:root {
  --primary-color: #0175c2;
  --primary-hover: #015a96;
  --bg-color: #0f172a;
  --card-bg: #1e293b;
  --text-color: #f8fafc;
  --text-muted: #94a3b8;
  --border-color: #334155;
  --font-sans: 'Inter', system-ui, -apple-system, sans-serif;
}

@media (prefers-color-scheme: light) {
  :root {
    --bg-color: #f8fafc;
    --card-bg: #ffffff;
    --text-color: #0f172a;
    --text-muted: #64748b;
    --border-color: #e2e8f0;
  }
}

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

body {
  font-family: var(--font-sans);
  background-color: var(--bg-color);
  color: var(--text-color);
  line-height: 1.6;
  padding: 2rem 1rem;
}

.container {
  max-width: 800px;
  margin: 0 auto;
  background: var(--card-bg);
  padding: 3rem;
  border-radius: 16px;
  border: 1px solid var(--border-color);
  box-shadow: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
}

.header {
  margin-bottom: 2.5rem;
  border-bottom: 2px solid var(--border-color);
  padding-bottom: 1.5rem;
  text-align: center;
}

.logo {
  font-size: 2.5rem;
  font-weight: 800;
  color: var(--primary-color);
  text-decoration: none;
  display: inline-block;
  margin-bottom: 0.5rem;
}

h1 {
  font-size: 1.8rem;
  font-weight: 700;
  margin-bottom: 0.5rem;
  line-height: 1.2;
}

.subtitle {
  color: var(--text-muted);
  font-size: 0.95rem;
}

h2 {
  font-size: 1.3rem;
  font-weight: 600;
  margin: 2rem 0 1rem 0;
  color: var(--primary-color);
  border-left: 4px solid var(--primary-color);
  padding-left: 10px;
}

p, ul {
  margin-bottom: 1.2rem;
  font-size: 1.05rem;
}

ul {
  padding-left: 1.5rem;
}

li {
  margin-bottom: 0.5rem;
}

.footer {
  margin-top: 3rem;
  border-top: 1px solid var(--border-color);
  padding-top: 1.5rem;
  text-align: center;
  font-size: 0.9rem;
  color: var(--text-muted);
}

.back-link {
  display: inline-block;
  margin-top: 1rem;
  color: var(--primary-color);
  text-decoration: none;
  font-weight: 500;
  transition: color 0.2s;
}

.back-link:hover {
  color: var(--primary-hover);
}

.lang-switcher {
  display: flex;
  justify-content: center;
  gap: 8px;
  margin-top: 1.2rem;
}

.lang-btn {
  background: var(--border-color);
  color: var(--text-color);
  border: none;
  padding: 6px 16px;
  border-radius: 20px;
  font-size: 0.85rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s ease;
}

.lang-btn.active, .lang-btn:hover {
  background: var(--primary-color);
  color: #fff;
}

.lang-content {
  display: none;
}

.lang-content.active {
  display: block;
}