:root {
  --accent: #3370ff;
  --accent-dark: #245bdb;
  --accent-soft: rgba(51, 112, 255, 0.1);
  --bg: #ffffff;
  --bg-alt: #f5f7fb;
  --bg-grad-1: #eef3ff;
  --bg-grad-2: #f7f9fc;
  --card: #ffffff;
  --text: #1f2329;
  --text-secondary: #5a6473;
  --text-hint: #8f959e;
  --border: #e6e8ee;
  --shadow: 0 12px 40px rgba(31, 35, 41, 0.08);
  --shadow-sm: 0 4px 16px rgba(31, 35, 41, 0.06);
  --radius: 18px;
  --radius-sm: 12px;
  --maxw: 1120px;
}

@media (prefers-color-scheme: dark) {
  :root {
    --accent: #4c8bff;
    --accent-dark: #3370ff;
    --accent-soft: rgba(76, 139, 255, 0.16);
    --bg: #000000;
    --bg-alt: #0a0a0a;
    --bg-grad-1: #141414;
    --bg-grad-2: #000000;
    --card: #111111;
    --text: #f5f5f5;
    --text-secondary: #a3a3a3;
    --text-hint: #737373;
    --border: #262626;
    --shadow: 0 12px 40px rgba(0, 0, 0, 0.6);
    --shadow-sm: 0 4px 16px rgba(0, 0, 0, 0.45);
  }

  .phone-add {
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.5);
  }
}

* { margin: 0; padding: 0; box-sizing: border-box; }

html {
  scroll-behavior: smooth;
  /* 补偿 sticky 顶栏高度，避免锚点跳转后内容被遮挡 */
  scroll-padding-top: 72px;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Helvetica, Arial,
    sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

a { color: inherit; text-decoration: none; }

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

/* ---------- Header ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  backdrop-filter: saturate(180%) blur(14px);
  -webkit-backdrop-filter: saturate(180%) blur(14px);
  background: color-mix(in srgb, var(--bg) 78%, transparent);
  border-bottom: 1px solid var(--border);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: 17px;
}

.brand img { width: 30px; height: 30px; border-radius: 8px; }

.nav-links { display: flex; align-items: center; gap: 28px; }

.nav-links a {
  color: var(--text-secondary);
  font-size: 15px;
  transition: color 0.18s ease;
}

.nav-links a:hover { color: var(--accent); }

.nav-cta {
  background: var(--accent);
  color: #fff !important;
  padding: 9px 18px;
  border-radius: 999px;
  font-weight: 600;
  font-size: 14px;
  transition: background 0.18s ease, transform 0.18s ease;
}

.nav-cta:hover { background: var(--accent-dark); transform: translateY(-1px); }

/* ---------- Language switch ---------- */
.lang-switch {
  display: inline-flex;
  align-items: center;
  gap: 2px;
  padding: 3px;
  border-radius: 999px;
  background: var(--bg-alt);
  border: 1px solid var(--border);
}

.lang-switch button {
  appearance: none;
  border: none;
  background: transparent;
  color: var(--text-secondary);
  font-size: 13px;
  font-weight: 600;
  padding: 5px 10px;
  border-radius: 999px;
  cursor: pointer;
  line-height: 1;
  transition: color 0.18s ease, background 0.18s ease;
  font-family: inherit;
}

.lang-switch button:hover { color: var(--accent); }

.lang-switch button.active {
  background: var(--card);
  color: var(--accent);
  box-shadow: var(--shadow-sm);
}

/* ---------- Hero ---------- */
.hero {
  position: relative;
  padding: 96px 0 72px;
  background:
    radial-gradient(900px 420px at 80% -10%, var(--bg-grad-1), transparent 70%),
    linear-gradient(180deg, var(--bg-grad-2), var(--bg));
  overflow: hidden;
}

.hero-inner {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 56px;
  align-items: center;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: var(--accent-soft);
  color: var(--accent);
  font-size: 13px;
  font-weight: 600;
  padding: 6px 14px;
  border-radius: 999px;
  margin-bottom: 22px;
}

.hero h1 {
  font-size: clamp(34px, 5vw, 54px);
  line-height: 1.15;
  letter-spacing: -0.5px;
  margin-bottom: 18px;
}

.hero h1 .grad {
  background: linear-gradient(120deg, var(--accent), #6ba3ff);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero .slogan {
  display: flex;
  gap: 14px;
  flex-wrap: wrap;
  margin-bottom: 18px;
}

.slogan-tag {
  font-size: 20px;
  font-weight: 700;
  color: var(--text);
  display: inline-flex;
  align-items: center;
  gap: 8px;
}

.slogan-tag span { color: var(--accent); }

.hero p.lead {
  font-size: 17px;
  color: var(--text-secondary);
  max-width: 520px;
  margin-bottom: 32px;
}

/* ---------- Download buttons ---------- */
.downloads { display: flex; flex-wrap: wrap; gap: 14px; }

.dl-btn {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  padding: 13px 22px;
  border-radius: 14px;
  background: var(--card);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-sm);
  transition: transform 0.18s ease, box-shadow 0.18s ease, border-color 0.18s ease;
  min-width: 168px;
}

.dl-btn:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow);
  border-color: var(--accent);
}

.dl-btn .ico {
  width: 30px; height: 30px;
  display: flex; align-items: center; justify-content: center;
  color: var(--accent);
  flex-shrink: 0;
}

.dl-btn .ico svg { width: 28px; height: 28px; fill: currentColor; }

.dl-btn .txt { display: flex; flex-direction: column; line-height: 1.25; }
.dl-btn .txt small { font-size: 11px; color: var(--text-hint); }
.dl-btn .txt strong { font-size: 15px; font-weight: 600; }

/* ---------- Hero visual ---------- */
.hero-visual { display: flex; justify-content: center; }

.phone {
  position: relative;
  width: 280px;
  height: 560px;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 40px;
  box-shadow: var(--shadow);
  padding: 18px 14px;
  overflow: hidden;
}

.phone-screen {
  height: 100%;
  border-radius: 26px;
  background: linear-gradient(180deg, var(--bg-grad-1), var(--bg-alt));
  padding: 16px 16px 92px;
  display: flex;
  flex-direction: column;
  gap: 12px;
  overflow: hidden;
}

.phone-topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 2px 4px;
}

.phone-title {
  font-size: 16px;
  font-weight: 700;
  color: var(--text);
}

.phone-add {
  position: absolute;
  right: 28px;
  bottom: 34px;
  z-index: 2;
  width: 52px;
  height: 52px;
  border: none;
  cursor: pointer;
  border-radius: 50%;
  background: var(--accent);
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 8px 20px rgba(51, 112, 255, 0.45);
  transition: transform 0.18s ease, background 0.18s ease;
}

.phone-add:hover { background: var(--accent-dark); transform: scale(1.08); }

.phone-add svg {
  width: 26px;
  height: 26px;
  fill: none;
  stroke: currentColor;
  stroke-width: 2.4;
  stroke-linecap: round;
}

.otp-card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 14px 16px;
  box-shadow: var(--shadow-sm);
}

.otp-card .issuer { font-size: 12px; color: var(--text-hint); }
.otp-card .account { font-size: 13px; color: var(--text-secondary); margin-bottom: 6px; }
.otp-card .code {
  font-size: 26px;
  font-weight: 700;
  letter-spacing: 4px;
  color: var(--accent);
  font-variant-numeric: tabular-nums;
}
.otp-card .ring {
  float: right;
  width: 26px;
  height: 26px;
  border-radius: 50%;
  background: conic-gradient(
    from 0deg,
    var(--accent) 252deg,
    var(--accent-soft) 252deg
  );
  -webkit-mask: radial-gradient(farthest-side, transparent calc(100% - 3px), #000 calc(100% - 3px));
  mask: radial-gradient(farthest-side, transparent calc(100% - 3px), #000 calc(100% - 3px));
}

/* ---------- Sections ---------- */
.section { padding: 84px 0; }
.section.alt { background: var(--bg-alt); }

.section-head { text-align: center; max-width: 640px; margin: 0 auto 52px; }
.section-head h2 { font-size: clamp(26px, 3.5vw, 36px); margin-bottom: 14px; letter-spacing: -0.3px; }
.section-head p { color: var(--text-secondary); font-size: 16px; }

.features {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 22px;
}

.feature {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 30px 26px;
  box-shadow: var(--shadow-sm);
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.feature:hover { transform: translateY(-4px); box-shadow: var(--shadow); }

.feature .f-ico {
  width: 50px; height: 50px;
  border-radius: 14px;
  background: var(--accent-soft);
  color: var(--accent);
  display: flex; align-items: center; justify-content: center;
  margin-bottom: 18px;
}
.feature .f-ico svg { width: 26px; height: 26px; stroke: currentColor; fill: none; stroke-width: 2; }

.feature h3 { font-size: 18px; margin-bottom: 8px; }
.feature p { color: var(--text-secondary); font-size: 15px; }

/* ---------- Platforms ---------- */
.platforms {
  display: flex;
  justify-content: center;
  gap: 18px;
  flex-wrap: wrap;
}

.platform {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 32px 40px;
  box-shadow: var(--shadow-sm);
  min-width: 200px;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}
.platform:hover { transform: translateY(-4px); box-shadow: var(--shadow); }
.platform .p-ico { color: var(--accent); }
.platform .p-ico svg { width: 46px; height: 46px; fill: currentColor; }
.platform strong { font-size: 17px; }
.platform small { color: var(--text-hint); font-size: 13px; }

/* ---------- CTA ---------- */
.cta-band {
  text-align: center;
  background: linear-gradient(120deg, var(--accent), #5a93ff);
  border-radius: 28px;
  padding: 56px 32px;
  color: #fff;
  box-shadow: var(--shadow);
}
.cta-band h2 { font-size: clamp(26px, 3.5vw, 34px); margin-bottom: 12px; }
.cta-band p { opacity: 0.92; margin-bottom: 28px; font-size: 16px; }
.cta-band .downloads { justify-content: center; }
.cta-band .dl-btn {
  background: rgba(255, 255, 255, 0.14);
  border-color: rgba(255, 255, 255, 0.25);
  color: #fff;
  backdrop-filter: blur(6px);
}
.cta-band .dl-btn .ico,
.cta-band .dl-btn .txt strong { color: #fff; }
.cta-band .dl-btn .txt small { color: rgba(255, 255, 255, 0.8); }
.cta-band .dl-btn:hover { background: rgba(255, 255, 255, 0.24); border-color: #fff; }

/* ---------- Footer ---------- */
.site-footer {
  border-top: 1px solid var(--border);
  padding: 28px 0 28px;
  background: var(--bg);
}
.footer-inner {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  flex-wrap: wrap;
  gap: 12px;
}
.footer-brand { display: flex; align-items: center; gap: 10px; font-weight: 700; }
.footer-brand img { width: 28px; height: 28px; border-radius: 8px; }
.footer-links { display: flex; gap: 26px; flex-wrap: wrap; }
.footer-links a { color: var(--text-secondary); font-size: 14px; transition: color 0.18s ease; }
.footer-links a:hover { color: var(--accent); }
.footer-copy { width: 100%; color: var(--text-hint); font-size: 13px; margin-top: 4px; line-height: 1.7; }
.footer-copy a { color: var(--text-hint); transition: color 0.18s ease; }
.footer-copy a:hover { color: var(--accent); }

/* ---------- Legal pages ---------- */
.legal {
  max-width: 820px;
  margin: 0 auto;
  padding: 56px 24px 80px;
}
.legal h1 { font-size: 32px; margin-bottom: 8px; }
.legal .updated { color: var(--text-hint); font-size: 14px; margin-bottom: 36px; }
.legal h2 { font-size: 21px; margin: 36px 0 12px; }
.legal h3 { font-size: 17px; margin: 24px 0 10px; }
.legal p { color: var(--text-secondary); margin-bottom: 14px; }
.legal ul { color: var(--text-secondary); margin: 0 0 16px 22px; }
.legal li { margin-bottom: 8px; }
.legal a { color: var(--accent); }
.legal .back {
  display: inline-flex; align-items: center; gap: 6px;
  color: var(--accent); font-size: 14px; margin-bottom: 28px;
}
.legal .highlight {
  background: var(--accent-soft);
  border-left: 3px solid var(--accent);
  padding: 16px 18px;
  border-radius: 0 12px 12px 0;
  color: var(--text);
  margin-bottom: 20px;
}

/* ---------- Responsive ---------- */
@media (max-width: 860px) {
  .hero-inner { grid-template-columns: 1fr; gap: 40px; }
  .hero-visual { order: -1; }
  .nav-links a:not(.nav-cta) { display: none; }
  .features { grid-template-columns: 1fr; }
  .hero { padding: 64px 0 48px; }
  .section { padding: 60px 0; }
  .lang-switch button { padding: 5px 8px; font-size: 12px; }
}