:root {
  --bg: #0a0a0a;
  --surface: #141414;
  --text: #f5f5f5;
  --muted: #888;
  --accent: #ffffff;
  --border: rgba(255, 255, 255, 0.12);
  --radius: 16px;
  --max-width: 720px;
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  line-height: 1.65;
  min-height: 100vh;
}

a {
  color: var(--text);
  text-decoration: underline;
  text-underline-offset: 3px;
}

a:hover {
  opacity: 0.85;
}

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 48px 24px 80px;
}

header {
  text-align: center;
  margin-bottom: 48px;
}

.logo {
  font-size: 2rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 8px;
}

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

nav {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 12px;
  margin-top: 24px;
}

nav a {
  text-decoration: none;
  font-size: 0.875rem;
  color: var(--muted);
  padding: 8px 16px;
  border: 1px solid var(--border);
  border-radius: 999px;
  transition: color 0.2s, border-color 0.2s;
}

nav a:hover {
  color: var(--text);
  border-color: rgba(255, 255, 255, 0.3);
  opacity: 1;
}

.lang-switch {
  margin-top: 12px;
  font-size: 0.8125rem;
}

.lang-switch a {
  text-decoration: none;
  color: var(--muted);
}

.lang-switch a:hover {
  color: var(--text);
}

.lang-switch span {
  color: var(--muted);
  margin: 0 8px;
}

.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px;
  margin-bottom: 20px;
}

.card h2 {
  font-size: 1.125rem;
  font-weight: 600;
  margin-bottom: 16px;
}

.card h3 {
  font-size: 0.95rem;
  font-weight: 600;
  margin: 20px 0 8px;
  color: var(--muted);
}

.card p,
.card li {
  color: rgba(245, 245, 245, 0.88);
  font-size: 0.9375rem;
}

.card ul,
.card ol {
  padding-left: 1.25rem;
  margin-top: 8px;
}

.card li + li {
  margin-top: 6px;
}

.lang-block {
  margin-bottom: 28px;
}

.lang-block:last-child {
  margin-bottom: 0;
}

.lang-label {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--muted);
  margin-bottom: 12px;
}

.copy-box {
  background: #0d0d0d;
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 16px;
  font-size: 0.875rem;
  line-height: 1.6;
  white-space: pre-wrap;
  word-break: break-word;
  color: rgba(245, 245, 245, 0.9);
  margin-top: 8px;
}

.meta-note {
  font-size: 0.8125rem;
  color: var(--muted);
  margin-top: 8px;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 14px 28px;
  background: var(--accent);
  color: #000;
  font-weight: 600;
  font-size: 1rem;
  border-radius: 999px;
  text-decoration: none;
  border: none;
  cursor: pointer;
  transition: transform 0.15s, opacity 0.15s;
}

.btn:hover {
  opacity: 0.92;
  transform: scale(1.02);
}

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

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 12px;
  margin-top: 32px;
}

footer {
  text-align: center;
  margin-top: 48px;
  padding-top: 24px;
  border-top: 1px solid var(--border);
  font-size: 0.8125rem;
  color: var(--muted);
}

.feature-grid {
  display: grid;
  gap: 12px;
  margin-top: 12px;
}

.feature-item {
  padding: 16px;
  background: #0d0d0d;
  border-radius: 12px;
  border: 1px solid var(--border);
}

.feature-item strong {
  display: block;
  margin-bottom: 4px;
}

.updated {
  font-size: 0.8125rem;
  color: var(--muted);
  margin-bottom: 24px;
}

@media (max-width: 480px) {
  .container {
    padding: 32px 20px 64px;
  }

  .logo {
    font-size: 1.625rem;
  }
}