:root {
  --primary: #3c6eab;
  --primary-light: #a4c6eb;
  --text: #1a1d1c;
  --text-muted: #6b7280;
  --bg: #f4f7fb;
  --card: #ffffff;
  --border: #e6ecea;
  --radius: 12px;
  --shadow: 0 4px 24px rgba(60, 110, 171, 0.08);
  --header-h: 72px;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  font-size: 16px;
  line-height: 1.65;
  color: var(--text);
  background: linear-gradient(180deg, var(--primary-light) 0%, var(--bg) 220px, var(--bg) 100%);
  min-height: 100vh;
}

a {
  color: var(--primary);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  display: flex;
  align-items: center;
  gap: 16px;
  min-height: var(--header-h);
  padding: 12px 24px;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
  box-shadow: var(--shadow);
}

.brand {
  display: flex;
  align-items: center;
  flex-shrink: 0;
}

.brand img {
  height: 36px;
  width: auto;
  display: block;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 4px;
  flex: 1;
  justify-content: center;
  flex-wrap: wrap;
}

.site-nav a {
  padding: 10px 18px;
  border-radius: 999px;
  font-size: 14px;
  font-weight: 600;
  color: var(--text-muted);
  text-decoration: none;
  transition: background 0.2s, color 0.2s;
}

.site-nav a:hover {
  color: var(--primary);
  background: rgba(60, 110, 171, 0.08);
  text-decoration: none;
}

.site-nav a.is-active {
  color: #fff;
  background: var(--primary);
}

.lang-switch {
  display: flex;
  align-items: center;
  gap: 2px;
  padding: 4px;
  background: var(--bg);
  border-radius: 999px;
  border: 1px solid var(--border);
  flex-shrink: 0;
}

.lang-switch button {
  border: none;
  background: transparent;
  color: var(--text-muted);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.04em;
  padding: 8px 12px;
  border-radius: 999px;
  cursor: pointer;
  transition: background 0.2s, color 0.2s;
}

.lang-switch button:hover {
  color: var(--primary);
}

.lang-switch button.is-active {
  background: var(--primary);
  color: #fff;
}

.page-wrap {
  max-width: 820px;
  margin: 0 auto;
  padding: 32px 20px 64px;
}

.hero-card,
.content-card {
  background: var(--card);
  border-radius: var(--radius);
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
  padding: 28px 32px;
  margin-bottom: 24px;
}

.hero-card h1,
.content-card h1 {
  margin: 0 0 8px;
  font-size: 1.75rem;
  line-height: 1.25;
  color: var(--text);
}

.subtitle,
.meta {
  margin: 0 0 20px;
  color: var(--text-muted);
  font-size: 0.95rem;
}

.content-card h2 {
  margin: 28px 0 12px;
  font-size: 1.15rem;
  color: var(--primary);
}

.content-card h2:first-child {
  margin-top: 0;
}

.content-card p {
  margin: 0 0 14px;
}

.content-card ul {
  margin: 0 0 16px;
  padding-left: 1.25rem;
}

.content-card li {
  margin-bottom: 8px;
}

.contact-box {
  display: flex;
  flex-direction: column;
  gap: 12px;
  padding: 20px;
  background: var(--bg);
  border-radius: var(--radius);
  margin-top: 8px;
}

.contact-box a {
  font-weight: 600;
}

.index-grid {
  display: grid;
  gap: 16px;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
}

.index-grid a.card-link {
  display: block;
  padding: 24px;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  text-decoration: none;
  color: inherit;
  transition: transform 0.2s, border-color 0.2s;
}

.index-grid a.card-link:hover {
  transform: translateY(-2px);
  border-color: var(--primary-light);
  text-decoration: none;
}

.index-grid a.card-link h2 {
  margin: 0 0 8px;
  font-size: 1.1rem;
  color: var(--primary);
}

.index-grid a.card-link p {
  margin: 0;
  font-size: 0.9rem;
  color: var(--text-muted);
}

.site-footer {
  text-align: center;
  padding: 24px 20px 40px;
  font-size: 0.85rem;
  color: var(--text-muted);
}

@media (max-width: 720px) {
  .site-header {
    flex-wrap: wrap;
    padding: 12px 16px;
    justify-content: space-between;
  }

  .site-nav {
    order: 3;
    width: 100%;
    justify-content: flex-start;
    overflow-x: auto;
    padding-bottom: 4px;
  }

  .site-nav a {
    white-space: nowrap;
    padding: 8px 14px;
    font-size: 13px;
  }

  .hero-card,
  .content-card {
    padding: 20px 18px;
  }
}