:root {
  --ink: #153b33;
  --ink-soft: #2e554c;
  --paper: #f5f3eb;
  --white: #fbfbf8;
  --line: #cdd2cc;
  --muted: #69736e;
  --orange: #c5553f;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; color: #203b35; background: var(--white); font-family: "Microsoft YaHei", "PingFang SC", system-ui, sans-serif; }
a { color: inherit; }
img { display: block; max-width: 100%; }

.site-header { position: sticky; top: 0; z-index: 20; display: flex; align-items: center; justify-content: space-between; min-height: 72px; padding: 10px max(24px, calc((100vw - 1180px) / 2)); border-bottom: 1px solid var(--line); background: rgba(251,251,248,.96); }
.wordmark { display: flex; align-items: center; gap: 11px; text-decoration: none; }
.wordmark-icon { display: grid; place-items: center; width: 38px; height: 38px; color: var(--paper); background: var(--ink); border-radius: 3px; font-family: "Noto Serif SC", "Songti SC", SimSun, serif; }
.wordmark small, .wordmark strong { display: block; }
.wordmark small { margin-bottom: 2px; color: var(--muted); font: 600 8px Arial, sans-serif; letter-spacing: 1.5px; }
.wordmark strong { font: 700 19px "Noto Serif SC", "Songti SC", SimSun, serif; letter-spacing: 1px; }
.site-header nav { display: flex; align-items: center; gap: 24px; }
.site-header nav a { color: #52605b; font-size: 13px; text-decoration: none; }
.site-header nav a:hover { color: var(--ink); }
.site-header .nav-action { padding: 10px 14px; color: #fff; background: var(--ink); border-radius: 3px; }
.site-header .nav-action:hover { color: #fff; background: var(--ink-soft); }

main { overflow: hidden; }
.hero { display: grid; grid-template-columns: minmax(0, 1fr) 170px; gap: 70px; width: min(1180px, calc(100% - 48px)); min-height: 590px; margin: 0 auto; padding: 110px 0 80px; }
.hero-copy { max-width: 780px; }
.section-code { margin: 0 0 16px; color: #707b76; font: 600 10px Arial, sans-serif; letter-spacing: 2.3px; }
.hero h1 { margin: 0; color: var(--ink); font: 700 clamp(45px, 6.6vw, 82px)/1.13 "Noto Serif SC", "Songti SC", SimSun, serif; letter-spacing: -2px; }
.hero-lead { max-width: 660px; margin: 30px 0 0; color: #53625c; font-size: 17px; line-height: 1.9; }
.hero-actions { display: flex; align-items: center; gap: 24px; margin-top: 34px; }
.button { display: inline-flex; align-items: center; justify-content: center; min-height: 44px; padding: 0 19px; border: 1px solid var(--ink); border-radius: 3px; font-size: 14px; font-weight: 700; text-decoration: none; }
.button.primary { color: #fff; background: var(--ink); }
.button.primary:hover { background: var(--ink-soft); }
.button.secondary { color: var(--ink); background: transparent; }
.button.text-link { min-height: auto; padding: 0; border: 0; color: var(--ink); }
.hero-facts { display: flex; gap: 34px; margin: 54px 0 0; padding-top: 20px; border-top: 1px solid var(--line); }
.hero-facts div { min-width: 120px; }
.hero-facts dt { color: #8a928e; font-size: 11px; }
.hero-facts dd { margin: 5px 0 0; font-size: 14px; font-weight: 700; }
.hero-index { display: grid; grid-template-rows: auto 1fr auto; justify-items: center; padding: 8px 0; color: var(--ink); }
.hero-index span { font: 700 50px Georgia, serif; }
.hero-index i { width: 1px; height: 100%; margin: 18px 0; background: var(--line); }
.hero-index small { color: var(--muted); font-size: 11px; line-height: 1.7; text-align: center; }

.product-preview { padding: 80px max(24px, calc((100vw - 1180px) / 2)); background: #e4e7e3; border-block: 1px solid var(--line); }
.section-heading { display: flex; align-items: end; justify-content: space-between; gap: 60px; margin-bottom: 32px; }
.section-heading.compact { margin-bottom: 28px; }
.section-heading h2, .license h2 { margin: 0; color: var(--ink); font: 700 clamp(28px, 3.6vw, 46px)/1.25 "Noto Serif SC", "Songti SC", SimSun, serif; }
.section-heading > p { max-width: 470px; margin: 0; color: var(--muted); font-size: 14px; line-height: 1.8; }
.product-preview figure { margin: 0; border: 1px solid #adb5ae; background: var(--paper); }
.product-preview img { width: 100%; height: auto; }
.product-preview figcaption { padding: 11px 14px; border-top: 1px solid var(--line); color: var(--muted); font-size: 11px; }

.workflow, .capabilities, .faq { width: min(1180px, calc(100% - 48px)); margin: 0 auto; padding: 92px 0; }
.workflow ol { margin: 0; padding: 0; border-top: 1px solid var(--line); list-style: none; }
.workflow li { display: grid; grid-template-columns: 100px 1fr; gap: 30px; padding: 30px 0; border-bottom: 1px solid var(--line); }
.workflow li > span { color: var(--orange); font: 700 23px Georgia, serif; }
.workflow h3, .capability-list h3 { margin: 0 0 8px; font-size: 17px; }
.workflow p, .capability-list p { margin: 0; color: var(--muted); font-size: 14px; line-height: 1.8; }

.capabilities { padding-top: 20px; }
.capability-list { display: grid; grid-template-columns: 1fr 1fr; border-top: 1px solid var(--line); border-left: 1px solid var(--line); }
.capability-list article { display: grid; grid-template-columns: 44px 1fr; gap: 0 16px; padding: 28px; border-right: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.capability-list article > span { grid-row: 1 / span 2; color: var(--orange); font: 700 20px Georgia, serif; }

.license { display: grid; grid-template-columns: 1.25fr .75fr; gap: 80px; padding: 86px max(24px, calc((100vw - 1180px) / 2)); color: #eef3f0; background: var(--ink); }
.license .section-code { color: #9db1aa; }
.license h2 { color: #fff; }
.license-copy > p:not(.section-code) { max-width: 670px; margin: 24px 0 0; color: #c4d0cc; font-size: 15px; line-height: 1.85; }
.license-copy .license-note { padding-top: 18px; border-top: 1px solid rgba(255,255,255,.18); font-size: 12px; }
.license-actions { display: flex; flex-direction: column; align-items: stretch; justify-content: center; gap: 12px; }
.license .button.primary { color: var(--ink); border-color: #fff; background: #fff; }
.license .button.secondary { color: #fff; border-color: rgba(255,255,255,.48); }
.license-actions span, .license-actions > a:not(.button) { color: #9db1aa; font-size: 11px; text-align: center; }

.faq details { border-top: 1px solid var(--line); }
.faq details:last-child { border-bottom: 1px solid var(--line); }
.faq summary { padding: 21px 4px; color: var(--ink); cursor: pointer; font-weight: 700; }
.faq details p { max-width: 800px; margin: -5px 0 22px; color: var(--muted); font-size: 14px; line-height: 1.8; }

.site-footer { display: grid; grid-template-columns: 1fr auto 1fr; align-items: center; gap: 24px; padding: 30px max(24px, calc((100vw - 1180px) / 2)); border-top: 1px solid var(--line); background: #f2f3ef; }
.site-footer strong, .site-footer span { display: block; }
.site-footer strong { font-family: "Noto Serif SC", "Songti SC", SimSun, serif; }
.site-footer span, .site-footer p { color: var(--muted); font-size: 10px; }
.site-footer nav { display: flex; gap: 18px; }
.site-footer nav a { color: #53625c; font-size: 11px; text-decoration: none; }
.site-footer p { margin: 0; text-align: right; }

.page-shell { width: min(860px, calc(100% - 40px)); min-height: calc(100vh - 143px); margin: 0 auto; padding: 72px 0 90px; }
.page-shell.wide { width: min(1080px, calc(100% - 40px)); }
.page-heading { margin-bottom: 42px; padding-bottom: 28px; border-bottom: 1px solid var(--line); }
.page-heading h1 { margin: 0; color: var(--ink); font: 700 clamp(34px, 5vw, 58px)/1.2 "Noto Serif SC", "Songti SC", SimSun, serif; }
.page-heading p { max-width: 680px; margin: 18px 0 0; color: var(--muted); line-height: 1.8; }
.prose h2 { margin: 42px 0 12px; color: var(--ink); font: 700 23px "Noto Serif SC", "Songti SC", SimSun, serif; }
.prose h3 { margin: 28px 0 10px; color: var(--ink); font-size: 16px; }
.prose p, .prose li { color: #52605b; font-size: 14px; line-height: 1.85; }
.prose ul, .prose ol { padding-left: 22px; }
.notice { padding: 16px 18px; border-left: 3px solid var(--orange); background: #f1f2ee; color: #52605b; font-size: 13px; line-height: 1.75; }

.account-layout { display: grid; grid-template-columns: .8fr 1.2fr; gap: 64px; }
.account-intro { padding-top: 10px; }
.account-intro h1 { margin: 0; color: var(--ink); font: 700 clamp(36px, 5vw, 60px)/1.18 "Noto Serif SC", "Songti SC", SimSun, serif; }
.account-intro p { color: var(--muted); line-height: 1.8; }
.account-panel { padding: 30px; border: 1px solid var(--line); background: #fff; }
.account-panel h2 { margin: 0 0 6px; color: var(--ink); font: 700 24px "Noto Serif SC", "Songti SC", SimSun, serif; }
.account-panel > p { margin: 0 0 24px; color: var(--muted); font-size: 12px; line-height: 1.7; }
.form-group { margin-bottom: 18px; }
.form-group label { display: block; margin-bottom: 7px; color: #4f5e58; font-size: 12px; font-weight: 700; }
.form-group input { width: 100%; height: 44px; padding: 0 12px; border: 1px solid #c7cdc7; border-radius: 3px; font: inherit; outline: none; }
.form-group input:focus { border-color: #6f8b82; box-shadow: 0 0 0 3px rgba(21,59,51,.08); }
.form-row-action { display: grid; grid-template-columns: 1fr auto; gap: 10px; }
.form-row-action .button { cursor: pointer; }
.form-status { min-height: 22px; margin: 13px 0 0; color: var(--muted); font-size: 12px; line-height: 1.6; }
.form-status.error { color: #a33e32; }
.form-status.success { color: #25715f; }
.account-summary { display: grid; gap: 10px; margin-bottom: 22px; padding: 16px; border: 1px solid var(--line); background: #f5f6f2; }
.account-summary span { color: var(--muted); font-size: 11px; }
.account-summary strong { color: var(--ink); }
[hidden] { display: none !important; }

@media (max-width: 820px) {
  .site-header { position: static; align-items: flex-start; }
  .site-header nav { justify-content: flex-end; gap: 14px; flex-wrap: wrap; }
  .site-header nav a:not(.nav-action) { display: none; }
  .hero { grid-template-columns: 1fr; min-height: auto; padding: 70px 0; }
  .hero-index { display: none; }
  .hero h1 { letter-spacing: -1px; }
  .section-heading, .license { grid-template-columns: 1fr; display: grid; gap: 24px; }
  .capability-list { grid-template-columns: 1fr; }
  .site-footer { grid-template-columns: 1fr; }
  .site-footer nav { flex-wrap: wrap; }
  .site-footer p { text-align: left; }
  .account-layout { grid-template-columns: 1fr; gap: 34px; }
}

@media (max-width: 520px) {
  .site-header { padding-inline: 16px; }
  .wordmark small { display: none; }
  .hero, .workflow, .capabilities, .faq { width: calc(100% - 32px); }
  .hero { padding: 52px 0; }
  .hero h1 { font-size: 42px; }
  .hero-lead { font-size: 15px; }
  .hero-facts { gap: 15px; }
  .hero-facts div { min-width: 0; }
  .hero-actions { align-items: flex-start; flex-direction: column; }
  .product-preview, .license { padding: 62px 16px; }
  .workflow, .capabilities, .faq { padding-block: 62px; }
  .workflow li { grid-template-columns: 55px 1fr; gap: 12px; }
  .capability-list article { padding: 22px 16px; }
  .account-panel { padding: 22px 16px; }
  .form-row-action { grid-template-columns: 1fr; }
}