/* ==========================================================================
   China Travel Cheatsheet - Clean Modern CSS
   Optimized for mobile-first readability, fast load & zero bloat
   ========================================================================== */

:root {
  --primary: #dc2626;      /* 醒目的中国红强调色 */
  --primary-hover: #b91c1c;
  --bg: #f9fafb;
  --surface: #ffffff;
  --text-main: #111827;
  --text-muted: #4b5563;
  --border: #e5e7eb;
  --border-strong: #111827;
  --accent-green: #059669;
  --accent-red: #e11d48;
  --accent-blue: #2563eb;
  --radius: 12px;
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  background-color: var(--bg);
  color: var(--text-main);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

/* Header & Navigation */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--border);
  padding: 14px 24px;
}

.header-inner {
  max-width: 1120px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.logo {
  font-weight: 800;
  font-size: 1.25rem;
  color: var(--text-main);
  text-decoration: none;
  display: flex;
  align-items: center;
  gap: 8px;
}

.logo span {
  color: var(--primary);
}

.nav-links {
  display: flex;
  gap: 20px;
  list-style: none;
  align-items: center;
}

.nav-links a {
  text-decoration: none;
  color: var(--text-muted);
  font-size: 0.95rem;
  font-weight: 500;
  transition: color 0.15s ease;
}

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

/* Hero Section */
.hero {
  max-width: 1120px;
  margin: 48px auto 36px auto;
  padding: 0 24px;
  text-align: center;
}

.hero-tag {
  display: inline-block;
  padding: 4px 12px;
  background: #fee2e2;
  color: #991b1b;
  font-size: 0.825rem;
  font-weight: 700;
  border-radius: 9999px;
  margin-bottom: 16px;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.hero h1 {
  font-size: 2.75rem;
  font-weight: 900;
  letter-spacing: -0.025em;
  line-height: 1.2;
  margin-bottom: 16px;
}

.hero p {
  font-size: 1.15rem;
  color: var(--text-muted);
  max-width: 720px;
  margin: 0 auto 28px auto;
}

/* Main Container */
.container {
  max-width: 1120px;
  margin: 0 auto;
  padding: 0 24px 64px 24px;
}

/* Section Header */
.section-title-wrap {
  margin: 56px 0 24px 0;
}

.section-title {
  font-size: 1.75rem;
  font-weight: 800;
  display: flex;
  align-items: center;
  gap: 10px;
}

.section-subtitle {
  color: var(--text-muted);
  font-size: 1rem;
  margin-top: 6px;
}

/* Section 1: Checklist */
.checklist-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  box-shadow: var(--shadow-sm);
}

.checklist-grid {
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.check-item {
  display: flex;
  align-items: flex-start;
  gap: 14px;
  padding: 14px 16px;
  border-radius: 8px;
  background: #fdfdfd;
  border: 1px solid #f1f5f9;
  transition: all 0.15s ease;
}

.check-item:hover {
  border-color: #cbd5e1;
}

.check-item input[type="checkbox"] {
  width: 20px;
  height: 20px;
  margin-top: 3px;
  cursor: pointer;
  accent-color: var(--primary);
}

.check-item.done {
  opacity: 0.55;
  background: #f8fafc;
}

.check-item.done .check-title {
  text-decoration: line-through;
}

.check-content {
  flex: 1;
}

.check-title {
  font-weight: 700;
  font-size: 1.05rem;
  margin-bottom: 4px;
}

.check-desc {
  font-size: 0.925rem;
  color: var(--text-muted);
}

.badge-tag {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 700;
  padding: 2px 8px;
  border-radius: 4px;
  margin-right: 6px;
}

.badge-red { background: #ffe4e6; color: #be123c; }
.badge-blue { background: #dbeafe; color: #1e40af; }
.badge-green { background: #d1fae5; color: #065f46; }

/* Section 2: Survival Cards (Multi-Language) */
.lang-control-bar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 12px;
  background: #f1f5f9;
  padding: 12px 18px;
  border-radius: 8px;
  margin-bottom: 24px;
}

.lang-control-bar label {
  font-weight: 700;
  font-size: 0.9rem;
}

.lang-select {
  padding: 6px 14px;
  border-radius: 6px;
  border: 1px solid #cbd5e1;
  font-weight: 600;
  background: #fff;
  cursor: pointer;
}

.cards-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 20px;
}

.survival-card {
  background: var(--surface);
  border: 2px solid var(--border-strong);
  border-radius: 14px;
  padding: 24px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  box-shadow: 4px 4px 0px rgba(0, 0, 0, 0.9);
  transition: transform 0.15s ease, box-shadow 0.15s ease;
}

.survival-card:hover {
  transform: translateY(-2px);
  box-shadow: 6px 6px 0px rgba(0, 0, 0, 0.9);
}

.card-header-badge {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 14px;
  border-bottom: 1px dashed var(--border);
  padding-bottom: 8px;
}

.card-category {
  font-weight: 800;
  font-size: 0.8rem;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  color: var(--primary);
}

.card-zh {
  font-size: 1.45rem;
  font-weight: 900;
  color: #000000;
  line-height: 1.45;
  margin-bottom: 16px;
  background: #fffbeb;
  padding: 10px 14px;
  border-radius: 8px;
  border-left: 4px solid #f59e0b;
}

.card-sub-wrap {
  margin-bottom: 18px;
}

.card-sub {
  font-size: 0.95rem;
  color: #374151;
  font-weight: 500;
  line-height: 1.45;
}

.export-btn {
  width: 100%;
  padding: 10px;
  border-radius: 8px;
  border: 1px solid var(--border-strong);
  background: #ffffff;
  color: var(--text-main);
  font-weight: 700;
  font-size: 0.9rem;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  transition: background 0.15s ease;
}

.export-btn:hover {
  background: #f3f4f6;
}

/* Section 3: Itineraries */
.itinerary-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 24px;
}

.itinerary-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  box-shadow: var(--shadow-sm);
  display: flex;
  flex-direction: column;
}

.itinerary-days {
  font-size: 0.825rem;
  font-weight: 800;
  color: var(--primary);
  text-transform: uppercase;
}

.itinerary-title {
  font-size: 1.35rem;
  font-weight: 800;
  margin: 6px 0 12px 0;
}

.itinerary-route {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 6px;
  font-weight: 700;
  font-size: 0.95rem;
  color: #1e293b;
  background: #f8fafc;
  padding: 8px 12px;
  border-radius: 6px;
  margin-bottom: 14px;
}

.route-arrow {
  color: #94a3b8;
}

.itinerary-points {
  list-style: none;
  font-size: 0.925rem;
  color: var(--text-muted);
  display: flex;
  flex-direction: column;
  gap: 8px;
  margin-bottom: 18px;
  flex: 1;
}

.itinerary-points li strong {
  color: var(--text-main);
}

/* Section 4: Keep or Skip Matrix */
.matrix-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
}

@media (max-width: 768px) {
  .matrix-grid {
    grid-template-columns: 1fr;
  }
}

.matrix-col {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
}

.matrix-header {
  font-weight: 800;
  font-size: 1.15rem;
  margin-bottom: 16px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.matrix-items {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.matrix-item {
  border-bottom: 1px solid var(--border);
  padding-bottom: 12px;
}

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

.matrix-item-title {
  font-weight: 700;
  margin-bottom: 4px;
}

.matrix-item-desc {
  font-size: 0.9rem;
  color: var(--text-muted);
}

.matrix-item-tip {
  display: block;
  font-size: 0.85rem;
  color: var(--accent-green);
  font-weight: 600;
  margin-top: 4px;
}

/* Section 5: Toolkit & Affiliates */
.tools-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 16px;
}

.tool-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px;
  text-decoration: none;
  color: inherit;
  transition: all 0.15s ease;
  display: flex;
  flex-direction: column;
}

.tool-card:hover {
  border-color: var(--border-strong);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.tool-name {
  font-weight: 800;
  font-size: 1.1rem;
  margin-bottom: 4px;
}

.tool-category {
  font-size: 0.75rem;
  font-weight: 700;
  color: var(--primary);
  text-transform: uppercase;
  margin-bottom: 8px;
}

.tool-desc {
  font-size: 0.875rem;
  color: var(--text-muted);
  flex: 1;
}

.tool-cta {
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--accent-blue);
  margin-top: 12px;
}

/* Footer */
.site-footer {
  border-top: 1px solid var(--border);
  background: #fff;
  padding: 40px 24px;
  text-align: center;
  color: var(--text-muted);
  font-size: 0.9rem;
}