:root {
  --bg: #f7f7f5;
  --surface: #ffffff;
  --text: #1f2328;
  --muted: #5b6570;
  --line: #d5dbe1;
  --accent: #2f5d62;
  --accent-soft: #e5eef0;
  --max: 980px;
}
* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
body {
  font-family: Inter, "Segoe UI", Helvetica, Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
}
a { color: var(--accent); text-decoration: none; }
a:hover, a:focus { text-decoration: underline; }
.container { max-width: var(--max); margin: 0 auto; padding: 0 24px; }
.site-header { background: var(--surface); border-bottom: 1px solid var(--line); }
.header-row { display: flex; justify-content: space-between; gap: 24px; padding: 20px 0 16px; align-items: flex-start; }
.brand h1 { margin: 0; font-size: 1.55rem; line-height: 1.3; font-weight: 600; }
.brand .code { margin-top: 6px; color: var(--muted); font-size: 0.95rem; letter-spacing: 0.04em; }
.controls { display: flex; align-items: center; gap: 20px; }
.lang-toggle button {
  border: 1px solid var(--line); background: #fff; color: var(--text); padding: 6px 11px;
  font-size: .85rem; cursor: pointer;
}
.lang-toggle button.active { border-color: var(--accent); color: var(--accent); font-weight: 600; }
.main-nav { border-top: 1px solid var(--line); }
.main-nav .container { display: flex; gap: 18px; flex-wrap: wrap; padding: 10px 24px; }
.main-nav a { color: var(--text); font-size: 0.95rem; }
main { padding: 40px 0 56px; }
section { background: var(--surface); border: 1px solid var(--line); padding: 30px; margin-bottom: 20px; }
.hero p.lead { font-size: 1.2rem; margin: 0 0 18px; line-height: 1.5; }
.btn {
  display: inline-block; border: 1px solid var(--accent); background: var(--accent); color: #fff;
  padding: 10px 15px; font-weight: 600;
}
.btn.secondary { background: #fff; color: var(--accent); }
h2 { margin: 0 0 14px; font-size: 1.25rem; }
h3 { margin: 18px 0 8px; font-size: 1.05rem; }
p { margin: 0 0 12px; }
ul, ol { margin: 0 0 10px 20px; }
li { margin-bottom: 8px; }
.muted { color: var(--muted); }
.preview-list li { margin-bottom: 12px; }
.site-footer {
  border-top: 1px solid var(--line); padding: 28px 0 40px; color: var(--muted); font-size: .95rem;
}
.footer-line { margin: 0 0 8px; }
.lang { display: none; }
.lang.active { display: block; }
.small-note { font-size: .92rem; color: var(--muted); }
@media (max-width: 860px) {
  .header-row { flex-direction: column; gap: 14px; }
  .controls { justify-content: space-between; width: 100%; }
  section { padding: 22px; }
  .brand h1 { font-size: 1.32rem; }
  .hero p.lead { font-size: 1.07rem; }
}