/* KlakChat — landing & legal pages. Monochrome / glass, matches the app. */
:root {
  --bg: #0b0b0c;
  --bg-soft: #141416;
  --surface: rgba(255, 255, 255, 0.04);
  --border: rgba(255, 255, 255, 0.10);
  --fg: #f5f5f7;
  --fg-dim: #a1a1aa;
  --fg-faint: #6b6b73;
  --accent: #ffffff;
  --radius: 18px;
  --max: 1080px;
  --font: -apple-system, BlinkMacSystemFont, "Hiragino Sans", "Hiragino Kaku Gothic ProN",
    "Noto Sans JP", "Segoe UI", Roboto, sans-serif;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font-family: var(--font);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  letter-spacing: 0.01em;
}
a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }

.wrap { width: 100%; max-width: var(--max); margin: 0 auto; padding: 0 24px; }

/* glow backdrop */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  background:
    radial-gradient(60% 50% at 50% -10%, rgba(255,255,255,0.10), transparent 70%),
    radial-gradient(40% 40% at 90% 10%, rgba(255,255,255,0.05), transparent 70%);
  pointer-events: none;
  z-index: 0;
}
main, header, footer { position: relative; z-index: 1; }

/* ---- Nav ---- */
.nav {
  position: sticky; top: 0; z-index: 10;
  backdrop-filter: blur(18px);
  -webkit-backdrop-filter: blur(18px);
  background: rgba(11, 11, 12, 0.6);
  border-bottom: 1px solid var(--border);
}
.nav .wrap { display: flex; align-items: center; justify-content: space-between; height: 64px; }
.brand { display: flex; align-items: center; gap: 12px; font-weight: 800; font-size: 18px; }
.nav-links { display: flex; gap: 26px; font-size: 14px; color: var(--fg-dim); }
.nav-links a:hover { color: var(--fg); }

/* ---- Logo mark ---- */
.logo {
  width: 38px; height: 38px; border-radius: 11px;
  background: var(--fg); color: var(--bg);
  display: grid; place-items: center;
  font-weight: 900; font-size: 22px; line-height: 1;
  box-shadow: 0 6px 24px rgba(255,255,255,0.12);
}
.logo.lg { width: 92px; height: 92px; border-radius: 24px; font-size: 54px; }

/* ---- Hero ---- */
.hero { text-align: center; padding: 90px 0 70px; }
.badge {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 6px 14px; border: 1px solid var(--border); border-radius: 999px;
  background: var(--surface); font-size: 12.5px; color: var(--fg-dim); margin-bottom: 30px;
}
.badge .dot { width: 7px; height: 7px; border-radius: 50%; background: #4ade80; }
.hero h1 {
  font-size: clamp(40px, 8vw, 76px); line-height: 1.05; margin: 0 0 20px;
  font-weight: 850; letter-spacing: -0.02em;
}
.hero p.lead { font-size: clamp(16px, 2.4vw, 20px); color: var(--fg-dim); max-width: 620px; margin: 0 auto 36px; }
.cta-row { display: flex; gap: 14px; justify-content: center; flex-wrap: wrap; }
.btn {
  display: inline-flex; align-items: center; gap: 9px;
  padding: 14px 26px; border-radius: 999px; font-weight: 700; font-size: 15px;
  border: 1px solid var(--border); transition: transform .15s ease, background .2s ease;
}
.btn:hover { transform: translateY(-2px); }
.btn.primary { background: var(--fg); color: var(--bg); border-color: var(--fg); }
.btn.ghost { background: var(--surface); color: var(--fg); }

.hero-logo { margin: 0 auto 34px; }

/* ---- Sections ---- */
section { padding: 70px 0; }
.section-title { text-align: center; margin-bottom: 50px; }
.section-title h2 { font-size: clamp(26px, 4vw, 38px); margin: 0 0 12px; letter-spacing: -0.01em; }
.section-title p { color: var(--fg-dim); margin: 0; }

.grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); gap: 18px; }
.card {
  background: var(--surface); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 28px; transition: border-color .2s ease, transform .2s ease;
}
.card:hover { border-color: rgba(255,255,255,0.22); transform: translateY(-3px); }
.card .ico {
  width: 44px; height: 44px; border-radius: 12px; display: grid; place-items: center;
  background: rgba(255,255,255,0.06); border: 1px solid var(--border); margin-bottom: 18px; font-size: 22px;
}
.card h3 { margin: 0 0 8px; font-size: 18px; }
.card p { margin: 0; color: var(--fg-dim); font-size: 14.5px; }

/* ---- CTA band ---- */
.band {
  text-align: center; border: 1px solid var(--border); border-radius: 26px;
  background: linear-gradient(180deg, rgba(255,255,255,0.06), rgba(255,255,255,0.02));
  padding: 56px 28px;
}
.band h2 { font-size: clamp(24px, 4vw, 34px); margin: 0 0 14px; }
.band p { color: var(--fg-dim); margin: 0 0 28px; }

/* ---- Footer ---- */
footer { border-top: 1px solid var(--border); padding: 46px 0; color: var(--fg-faint); font-size: 13.5px; }
footer .wrap { display: flex; flex-wrap: wrap; gap: 18px; justify-content: space-between; align-items: center; }
footer .f-links { display: flex; gap: 22px; }
footer .f-links a:hover { color: var(--fg); }

/* ---- Legal pages ---- */
.legal { padding: 60px 0 80px; }
.legal .wrap { max-width: 760px; }
.legal h1 { font-size: clamp(28px, 5vw, 40px); margin: 0 0 6px; }
.legal .updated { color: var(--fg-faint); font-size: 13px; margin-bottom: 40px; }
.legal h2 { font-size: 20px; margin: 38px 0 12px; }
.legal p, .legal li { color: var(--fg-dim); font-size: 15px; }
.legal ul { padding-left: 20px; }
.legal a.inline { color: var(--fg); text-decoration: underline; text-underline-offset: 3px; }
.note {
  border: 1px solid var(--border); background: var(--surface);
  border-radius: 12px; padding: 14px 16px; font-size: 13px; color: var(--fg-faint); margin: 24px 0;
}
.back { display: inline-block; margin-bottom: 30px; color: var(--fg-dim); font-size: 14px; }
.back:hover { color: var(--fg); }

@media (max-width: 640px) {
  .nav-links { display: none; }
  .hero { padding: 60px 0 40px; }
}