:root {
  --chestnut: #7f3f2d;
  --chestnut-dark: #4b211b;
  --cream: #fff8ee;
  --paper: #fffdf9;
  --gold: #e4a13a;
  --teal: #2d7772;
  --ink: #2b2622;
  --muted: #746a63;
  --line: #eaded1;
  --shadow: 0 16px 40px rgba(80, 43, 28, .1);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  color: var(--ink);
  background: var(--cream);
  font-family: "Microsoft YaHei", "PingFang SC", Arial, sans-serif;
  line-height: 1.75;
}
a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }
.container { width: min(1120px, calc(100% - 40px)); margin: 0 auto; }
.topbar {
  position: sticky; top: 0; z-index: 20;
  background: rgba(255, 253, 249, .94);
  backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--line);
}
.nav { height: 74px; display: flex; align-items: center; justify-content: space-between; gap: 20px; }
.brand { display: inline-flex; align-items: center; gap: 10px; font-weight: 800; letter-spacing: .03em; color: var(--chestnut-dark); }
.brand img { width: 40px; height: 40px; border-radius: 12px; box-shadow: 0 5px 14px rgba(127,63,45,.2); }
.brand span { font-size: 19px; }
.nav-links { display: flex; align-items: center; gap: 26px; color: var(--muted); font-size: 14px; }
.nav-links a { transition: color .2s ease; }
.nav-links a:hover, .nav-links a.active { color: var(--chestnut); }
.nav-download { background: var(--chestnut); color: #fff; padding: 9px 16px; border-radius: 10px; font-weight: 700; }
.nav-toggle { display: none; border: 0; background: none; color: var(--chestnut-dark); font-size: 26px; }
.hero { padding: 76px 0 52px; overflow: hidden; }
.hero-grid { display: grid; grid-template-columns: 1.1fr .9fr; align-items: center; gap: 66px; }
.eyebrow { color: var(--teal); font-size: 13px; font-weight: 800; letter-spacing: .16em; text-transform: uppercase; }
h1, h2, h3 { margin: 0; line-height: 1.25; color: var(--chestnut-dark); }
h1 { margin-top: 14px; font-size: clamp(38px, 6vw, 66px); letter-spacing: -.04em; }
.hero-copy > p { max-width: 580px; margin: 22px 0 0; color: var(--muted); font-size: 17px; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 30px; }
.btn { display: inline-flex; align-items: center; justify-content: center; gap: 8px; border-radius: 11px; padding: 12px 20px; font-weight: 800; font-size: 15px; border: 1px solid transparent; transition: transform .2s ease, box-shadow .2s ease; }
.btn:hover { transform: translateY(-2px); box-shadow: 0 10px 24px rgba(75,33,27,.16); }
.btn-primary { background: var(--chestnut); color: #fff; }
.btn-ghost { background: #fff; border-color: var(--line); color: var(--chestnut-dark); }
.hero-note { margin-top: 18px; color: var(--muted); font-size: 13px; }
.hero-visual { position: relative; min-height: 390px; }
.hero-visual::before { content: ""; position: absolute; inset: 26px 20px 0 20px; background: #f2dfc4; border-radius: 38% 62% 48% 52% / 42% 42% 58% 58%; transform: rotate(-8deg); }
.phone { position: relative; width: min(282px, 72%); margin: auto; padding: 9px; border-radius: 28px; background: #25201e; box-shadow: 0 28px 50px rgba(64,32,24,.3); transform: rotate(5deg); }
.phone img { border-radius: 21px; aspect-ratio: 3/4; object-fit: cover; }
.phone::after { content: "栗子漫画"; position: absolute; top: 15px; left: 50%; transform: translateX(-50%); background: rgba(255,255,255,.86); color: var(--chestnut-dark); border-radius: 20px; padding: 1px 10px; font-size: 10px; font-weight: 800; }
.section { padding: 76px 0; }
.section.alt { background: var(--paper); border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.section-head { display: flex; align-items: end; justify-content: space-between; gap: 20px; margin-bottom: 28px; }
.section-head h2 { font-size: 34px; }
.section-head p { max-width: 490px; color: var(--muted); margin: 0; }
.feature-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
.feature-card { padding: 24px; border: 1px solid var(--line); border-radius: 16px; background: var(--paper); box-shadow: 0 8px 20px rgba(80,43,28,.04); }
.feature-card:nth-child(2) { background: #f7eee4; }
.feature-card:nth-child(3) { background: #edf5f1; }
.feature-icon { width: 42px; height: 42px; display: grid; place-items: center; border-radius: 13px; background: #f6d8a8; color: var(--chestnut-dark); font-size: 20px; margin-bottom: 18px; }
.feature-card:nth-child(3) .feature-icon { background: #b9d9d3; }
.feature-card h3 { font-size: 19px; margin-bottom: 8px; }
.feature-card p { margin: 0; color: var(--muted); font-size: 14px; }
.screens { display: grid; grid-template-columns: repeat(4, 1fr); gap: 18px; align-items: end; }
.screen-card { padding: 10px; border-radius: 18px; background: #f1e5d8; border: 1px solid var(--line); }
.screen-card:nth-child(2), .screen-card:nth-child(4) { transform: translateY(24px); background: #e3efeb; }
.screen-card img { width: 100%; max-width: 400px; aspect-ratio: 3 / 4; object-fit: cover; border-radius: 12px; }
.screen-card figcaption { padding: 10px 4px 2px; color: var(--muted); font-size: 13px; }
.stats { display: grid; grid-template-columns: repeat(4, 1fr); gap: 12px; margin-top: 32px; }
.stat { padding: 18px; border-left: 3px solid var(--gold); background: #fff; border-radius: 0 12px 12px 0; }
.stat strong { display: block; color: var(--chestnut); font-size: 27px; }
.stat span { color: var(--muted); font-size: 13px; }
.split { display: grid; grid-template-columns: .85fr 1.15fr; gap: 50px; align-items: start; }
.split-copy p { color: var(--muted); }
.link-list { display: grid; gap: 12px; }
.link-card { display: flex; align-items: center; justify-content: space-between; gap: 16px; padding: 18px 20px; border: 1px solid var(--line); border-radius: 13px; background: #fff; }
.link-card small { color: var(--muted); display: block; margin-top: 3px; }
.arrow { color: var(--chestnut); font-size: 20px; }
.quote-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
.quote { margin: 0; padding: 24px; border-radius: 16px; background: #fff; border: 1px solid var(--line); }
.quote p { margin: 0 0 16px; font-size: 15px; }
.quote cite { color: var(--muted); font-size: 13px; font-style: normal; }
.cta { background: var(--chestnut-dark); color: #fff; padding: 54px 0; }
.cta-inner { display: flex; align-items: center; justify-content: space-between; gap: 24px; }
.cta h2 { color: #fff7e8; font-size: 31px; }
.cta p { color: #e8d6c8; margin: 8px 0 0; }
.cta .btn-primary { background: var(--gold); color: var(--chestnut-dark); }
.page-hero { padding: 64px 0 40px; background: #f3e5d6; border-bottom: 1px solid var(--line); }
.page-hero h1 { font-size: clamp(34px, 5vw, 52px); }
.page-hero p { max-width: 700px; color: var(--muted); margin: 16px 0 0; }
.article { padding: 54px 0 76px; }
.article-layout { display: grid; grid-template-columns: 1fr 280px; gap: 52px; align-items: start; }
.article-main { max-width: 760px; }
.article-main h2 { margin: 38px 0 14px; font-size: 27px; }
.article-main h3 { margin: 26px 0 8px; font-size: 20px; }
.article-main p { margin: 0 0 16px; color: #514841; }
.article-main ul, .article-main ol { margin: 0 0 18px; padding-left: 22px; color: #514841; }
.article-main li { margin: 6px 0; }
.side-card { position: sticky; top: 98px; padding: 22px; border-radius: 15px; background: #fff; border: 1px solid var(--line); }
.side-card h3 { font-size: 18px; margin-bottom: 10px; }
.side-card a { display: block; padding: 8px 0; color: var(--muted); border-bottom: 1px dashed var(--line); font-size: 14px; }
.side-card a:last-child { border-bottom: 0; }
.faq-list { display: grid; gap: 10px; }
details { padding: 18px 20px; background: #fff; border: 1px solid var(--line); border-radius: 12px; }
summary { cursor: pointer; font-weight: 800; color: var(--chestnut-dark); }
details p { margin: 12px 0 0; color: var(--muted); }
footer { padding: 34px 0 26px; background: #281b18; color: #d9c6ba; }
.footer-grid { display: flex; align-items: start; justify-content: space-between; gap: 30px; }
footer .brand { color: #fff3e5; }
footer .brand img { box-shadow: none; }
footer p { margin: 8px 0 0; max-width: 610px; font-size: 13px; line-height: 1.7; }
.footer-links { display: flex; gap: 18px; font-size: 13px; white-space: nowrap; }
.copyright { padding-top: 24px; margin-top: 24px; border-top: 1px solid rgba(255,255,255,.13); color: #a99488; font-size: 12px; }
@media (max-width: 820px) {
  .container { width: min(100% - 28px, 680px); }
  .nav { height: 64px; }
  .nav-toggle { display: block; }
  .nav-links { display: none; position: absolute; top: 64px; left: 0; right: 0; padding: 14px; background: #fffdf9; border-bottom: 1px solid var(--line); flex-direction: column; gap: 12px; }
  .nav-links.open { display: flex; }
  .hero { padding-top: 46px; }
  .hero-grid, .split, .article-layout { grid-template-columns: 1fr; gap: 28px; }
  .hero-visual { min-height: 330px; order: -1; }
  .feature-grid, .quote-grid { grid-template-columns: 1fr; }
  .screens { grid-template-columns: repeat(2, 1fr); gap: 12px; }
  .screen-card:nth-child(2), .screen-card:nth-child(4) { transform: none; }
  .stats { grid-template-columns: repeat(2, 1fr); }
  .cta-inner, .footer-grid { flex-direction: column; align-items: flex-start; }
  .side-card { position: static; }
}
@media (max-width: 460px) {
  h1 { font-size: 40px; }
  .section { padding: 56px 0; }
  .section-head { display: block; }
  .section-head p { margin-top: 12px; }
  .screens { grid-template-columns: 1fr 1fr; }
  .footer-links { flex-wrap: wrap; }
}