:root {
  --bg-color: #ffffff;
  --text-main: #1d1d1f;
  --text-muted: #6e6e73;
  --border-color: #d2d2d7;
  --card-bg: #f5f5f7;
  --card-border: #e5e5ea;
  --accent-color: #0066cc;
  --accent-hover: #0077ed;
  --table-header-bg: #fbfbfd;
  --table-border: #e5e5ea;
  --badge-bg: #e8f2fc;
  --badge-text: #0066cc;
  --font-sans: -apple-system, BlinkMacSystemFont, "SF Pro Text", "SF Pro Display", "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg-color: #000000;
    --text-main: #f5f5f7;
    --text-muted: #86868b;
    --border-color: #38383a;
    --card-bg: #1c1c1e;
    --card-border: #2c2c2e;
    --accent-color: #2997ff;
    --accent-hover: #47a6ff;
    --table-header-bg: #1c1c1e;
    --table-border: #38383a;
    --badge-bg: #10243e;
    --badge-text: #58a6ff;
  }
}

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

body {
  font-family: var(--font-sans);
  background-color: var(--bg-color);
  color: var(--text-main);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

.container {
  max-width: 820px;
  margin: 0 auto;
  padding: 40px 24px 80px 24px;
}

/* Header & Nav */
header {
  margin-bottom: 48px;
  padding-bottom: 20px;
  border-bottom: 1px solid var(--border-color);
}

.nav-bar {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.nav-brand {
  font-size: 15px;
  font-weight: 600;
  text-decoration: none;
  color: var(--text-main);
  display: inline-flex;
  align-items: center;
  gap: 8px;
  letter-spacing: -0.01em;
}

.nav-brand svg {
  color: var(--accent-color);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 16px;
}

.nav-link {
  font-size: 14px;
  color: var(--text-muted);
  text-decoration: none;
  transition: color 0.2s;
}

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

.lang-switch {
  display: inline-flex;
  gap: 3px;
  background: var(--card-bg);
  padding: 3px;
  border-radius: 8px;
  border: 1px solid var(--card-border);
}

.lang-btn {
  background: none;
  border: none;
  padding: 4px 10px;
  font-size: 12px;
  font-weight: 500;
  border-radius: 6px;
  cursor: pointer;
  color: var(--text-muted);
  transition: all 0.2s;
}

.lang-btn.active {
  background: var(--bg-color);
  color: var(--text-main);
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.08);
}

/* Landing Hero Section */
.hero {
  text-align: center;
  padding: 60px 0 50px 0;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 13px;
  font-weight: 500;
  color: var(--badge-text);
  background: var(--badge-bg);
  padding: 6px 14px;
  border-radius: 20px;
  margin-bottom: 24px;
}

.hero h1 {
  font-size: 42px;
  font-weight: 700;
  letter-spacing: -0.03em;
  line-height: 1.2;
  margin-bottom: 18px;
}

.hero p {
  font-size: 19px;
  color: var(--text-muted);
  max-width: 600px;
  margin: 0 auto 36px auto;
  line-height: 1.5;
}

.hero-actions {
  display: flex;
  justify-content: center;
  gap: 14px;
  flex-wrap: wrap;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 24px;
  font-size: 15px;
  font-weight: 600;
  border-radius: 12px;
  text-decoration: none;
  transition: all 0.2s;
}

.btn-primary {
  background-color: var(--accent-color);
  color: #ffffff;
}

.btn-primary:hover {
  background-color: var(--accent-hover);
  transform: translateY(-1px);
}

.btn-secondary {
  background-color: var(--card-bg);
  color: var(--text-main);
  border: 1px solid var(--card-border);
}

.btn-secondary:hover {
  border-color: var(--border-color);
  background-color: var(--table-header-bg);
}

/* Features Grid */
.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 20px;
  margin: 60px 0;
}

.feature-card {
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  border-radius: 16px;
  padding: 24px;
  transition: transform 0.2s, box-shadow 0.2s;
}

.feature-card:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(0, 0, 0, 0.05);
}

.feature-icon {
  width: 40px;
  height: 40px;
  border-radius: 10px;
  background: var(--badge-bg);
  color: var(--badge-text);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 16px;
}

.feature-title {
  font-size: 18px;
  font-weight: 600;
  margin-bottom: 8px;
  letter-spacing: -0.01em;
}

.feature-desc {
  font-size: 14px;
  color: var(--text-muted);
  line-height: 1.6;
}

/* Typography for Legal Docs */
article h1 {
  font-size: 32px;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 16px;
}

article h2 {
  font-size: 22px;
  font-weight: 600;
  letter-spacing: -0.01em;
  margin-top: 40px;
  margin-bottom: 16px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--border-color);
}

article h3 {
  font-size: 17px;
  font-weight: 600;
  margin-top: 28px;
  margin-bottom: 12px;
}

article p {
  margin-bottom: 16px;
  font-size: 15px;
  color: var(--text-main);
}

article ul, article ol {
  margin-bottom: 20px;
  padding-left: 24px;
}

article li {
  margin-bottom: 8px;
  font-size: 15px;
}

article strong {
  font-weight: 600;
}

a {
  color: var(--accent-color);
  text-decoration: none;
  transition: color 0.15s;
}

a:hover {
  color: var(--accent-hover);
  text-decoration: underline;
}

/* Meta Pill Box */
.meta-box {
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  border-radius: 12px;
  padding: 16px 20px;
  margin-bottom: 32px;
  display: flex;
  flex-direction: column;
  gap: 8px;
  font-size: 14px;
  color: var(--text-muted);
}

.meta-box strong {
  color: var(--text-main);
}

/* Tables */
.table-wrapper {
  overflow-x: auto;
  margin: 24px 0;
  border: 1px solid var(--table-border);
  border-radius: 10px;
}

table {
  width: 100%;
  border-collapse: collapse;
  font-size: 14px;
  text-align: left;
}

th, td {
  padding: 12px 16px;
  border-bottom: 1px solid var(--table-border);
}

th {
  background-color: var(--table-header-bg);
  font-weight: 600;
  color: var(--text-main);
  white-space: nowrap;
}

tr:last-child td {
  border-bottom: none;
}

/* Footer */
footer {
  margin-top: 80px;
  padding-top: 32px;
  border-top: 1px solid var(--border-color);
  font-size: 13px;
  color: var(--text-muted);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
}

.footer-links {
  display: flex;
  gap: 20px;
}

.footer-links a {
  color: var(--text-muted);
  text-decoration: none;
}

.footer-links a:hover {
  color: var(--text-main);
  text-decoration: underline;
}

/* Language Visibility */
.lang-en, .lang-zh {
  display: block;
}

body.show-zh .lang-en {
  display: none !important;
}

body.show-en .lang-zh {
  display: none !important;
}

/* Print Styles */
@media print {
  body {
    background: #fff !important;
    color: #000 !important;
  }
  .lang-switch, .nav-bar, footer, .hero, .features-grid {
    display: none !important;
  }
  .container {
    max-width: 100% !important;
    padding: 0 !important;
  }
  .meta-box, .table-wrapper {
    border: 1px solid #ccc !important;
  }
}