:root {
  --bg: #0e1116;
  --bg-elev: #161b22;
  --bg-elev-2: #1f2530;
  --border: #2a3140;
  --text: #e6edf3;
  --text-dim: #8b98a8;
  --accent: #4c9aff;
  --accent-hover: #357de0;
  --ok: #2ea043;
  --err: #f85149;
  --mono: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, "Liberation Mono", monospace;
  --sans: -apple-system, BlinkMacSystemFont, "Segoe UI", system-ui, sans-serif;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.6;
  scroll-behavior: smooth;
}

a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }

/* ---------- header ---------- */
.site-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 1.1rem 2rem;
  border-bottom: 1px solid var(--border);
  background: rgba(14, 17, 22, 0.85);
  backdrop-filter: blur(8px);
  position: sticky;
  top: 0;
  z-index: 10;
}
.brand {
  font-family: var(--mono);
  font-weight: 600;
  font-size: 1.25rem;
  color: var(--text);
}
.brand:hover { text-decoration: none; }
.site-header nav {
  display: flex;
  align-items: center;
  gap: 1.5rem;
  font-size: 0.9rem;
}
.site-header nav a { color: var(--text-dim); }
.site-header nav a:hover { color: var(--text); text-decoration: none; }

.lang-switch {
  display: flex;
  border: 1px solid var(--border);
  border-radius: 6px;
  overflow: hidden;
}
.lang-switch button {
  background: transparent;
  color: var(--text-dim);
  border: 0;
  padding: 0.35rem 0.7rem;
  font: inherit;
  font-size: 0.8rem;
  cursor: pointer;
}
.lang-switch button.active { background: var(--accent); color: #fff; }

/* ---------- layout ---------- */
main { max-width: 1000px; margin: 0 auto; padding: 0 1.5rem; }
section { padding: 4rem 0; }
h2 { font-size: 1.6rem; margin: 0 0 2rem; }

/* ---------- buttons ---------- */
.btn {
  display: inline-block;
  background: var(--bg-elev-2);
  border: 1px solid var(--border);
  color: var(--text);
  padding: 0.7rem 1.4rem;
  border-radius: 8px;
  font-size: 0.95rem;
  font-weight: 500;
  cursor: pointer;
}
.btn:hover { border-color: var(--accent); text-decoration: none; }
.btn-primary { background: var(--accent); border-color: var(--accent); color: #fff; }
.btn-primary:hover { background: var(--accent-hover); border-color: var(--accent-hover); }

/* ---------- hero ---------- */
.hero { padding: 5rem 0 4rem; text-align: center; }
.kicker {
  font-family: var(--mono);
  font-size: 0.85rem;
  letter-spacing: 0.05em;
  color: var(--text-dim);
  margin: 0 0 1.25rem;
}
.kicker .dot { color: var(--accent); }
.kicker a { color: var(--text-dim); }
.hero h1 {
  font-size: 2.6rem;
  line-height: 1.15;
  margin: 0 auto 1.25rem;
  max-width: 16ch;
  letter-spacing: -0.02em;
}
.lead {
  font-size: 1.15rem;
  color: var(--text-dim);
  max-width: 60ch;
  margin: 0 auto 2rem;
}
.cta-row { display: flex; gap: 1rem; justify-content: center; flex-wrap: wrap; }
.hero-note {
  margin-top: 1.5rem;
  font-size: 0.85rem;
  color: var(--text-dim);
}

/* ---------- features ---------- */
.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 1rem;
}
.card {
  background: var(--bg-elev);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 1.4rem;
}
.card h3 { margin: 0 0 0.5rem; font-size: 1.05rem; }
.card p { margin: 0; color: var(--text-dim); font-size: 0.92rem; }

/* ---------- security ---------- */
.security { border-top: 1px solid var(--border); }
.sec-cols {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.25rem;
}
.sec-ok, .sec-no {
  background: var(--bg-elev);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 1.25rem 1.5rem;
}
.sec-ok h3 { color: var(--ok); margin-top: 0; }
.sec-no h3 { color: var(--err); margin-top: 0; }
.sec-cols ul { margin: 0; padding-left: 1.2rem; color: var(--text-dim); font-size: 0.92rem; }
.sec-cols li { margin-bottom: 0.5rem; }
.verify {
  margin-top: 1.5rem;
  font-size: 0.88rem;
  color: var(--text-dim);
}
.verify code {
  font-family: var(--mono);
  background: var(--bg-elev-2);
  padding: 0.2rem 0.5rem;
  border-radius: 4px;
  font-size: 0.85em;
}

/* ---------- footer ---------- */
.site-footer {
  border-top: 1px solid var(--border);
  background: var(--bg-elev);
  padding: 2rem;
  text-align: center;
  color: var(--text-dim);
  font-size: 0.85rem;
}
.site-footer p { margin: 0.4rem 0; }
.site-footer .clab { font-family: var(--mono); }
.site-footer .clab::before { content: "● "; font-size: 0.7em; vertical-align: middle; }
.foot-links a { color: var(--text-dim); }

@media (max-width: 680px) {
  .site-header { padding: 1rem; flex-wrap: wrap; }
  .site-header nav { gap: 1rem; font-size: 0.85rem; }
  .hero h1 { font-size: 2rem; }
  .sec-cols { grid-template-columns: 1fr; }
}