:root {
  --bg: #f6f8fc;
  --surface: #ffffff;
  --text: #0f172a;
  --muted: #526079;
  --accent: #24336b;
  --line: #e5e7eb;
  --shadow: 0 14px 28px rgba(15, 23, 42, 0.08);
}
* { box-sizing: border-box; }
body {
  margin: 0;
  font-family: "Inter", system-ui, -apple-system, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.65;
}
h1, h2 {
  font-family: "Sora", "Inter", sans-serif;
  margin: 0 0 10px;
  line-height: 1.25;
  letter-spacing: -0.01em;
}
h1 { font-size: clamp(1.55rem, 3.4vw, 2rem); }
h2 { font-size: 1.08rem; margin-top: 18px; }
p, li { color: var(--muted); }
.muted { color: #64748b; font-size: 0.9rem; }
.topbar {
  position: sticky;
  top: 0;
  z-index: 30;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--line);
}
.container {
  width: min(980px, 100%);
  margin: 0 auto;
  padding: 0 20px;
}
.topbar-inner {
  min-height: 68px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
}
.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-weight: 800;
  text-decoration: none;
  color: #0f172a;
}
.brand img {
  width: 38px;
  height: 38px;
  border-radius: 10px;
  border: 1px solid var(--line);
}
.lang-selector {
  display: inline-flex;
  gap: 6px;
  padding: 4px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: #fff;
}
.lang-selector a.lang-btn {
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 36px;
  border-radius: 999px;
  padding: 6px 10px;
  font-size: 0.8rem;
  font-weight: 700;
  color: #334155;
  transition: background 0.2s ease, color 0.2s ease;
}
.lang-selector a.lang-btn:hover {
  background: rgba(36, 51, 107, 0.1);
  color: var(--accent-strong);
}
.lang-selector a.lang-btn.active {
  background: var(--accent);
  color: #fff;
}
.lang-selector a.lang-btn.active:hover {
  background: var(--accent-strong);
  color: #fff;
}
main { padding: 24px 0 56px; }
.card {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 16px;
  box-shadow: var(--shadow);
  padding: 20px;
}
ul { margin: 8px 0 0; padding-left: 18px; }
a {
  color: var(--accent);
  text-decoration: none;
  font-weight: 600;
}
a:hover { text-decoration: underline; }
.top-links {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin: 10px 0 14px;
  font-size: 0.92rem;
}
@media (max-width: 720px) {
  .container { padding: 0 12px; }
  .card { padding: 16px; }
}