:root {
  --blue-1: #0A63D8;
  --blue-2: #3D9BFF;
  --ink: #1C1C1E;
  --ink-soft: #48484A;
  --bg: #F4F6FB;
  --card: #FFFFFF;
  --line: rgba(60, 60, 67, 0.12);
  --red: #E8341F;
  --green: #1F9E4A;
  --radius: 20px;
  --max: 880px;
}

@media (prefers-color-scheme: dark) {
  :root {
    --ink: #F2F2F7;
    --ink-soft: #C7C7CC;
    --bg: #0B0E14;
    --card: #161B24;
    --line: rgba(255, 255, 255, 0.10);
  }
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro TC", "PingFang TC",
    "Helvetica Neue", "Segoe UI", "Noto Sans TC", sans-serif;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--blue-1); text-decoration: none; }
a:hover { text-decoration: underline; }

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

.topnav {
  position: sticky;
  top: 0;
  z-index: 10;
  backdrop-filter: saturate(180%) blur(16px);
  background: color-mix(in srgb, var(--bg) 78%, transparent);
  border-bottom: 1px solid var(--line);
}

.topnav .wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 60px;
}

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

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

.navlinks { display: flex; gap: 22px; font-size: 15px; }
.navlinks a { color: var(--ink-soft); }

.hero {
  padding: 64px 0 48px;
  text-align: center;
}

.hero .icon {
  width: 104px;
  height: 104px;
  border-radius: 24px;
  box-shadow: 0 12px 30px rgba(10, 99, 216, 0.28);
  margin-bottom: 24px;
}

.hero h1 {
  font-size: clamp(28px, 5vw, 40px);
  margin: 0 0 12px;
  letter-spacing: -0.02em;
}

.hero p.tagline {
  font-size: clamp(16px, 2.6vw, 19px);
  color: var(--ink-soft);
  max-width: 620px;
  margin: 0 auto 28px;
}

.pill {
  display: inline-block;
  padding: 6px 14px;
  border-radius: 999px;
  background: linear-gradient(135deg, var(--blue-1), var(--blue-2));
  color: #fff;
  font-size: 13px;
  font-weight: 600;
  margin-bottom: 18px;
}

.store-row {
  display: flex;
  gap: 12px;
  justify-content: center;
  flex-wrap: wrap;
  margin-top: 8px;
}

.store-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 22px;
  border-radius: 14px;
  background: var(--ink);
  color: var(--bg);
  font-weight: 600;
  font-size: 15px;
  opacity: 0.5;
  cursor: default;
}

.store-btn small { display: block; font-weight: 400; font-size: 11px; opacity: 0.85; }

section { padding: 40px 0; }

.section-title {
  text-align: center;
  margin: 0 0 8px;
  font-size: clamp(22px, 3.6vw, 28px);
  letter-spacing: -0.01em;
}

.section-sub {
  text-align: center;
  color: var(--ink-soft);
  margin: 0 auto 32px;
  max-width: 560px;
  font-size: 15px;
}

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 16px;
}

.card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 22px;
}

.card .emoji {
  font-size: 26px;
  width: 48px;
  height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 14px;
  background: linear-gradient(135deg, rgba(10,99,216,0.14), rgba(61,155,255,0.14));
  margin-bottom: 14px;
}

.card h3 { margin: 0 0 6px; font-size: 17px; }
.card p { margin: 0; color: var(--ink-soft); font-size: 14px; }

.mock {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 20px 22px;
  max-width: 360px;
  margin: 0 auto;
}

.mock .row {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  padding: 10px 0;
  border-bottom: 1px solid var(--line);
  font-size: 15px;
}
.mock .row:last-child { border-bottom: none; }
.mock .row .name { color: var(--ink-soft); }
.mock .row .price { font-weight: 700; font-size: 17px; }
.mock .up { color: var(--red); font-size: 12px; margin-left: 6px; }
.mock .down { color: var(--green); font-size: 12px; margin-left: 6px; }
.mock .caption {
  text-align: center;
  font-size: 12px;
  color: var(--ink-soft);
  margin-top: 12px;
}

.sources {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  justify-content: center;
}
.sources span {
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 8px 16px;
  font-size: 13px;
  color: var(--ink-soft);
  background: var(--card);
}

.cta {
  text-align: center;
  background: linear-gradient(135deg, var(--blue-1), var(--blue-2));
  border-radius: 28px;
  padding: 48px 24px;
  color: #fff;
}
.cta h2 { margin: 0 0 10px; font-size: clamp(22px, 3.6vw, 28px); }
.cta p { margin: 0 0 22px; opacity: 0.92; }
.cta .store-btn { background: rgba(255,255,255,0.18); color: #fff; }

footer {
  border-top: 1px solid var(--line);
  padding: 32px 0 48px;
  text-align: center;
  color: var(--ink-soft);
  font-size: 13px;
}
footer a { color: var(--ink-soft); margin: 0 10px; }
footer .fbrand { color: var(--ink); font-weight: 600; margin-bottom: 8px; display: block; }

.doc h1 { font-size: clamp(26px, 4vw, 32px); margin-bottom: 4px; }
.doc .updated { color: var(--ink-soft); font-size: 13px; margin-bottom: 32px; }
.doc h2 { font-size: 19px; margin: 34px 0 10px; }
.doc p, .doc li { color: var(--ink-soft); font-size: 15px; }
.doc ul { padding-left: 20px; }
.doc table {
  width: 100%;
  border-collapse: collapse;
  margin: 12px 0;
  font-size: 14px;
}
.doc th, .doc td {
  border: 1px solid var(--line);
  padding: 8px 10px;
  text-align: left;
  color: var(--ink-soft);
}
.doc th { color: var(--ink); background: var(--card); }
.doc .box {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: 18px 20px;
  margin: 16px 0;
}