:root {
  --bg: #f4f7fb;
  --surface: #ffffff;
  --text: #0c1b2a;
  --muted: #5a6b7b;
  --brand: #0a72d6;
  --brand-strong: #0857a3;
  --accent: #14b8a6;
  --border: #e2e9f1;
  --shadow: 0 18px 48px -22px rgba(10, 50, 90, 0.45);
  --radius: 18px;
  --maxw: 1080px;
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans", Roboto, Helvetica, Arial, sans-serif;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0a1018;
    --surface: #131c27;
    --text: #eef3f8;
    --muted: #9fb0c0;
    --brand: #3d9bff;
    --brand-strong: #1f7fe6;
    --accent: #2dd4bf;
    --border: #23303d;
    --shadow: 0 18px 50px -20px rgba(0, 0, 0, 0.7);
  }
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  font-family: var(--font);
  color: var(--text);
  background: var(--bg);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

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

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

/* Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  background: color-mix(in srgb, var(--bg) 82%, transparent);
  backdrop-filter: saturate(180%) blur(14px);
  -webkit-backdrop-filter: saturate(180%) blur(14px);
  border-bottom: 1px solid var(--border);
}
.site-header .wrap {
  display: flex;
  align-items: center;
  gap: 16px;
  height: 64px;
}
.brand { display: flex; align-items: center; gap: 12px; font-weight: 700; color: var(--text); }
.brand:hover { text-decoration: none; }
.brand img { width: 34px; height: 34px; border-radius: 9px; }
.brand span { font-size: 1.05rem; letter-spacing: -0.01em; }
.nav { margin-left: auto; display: flex; align-items: center; gap: 22px; }
.nav a { color: var(--muted); font-weight: 600; font-size: 0.95rem; }
.nav a:hover { color: var(--text); text-decoration: none; }
.lang { position: relative; }
.lang summary {
  list-style: none; cursor: pointer; color: var(--muted); font-weight: 600;
  font-size: 0.95rem; display: inline-flex; align-items: center; gap: 6px;
}
.lang summary::-webkit-details-marker { display: none; }
.lang[open] summary { color: var(--text); }
.lang-menu {
  position: absolute; right: 0; top: calc(100% + 10px); min-width: 168px;
  background: var(--surface); border: 1px solid var(--border); border-radius: 14px;
  box-shadow: var(--shadow); padding: 6px; display: grid; gap: 2px;
}
.lang-menu a { padding: 9px 12px; border-radius: 9px; color: var(--text); font-weight: 600; font-size: 0.92rem; }
.lang-menu a:hover { background: var(--bg); text-decoration: none; }
.lang-menu a[aria-current="true"] { color: var(--brand); }

.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  background: var(--brand); color: #fff; font-weight: 600; padding: 10px 18px;
  border-radius: 999px; border: 0; cursor: pointer; transition: transform .12s ease, background .2s ease;
}
.btn:hover { background: var(--brand-strong); text-decoration: none; transform: translateY(-1px); }
.btn.btn-sm { padding: 8px 16px; font-size: 0.92rem; }
.btn[aria-disabled="true"] { background: var(--muted); cursor: default; opacity: .8; transform: none; }

/* Hero */
.hero { padding: 72px 0 40px; }
.hero .wrap { display: grid; grid-template-columns: 1.05fr 0.95fr; gap: 48px; align-items: center; }
.eyebrow {
  display: inline-block; font-size: 0.82rem; font-weight: 700; letter-spacing: 0.04em;
  text-transform: uppercase; color: var(--brand); background: color-mix(in srgb, var(--brand) 12%, transparent);
  padding: 5px 12px; border-radius: 999px; margin-bottom: 18px;
}
.hero h1 { font-size: clamp(2rem, 4.6vw, 3.1rem); line-height: 1.08; letter-spacing: -0.02em; margin: 0 0 18px; }
.hero p { font-size: 1.12rem; color: var(--muted); margin: 0 0 26px; max-width: 34ch; }
.cta { display: flex; align-items: center; gap: 16px; flex-wrap: wrap; }
.cta .note { color: var(--muted); font-size: 0.88rem; }
.hero-art { display: flex; justify-content: center; align-items: center; }
.phone {
  width: min(290px, 78vw); border-radius: 38px; padding: 10px; background: #0c1b2a;
  box-shadow: var(--shadow); border: 1px solid rgba(255, 255, 255, 0.08);
}
.phone img { width: 100%; height: auto; display: block; border-radius: 28px; }

/* Features */
.section { padding: 56px 0; }
.section h2 { font-size: clamp(1.5rem, 3vw, 2.1rem); letter-spacing: -0.02em; text-align: center; margin: 0 0 8px; }
.features { display: grid; grid-template-columns: repeat(3, 1fr); gap: 28px; margin-top: 40px; }
.feature {
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 20px; box-shadow: 0 8px 28px -20px rgba(10, 50, 90, 0.4);
}
.feature .shot {
  background: linear-gradient(160deg, color-mix(in srgb, var(--brand) 14%, var(--surface)), var(--surface));
  border-radius: 12px; padding: 16px 16px 0; text-align: center; overflow: hidden;
}
.feature .shot img {
  width: 60%; height: auto; aspect-ratio: 720 / 1564; object-fit: cover; object-position: top;
  border-radius: 14px 14px 0 0; display: inline-block; vertical-align: bottom;
  box-shadow: 0 -2px 18px -8px rgba(0, 0, 0, .4);
}
.feature h3 { margin: 18px 0 6px; font-size: 1.12rem; letter-spacing: -0.01em; }
.feature p { margin: 0; color: var(--muted); font-size: 0.96rem; }

/* Disclaimer + footer */
.disclaimer { padding: 36px 0; }
.disclaimer p { color: var(--muted); font-size: 0.85rem; text-align: center; max-width: 70ch; margin: 0 auto; }
.site-footer { border-top: 1px solid var(--border); padding: 28px 0; }
.site-footer .wrap { display: flex; align-items: center; gap: 18px; flex-wrap: wrap; color: var(--muted); font-size: 0.9rem; }
.site-footer .foot-links { display: flex; gap: 18px; margin-left: auto; }
.site-footer a { color: var(--muted); font-weight: 600; }
.site-footer a:hover { color: var(--text); }

/* Privacy / legal page */
.legal { padding: 56px 0 40px; }
.legal .wrap { max-width: 760px; }
.legal h1 { font-size: clamp(1.8rem, 3.5vw, 2.4rem); letter-spacing: -0.02em; margin: 0 0 6px; }
.legal .updated { color: var(--muted); font-size: 0.9rem; margin: 0 0 28px; }
.legal .intro { font-size: 1.08rem; }
.legal h2 { font-size: 1.2rem; margin: 30px 0 6px; letter-spacing: -0.01em; }
.legal p { color: var(--text); }
.legal section p { color: var(--muted); }
.back { display: inline-block; margin-top: 8px; font-weight: 600; }

@media (max-width: 880px) {
  .hero { padding: 48px 0 24px; }
  .hero .wrap { grid-template-columns: 1fr; gap: 36px; text-align: center; }
  .hero p { margin-left: auto; margin-right: auto; }
  .cta { justify-content: center; }
  .hero-art { order: -1; }
  .features { grid-template-columns: 1fr; }
  .nav a:not(.btn) { display: none; }
}