:root {
  color-scheme: light;
  --ink: #20352d;
  --ink-soft: #52645d;
  --paper: #f4f1ea;
  --paper-deep: #e9e2d6;
  --card: #fffdf9;
  --green: #456e5b;
  --green-dark: #315344;
  --coral: #d97859;
  --line: rgba(32, 53, 45, 0.13);
  --shadow: 0 24px 70px rgba(49, 62, 54, 0.14);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  min-width: 320px;
  color: var(--ink);
  background: var(--paper);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}
a { color: inherit; }
.container { width: min(1160px, calc(100% - 48px)); margin-inline: auto; }

.skip-link {
  position: fixed;
  z-index: 100;
  top: 12px;
  left: 12px;
  padding: 10px 14px;
  color: #fff;
  background: var(--green-dark);
  border-radius: 10px;
  transform: translateY(-160%);
}
.skip-link:focus { transform: translateY(0); }

.site-header {
  position: relative;
  z-index: 10;
  border-bottom: 1px solid var(--line);
  background: rgba(244, 241, 234, 0.94);
}
.header-inner, .footer-inner { display: flex; align-items: center; justify-content: space-between; }
.header-inner { min-height: 78px; }
.brand {
  display: inline-flex;
  align-items: center;
  gap: 11px;
  color: var(--ink);
  font-size: 18px;
  font-weight: 760;
  letter-spacing: 0.04em;
  text-decoration: none;
}
.brand-mark {
  display: grid;
  width: 38px;
  height: 38px;
  place-items: center;
  color: #fff;
  background: var(--green);
  border-radius: 12px 12px 12px 4px;
  font-family: "STKaiti", "KaiTi", serif;
  font-size: 23px;
  font-weight: 700;
  line-height: 1;
  box-shadow: 0 7px 18px rgba(69, 110, 91, 0.24);
}
.site-nav { display: flex; gap: 32px; color: var(--ink-soft); font-size: 15px; }
.site-nav a { text-decoration: none; }
.site-nav a:hover, .site-nav a:focus-visible,
.footer-meta a:hover, .footer-meta a:focus-visible {
  color: var(--green);
  text-decoration: underline;
  text-underline-offset: 5px;
}

.hero { position: relative; overflow: hidden; padding: 96px 0 108px; }
.hero::before, .hero::after {
  position: absolute;
  content: "";
  border-radius: 999px;
  pointer-events: none;
}
.hero::before {
  top: -260px;
  right: -180px;
  width: 620px;
  height: 620px;
  background: rgba(205, 221, 207, 0.48);
}
.hero::after {
  bottom: -200px;
  left: -160px;
  width: 420px;
  height: 420px;
  background: rgba(231, 197, 172, 0.24);
}
.hero-grid {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: minmax(0, 0.88fr) minmax(520px, 1.12fr);
  gap: 62px;
  align-items: center;
}
.eyebrow {
  display: flex;
  align-items: center;
  gap: 10px;
  margin: 0 0 18px;
  color: var(--green);
  font-size: 13px;
  font-weight: 750;
  letter-spacing: 0.16em;
}
.eyebrow span { width: 26px; height: 2px; background: var(--coral); }
.hero h1 {
  margin: 0;
  font-family: "STSong", "Songti SC", serif;
  font-size: clamp(48px, 5.2vw, 72px);
  font-weight: 700;
  letter-spacing: -0.055em;
  line-height: 1.2;
  overflow-wrap: anywhere;
}
.hero-intro {
  max-width: 560px;
  margin: 28px 0 0;
  color: var(--ink-soft);
  font-size: 18px;
  line-height: 1.9;
  overflow-wrap: anywhere;
}
.hero-actions { display: flex; flex-wrap: wrap; gap: 13px; margin-top: 36px; }
.button {
  display: inline-flex;
  min-height: 48px;
  align-items: center;
  justify-content: center;
  padding: 0 22px;
  border: 1px solid transparent;
  border-radius: 999px;
  font-size: 15px;
  font-weight: 700;
  text-decoration: none;
  transition: transform 160ms ease, background-color 160ms ease, border-color 160ms ease;
}
.button:hover { transform: translateY(-2px); }
.button:focus-visible, .site-nav a:focus-visible, .brand:focus-visible, .footer-meta a:focus-visible {
  outline: 3px solid rgba(217, 120, 89, 0.5);
  outline-offset: 4px;
}
.button-primary { color: #fff; background: var(--green-dark); box-shadow: 0 12px 26px rgba(49, 83, 68, 0.22); }
.button-primary:hover { background: #243f34; }
.button-secondary { border-color: rgba(49, 83, 68, 0.25); background: rgba(255, 253, 249, 0.58); }
.button-secondary:hover { border-color: var(--green); background: var(--card); }

.product-preview { position: relative; padding: 35px 20px 28px; }
.preview-window {
  position: relative;
  display: grid;
  grid-template-columns: 31% 69%;
  min-height: 430px;
  overflow: hidden;
  border: 1px solid rgba(32, 53, 45, 0.12);
  border-radius: 26px;
  background: #f9f7f2;
  box-shadow: var(--shadow);
  transform: rotate(1.2deg);
}
.preview-sidebar { padding: 30px 18px; color: #e8f0eb; background: #29483b; }
.preview-logo {
  display: flex;
  align-items: center;
  gap: 8px;
  margin: 0 6px 30px;
  font-size: 13px;
  font-weight: 700;
}
.preview-logo span {
  display: grid;
  width: 27px;
  height: 27px;
  place-items: center;
  color: #29483b;
  background: #f3d3bc;
  border-radius: 9px 9px 9px 3px;
  font-family: "STKaiti", "KaiTi", serif;
  font-size: 17px;
}
.preview-nav-item {
  display: flex;
  align-items: center;
  gap: 10px;
  margin: 7px 0;
  padding: 10px 12px;
  border-radius: 11px;
  color: rgba(232, 240, 235, 0.68);
  font-size: 11px;
}
.preview-nav-item i { width: 8px; height: 8px; border: 1px solid currentColor; border-radius: 50%; }
.preview-nav-item.is-active { color: #fff; background: rgba(255, 255, 255, 0.12); }
.preview-nav-item.is-active i { border-color: #f3d3bc; background: #f3d3bc; }
.preview-content { padding: 38px 34px; }
.preview-heading { display: flex; align-items: flex-end; justify-content: space-between; gap: 20px; margin-bottom: 24px; }
.preview-heading small { display: block; margin-bottom: 5px; color: #7a8982; font-size: 10px; }
.preview-heading strong { font-family: "STSong", "Songti SC", serif; font-size: 25px; }
.preview-date { color: #78877f; font-size: 9px; }
.preview-card {
  padding: 23px;
  border: 1px solid rgba(32, 53, 45, 0.09);
  border-radius: 18px;
  background: #fffefa;
}
.preview-card-main { margin-bottom: 15px; background: #e6eee7; }
.preview-card-label {
  display: inline-block;
  margin-bottom: 12px;
  color: var(--green);
  font-size: 9px;
  font-weight: 700;
  letter-spacing: 0.12em;
}
.preview-card strong { display: block; font-size: 15px; }
.preview-card p { margin: 6px 0 0; color: #6c7b74; font-size: 9px; }
.preview-progress {
  display: block;
  height: 5px;
  margin-top: 20px;
  overflow: hidden;
  background: rgba(69, 110, 91, 0.14);
  border-radius: 10px;
}
.preview-progress i { display: block; width: 54%; height: 100%; background: var(--green); border-radius: inherit; }
.preview-card-row { display: grid; grid-template-columns: 1fr 1fr; gap: 15px; }
.preview-card-icon {
  display: grid;
  width: 31px;
  height: 31px;
  margin-bottom: 17px;
  place-items: center;
  border-radius: 10px;
  font-size: 11px;
  font-weight: 700;
}
.preview-card-icon.coral { color: #98543e; background: #f4dace; }
.preview-card-icon.green { color: #456e5b; background: #dce9df; }
.preview-note {
  position: absolute;
  z-index: 2;
  padding: 9px 14px;
  border: 1px solid rgba(32, 53, 45, 0.12);
  border-radius: 999px;
  color: var(--ink-soft);
  background: var(--card);
  box-shadow: 0 12px 32px rgba(49, 62, 54, 0.12);
  font-family: "STKaiti", "KaiTi", serif;
  font-size: 13px;
}
.note-one { top: 6px; right: 0; transform: rotate(5deg); }
.note-two { bottom: 0; left: 0; transform: rotate(-5deg); }

.feature-section { padding: 104px 0 118px; background: #fffdf9; }
.section-heading { max-width: 690px; }
.section-heading h2, .about-copy h2 {
  margin: 0;
  font-family: "STSong", "Songti SC", serif;
  font-size: clamp(34px, 4vw, 50px);
  letter-spacing: -0.035em;
  line-height: 1.3;
}
.section-heading > p:last-child, .about-copy > p { margin: 18px 0 0; color: var(--ink-soft); font-size: 17px; }
.feature-grid { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 18px; margin-top: 52px; }
.feature-card {
  min-height: 250px;
  padding: 28px 26px;
  border: 1px solid var(--line);
  border-radius: 22px;
  background: var(--card);
  transition: transform 180ms ease, box-shadow 180ms ease;
}
.feature-card:hover { box-shadow: 0 18px 40px rgba(49, 62, 54, 0.09); transform: translateY(-4px); }
.feature-number { color: var(--coral); font-family: Georgia, serif; font-size: 13px; font-style: italic; }
.feature-card h3 { margin: 54px 0 12px; font-family: "STSong", "Songti SC", serif; font-size: 22px; }
.feature-card p { margin: 0; color: var(--ink-soft); font-size: 14px; }

.about-section { padding: 112px 0; background: var(--green-dark); }
.about-grid {
  display: grid;
  grid-template-columns: minmax(0, 0.85fr) minmax(420px, 1.15fr);
  gap: 100px;
  align-items: start;
}
.about-copy, .about-copy .eyebrow, .about-copy > p { color: #f7f5ee; }
.about-copy .eyebrow span { background: #efb897; }
.about-copy > p { color: rgba(247, 245, 238, 0.74); }
.about-copy .release-note {
  margin-top: 25px;
  padding-left: 15px;
  border-left: 2px solid #efb897;
  font-size: 13px;
}
.product-facts {
  margin: 0;
  overflow: hidden;
  border: 1px solid rgba(255, 255, 255, 0.15);
  border-radius: 22px;
  background: rgba(255, 255, 255, 0.06);
}
.product-facts div {
  display: grid;
  grid-template-columns: 120px 1fr;
  gap: 24px;
  padding: 20px 24px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.12);
}
.product-facts div:last-child { border-bottom: 0; }
.product-facts dt { color: rgba(247, 245, 238, 0.55); font-size: 13px; }
.product-facts dd { margin: 0; color: #f7f5ee; font-size: 14px; }

.site-footer { padding: 40px 0; border-top: 1px solid var(--line); background: var(--paper-deep); }
.footer-brand .brand-mark { width: 34px; height: 34px; font-size: 20px; }
.site-footer p { margin: 9px 0 0; color: var(--ink-soft); font-size: 13px; }
.footer-meta { text-align: right; }
.footer-meta a { display: inline-block; margin-top: 6px; color: var(--ink-soft); font-size: 13px; text-decoration: none; }

.error-page { display: grid; min-height: 100vh; place-items: center; padding: 32px; }
.error-card {
  width: min(520px, 100%);
  padding: 52px 36px;
  border: 1px solid var(--line);
  border-radius: 28px;
  background: var(--card);
  box-shadow: var(--shadow);
  text-align: center;
}
.error-card .brand-mark { margin-inline: auto; }
.error-code {
  margin: 24px 0 0;
  color: var(--coral);
  font-family: Georgia, serif;
  font-size: 15px;
  font-style: italic;
  letter-spacing: 0.16em;
}
.error-card h1 { margin: 8px 0 0; font-family: "STSong", "Songti SC", serif; font-size: 34px; }
.error-card > p:not(.error-code) { margin: 14px 0 28px; color: var(--ink-soft); }

@media (max-width: 980px) {
  .hero { padding-top: 72px; }
  .hero-grid, .about-grid { grid-template-columns: 1fr; }
  .hero-grid { gap: 54px; }
  .about-grid { gap: 48px; }
  .hero-copy { max-width: 720px; }
  .product-preview { width: min(690px, 100%); margin-inline: auto; }
  .feature-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 640px) {
  .container { width: min(calc(100% - 32px), 1160px); }
  .header-inner { min-height: 68px; }
  .site-nav { display: none; }
  .hero { padding: 62px 0 76px; }
  .hero h1 { font-size: clamp(38px, 11vw, 44px); }
  .hero-intro { font-size: 16px; }
  .hero-actions { align-items: stretch; flex-direction: column; }
  .button { width: 100%; }
  .product-preview { margin-top: 6px; padding: 25px 0 22px; }
  .preview-window { grid-template-columns: 1fr; min-height: 410px; transform: none; }
  .preview-sidebar { display: flex; overflow: hidden; align-items: center; gap: 8px; padding: 14px; }
  .preview-logo { min-width: max-content; margin: 0 10px 0 0; }
  .preview-nav-item { min-width: max-content; margin: 0; }
  .preview-nav-item:not(.is-active) { display: none; }
  .preview-content { padding: 26px 20px 24px; }
  .preview-note { display: none; }
  .feature-section, .about-section { padding: 78px 0; }
  .feature-grid { grid-template-columns: 1fr; gap: 12px; margin-top: 36px; }
  .feature-card { min-height: auto; }
  .feature-card h3 { margin-top: 30px; }
  .product-facts div { grid-template-columns: 1fr; gap: 5px; }
  .footer-inner { align-items: flex-start; flex-direction: column; gap: 28px; }
  .footer-meta { text-align: left; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { scroll-behavior: auto !important; transition-duration: 0.01ms !important; }
}