3;
  transition: transform .2s var(--ease), background .2s var(--ease);
}
.carousel-arrow:hover { transform: translateY(-50%) scale(1.06); background: #fff; }
.carousel-arrow.prev { left: 16px; }
.carousel-arrow.next { right: 16px; }

.carousel-dots {
  position: absolute;
  bottom: 18px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  gap: 8px;
  z-index: 3;
}
.carousel-dots button {
  width: 8px; height: 8px;
  border-radius: 999px;
  background: rgba(11,31,58,0.25);
  transition: all .2s var(--ease);
}
.carousel-dots button.is-active { background: var(--navy); width: 24px; }

.hero-overlay {
  position: relative;
  z-index: 2;
  width: 100%;
}
.hero-card {
  max-width: 640px;
  padding: 36px 36px 32px;
  border-radius: var(--radius-lg);
}
.hero-title { margin-bottom: 12px; }
.hero-sub {
  font-size: 1.1rem;
  color: var(--text);
  margin-bottom: 24px;
}
.hero-cta {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  margin-bottom: 18px;
}
.hero-note {
  font-size: 0.8rem;
  color: var(--text-soft);
  margin: 0;
}

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 12px 22px;
  border-radius: 999px;
  font-weight: 600;
  font-size: 0.95rem;
  transition: transform .2s var(--ease), background .2s var(--ease), box-shadow .2s var(--ease);
  white-space: nowrap;
}
.btn-primary {
  background: var(--navy);
  color: #fff;
  box-shadow: 0 6px 18px rgba(11,31,58,0.22);
}
.btn-primary:hover { transform: translateY(-1px); background: #0d2547; }
.btn-ghost {
  background: rgba(255,255,255,0.7);
  border: 1px solid var(--line-strong);
  color: var(--navy);
}
.btn-ghost:hover { background: #fff; transform: translateY(-1px); }

/* ---------- Glass surface ---------- */
.glass {
  background: var(--glass);
  border: 1px solid rgba(255,255,255,0.7);
  border-radius: var(--radius);
  backdrop-filter: blur(16px) saturate(160%);
  -webkit-backdrop-filter: blur(16px) saturate(160%);
  box-shadow: var(--shadow-md);
}

/* ---------- Sections ---------- */
.section {
  padding: 92px 0;
  position: relative;
}
.section-tinted {
  background: linear-gradient(180deg, rgba(244,239,231,0.55) 0%, rgba(255,255,255,0.0) 100%);
}
.section-story {
  background:
    radial-gradient(1200px 600px at 80% 10%, rgba(111,149,189,0.18) 0%, transparent 60%),
    radial-gradient(800px 500px at 10% 90%, rgba(158,63,53,0.10) 0%, transparent 60%);
}
.section-head {
  max-width: 720px;
  margin: 0 0 38px;
}
.lede {
  font-size: 1.05rem;
  color: var(--text-soft);
}
.subhead {
  margin: 48px 0 18px;
  font-size: 1.25rem;
  color: var(--navy);
}

/* ---------- Grids ---------- */
.grid { display: grid; gap: 16px; }
.grid-2 { grid-template-columns: repeat(2, minmax(0,1fr)); }
.grid-3 { grid-template-columns: repeat(3, minmax(0,1fr)); }
.grid-4 { grid-template-columns: repeat(4, minmax(0,1fr)); }

/* ---------- Cards ---------- */
.card {
  padding: 22px 22px 20px;
  transition: transform .25s var(--ease), box-shadow .25s var(--ease);
  position: relative;
}
.card:hover { transform: translateY(-3px); box-shadow: var(--shadow-lg); }
.card-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 60px;
  height: 38px;
  padding: 0 14px;
  border-radius: 12px;
  background: var(--navy);
  color: #fff;
  font-weight: 700;
  letter-spacing: 0.04em;
  margin-bottom: 14px;
}

.app-card {
  padding: 20px;
  text-align: left;
  transition: transform .25s var(--ease), box-shadow .25s var(--ease);
}
.app-card:hover { transform: translateY(-2px); box-shadow: var(--shadow-lg); }
.app-icon {
  width: 46px; height: 46px;
  border-radius: 12px;
  background: linear-gradient(135deg, var(--soft-blue), var(--navy));
  color: #fff;
  display: flex; align-items: center; justify-content: center;
  font-size: 1.3rem;
  font-weight: 600;
  margin-bottom: 12px;
}

.tip { padding: 22px 24px; border-left: 3px solid var(--brick); }

/* ---------- Tags ---------- */
.tag {
  display: inline-block;
  padding: 4px 10px;
  border-radius: 999px;
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  margin-top: 10px;
}
.tag-ok { background: rgba(91, 145, 95, 0.14); color: #36603a; }
.tag-warn { background: rgba(158, 63, 53, 0.14); color: var(--brick); }

.placeholder-line {
  font-family: 'JetBrains Mono', 'Consolas', monospace;
  font-size: 0.82rem;
  color: var(--text-soft);
  background: rgba(11,31,58,0.05);
  border-radius: 8px;
  padding: 8px 12px;
  margin: 8px 0;
}

/* ---------- Campus points ---------- */
.point-id, .t-id, .map-id {
  display: inline-block;
  font-family: 'JetBrains Mono', 'Consolas', monospace;
  font-size: 0.7rem;
  letter-spacing: 0.08em;
  color: var(--text-soft);
  background: rgba(11,31,58,0.06);
  padding: 3px 8px;
  border-radius: 6px;
  margin-bottom: 10px;
}
.campus-point .bullet, .bullet { padding-left: 0; margin-top: 8px; }
.bullet li {
  position: relative;
  padding-left: 16px;
  font-size: 0.92rem;
  color: var(--text-soft);
  margin-bottom: 4px;
}
.bullet li::before {
  content: "";
  position: absolute;
  left: 0; top: 11px;
  width: 6px; height: 6px;
  background: var(--soft-blue);
  border-radius: 50%;
}

/* ---------- Food cards ---------- */
.food-card { padding: 20px; }
.sensory {
  margin: 8px 0 0;
  display: grid;
  grid-template-columns: 86px 1fr;
  gap: 4px 12px;
  font-size: 0.88rem;
}
.sensory dt { color: var(--navy); font-weight: 600; }
.sensory dd { margin: 0; color: var(--text-soft); font-family: 'JetBrains Mono', 'Consolas', monospace; font-size: 0.82rem; }

/* ---------- Image placeholder ---------- */
.img-ph {
  position: relative;
  aspect-ratio: 16 / 9;
  border-radius: var(--radius);
  background:
    repeating-linear-gradient(135deg, rgba(11,31,58,0.04) 0 12px, rgba(11,31,58,0.07) 12px 24px),
    linear-gradient(135deg, #e8ddd0, #cdd9e8);
  border: 1px dashed var(--line-strong);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 18px;
  color: var(--navy);
  overflow: hidden;
}
.img-ph::before {
  content: "Photo Placeholder";
  font-size: 0.75rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--brick);
  font-weight: 600;
  margin-bottom: 6px;
}
.img-ph::after {
  content: attr(data-img) "\A" attr(data-desc-en) "\A To be replaced by group photo or official image.";
  white-space: pre-line;
  font-size: 0.85rem;
  color: var(--text-soft);
  line-height: 1.5;
  max-width: 30ch;
}
html[data-lang="zh"] .img-ph::before { content: "图片占位"; }
html[data-lang="zh"] .img-ph::after {
  content: attr(data-img) "\A" attr(data-desc-zh) "\A 后续将由小组照片或官方图片替换。";
}
.img-ph.small { aspect-ratio: 4 / 3; margin-bottom: 14px; }

/* ---------- Map embed ---------- */
.map-embed {
  position: relative;
  width: 100%;
  border-radius: var(--radius);
  overflow: hidden;
  background: rgba(255,255,255,0.5);
  border: 1px solid var(--line);
  box-shadow: var(--shadow-sm);
}
.map-placeholder {
  aspect-ratio: 16 / 7;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 24px;
  text-align: center;
  background:
    repeating-linear-gradient(90deg, rgba(111,149,189,0.05) 0 18px, rgba(111,149,189,0.10) 18px 36px),
    repeating-linear-gradient(0deg, rgba(111,149,189,0.05) 0 18px, rgba(111,149,189,0.10) 18px 36px);
}
.map-placeholder p { color: var(--text-soft); font-size: 0.95rem; margin: 0; }
.route-card .map-embed { margin-top: 16px; }
.route-card .map-placeholder { aspect-ratio: 16 / 9; }

/* ---------- Timeline ---------- */
.timeline {
  position: relative;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
  margin-top: 8px;
}
.timeline::before {
  content: "";
  position: absolute;
  top: 28px;
  left: 6%;
  right: 6%;
  height: 2px;
  background: linear-gradient(90deg, var(--soft-blue), var(--brick));
  opacity: 0.4;
  z-index: 0;
}
.timeline-item {
  position: relative;
  padding: 22px 20px;
  background: var(--glass);
  border-radius: var(--radius);
  border: 1px solid rgba(255,255,255,0.7);
  box-shadow: var(--shadow-sm);
}
.timeline-item::before {
  content: "";
  position: absolute;
  top: -8px; left: 22px;
  width: 16px; height: 16px;
  background: #fff;
  border: 2px solid var(--brick);
  border-radius: 50%;
  box-shadow: 0 0 0 4px rgba(158,63,53,0.10);
}

/* ---------- Deep dive ---------- */
.deepdive { padding: 24px; }

/* ---------- Routes ---------- */
.route-card { padding: 24px; }
.route-card header { margin-bottom: 14px; }
.steps { display: grid; gap: 12px; }
.steps li {
  position: relative;
  padding: 14px 16px 14px 44px;
  background: rgba(255,255,255,0.55);
  border-radius: var(--radius-sm);
  border: 1px solid var(--line);
  counter-increment: step;
}
.steps { counter-reset: step; }
.steps li::before {
  content: counter(step);
  position: absolute;
  left: 14px; top: 14px;
  width: 22px; height: 22px;
  border-radius: 50%;
  background: var(--navy);
  color: #fff;
  display: flex; align-items: center; justify-content: center;
  font-size: 0.78rem;
  font-weight: 700;
}
.steps p { margin: 2px 0; font-size: 0.88rem; }

/* ---------- Phrases / refs ---------- */
.phrase-grid .phrase { padding: 16px 18px; }
.phrase h5 { margin-bottom: 4px; }
.phrase p { margin: 2px 0; font-size: 0.9rem; }
.refs { display: grid; gap: 6px; }
.refs li { font-size: 0.92rem; color: var(--text-soft); padding: 6px 0; border-bottom: 1px dashed var(--line); }
.refs li:last-child { border-bottom: 0; }

.qr-card { display: flex; flex-direction: column; align-items: center; text-align: center; padding: 24px; }
.qr-ph { margin: 8px 0 12px; padding: 10px; background: #fff; border-radius: 12px; border: 1px solid var(--line); }

/* ---------- Footer ---------- */
.site-footer {
  border-top: 1px solid var(--line);
  padding: 36px 0 48px;
  background: rgba(255,255,255,0.5);
  backdrop-filter: blur(12px);
}
.footer-wrap {
  display: grid;
  grid-template-columns: 1.2fr 1fr;
  gap: 22px;
  font-size: 0.9rem;
  color: var(--text-soft);
}
.footer-brand { color: var(--navy); font-weight: 700; margin: 0 0 4px; font-size: 1rem; }

/* ---------- Reveal on scroll ---------- */
.reveal {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity .8s var(--ease), transform .8s var(--ease);
}
.reveal.is-in { opacity: 1; transform: translateY(0); }

/* ---------- Language fade ---------- */
.lang-fading [data-i18n] { transition: opacity .25s ease; opacity: 0.1; }
[data-i18n] { transition: opacity .35s ease; }

/* ---------- Responsive ---------- */
@media (max-width: 960px) {
  .grid-4 { grid-template-columns: repeat(2, minmax(0,1fr)); }
  .grid-3 { grid-template-columns: repeat(2, minmax(0,1fr)); }
  .timeline { grid-template-columns: 1fr; }
  .timeline::before { display: none; }
  .footer-wrap { grid-template-columns: 1fr; }
}

@media (max-width: 720px) {
  .nav-toggle { display: flex; }
  .primary-nav {
    position: absolute;
    top: 64px; left: 0; right: 0;
    background: rgba(255,255,255,0.96);
    backdrop-filter: blur(20px);
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 12px 18px 18px;
    border-bottom: 1px solid var(--line);
    transform: translateY(-12px);
    opacity: 0;
    pointer-events: none;
    transition: opacity .25s var(--ease), transform .25s var(--ease);
  }
  .primary-nav.is-open {
    opacity: 1; transform: translateY(0); pointer-events: auto;
  }
  .primary-nav ul {
    flex-direction: column;
    gap: 2px;
    margin-bottom: 10px;
  }
  .primary-nav a { padding: 12px 14px; font-size: 1rem; }
  .lang-toggle { align-self: flex-start; }

  .section { padding: 64px 0; }
  .hero { min-height: 70vh; padding: 56px 0 40px; }
  .hero-card { padding: 26px 22px; }
  .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
  .carousel-arrow { width: 38px; height: 38px; }
  .sensory { grid-template-columns: 70px 1fr; }
  .brand-tag { display: none; }
}

@media (max-width: 420px) {
  .hero-cta .btn { flex: 1 1 auto; }
  h1 { font-size: 1.8rem; }
  h2 { font-size: 1.5rem; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
  }
  html { scroll-behavior: auto; }
}