:root {
  color-scheme: light;
  --ink: #3D2817;
  --muted: #5C4A3A;
  --primary: #6B4226;
  --primary-hover: #57351E;
  --primary-active: #3D2817;
  --soft: #FDF7F0;
  --beige: #F5EFE6;
  --line: #E5DDD0;
  --paper: #FFFFFF;
  --query: #6B4226;
  --remember: #2E7D5B;
  --speak: #A84C2E;
  --space: 72px;
}
* { box-sizing: border-box; letter-spacing: 0; }
html { scroll-behavior: smooth; scroll-padding-top: 100px; }
body { margin: 0; background: var(--paper); color: var(--ink); font-family: Arial, "PingFang SC", "Microsoft YaHei", system-ui, sans-serif; font-size: 16px; line-height: 1.75; -webkit-font-smoothing: antialiased; }
a { color: inherit; text-decoration: none; }
button { font: inherit; color: inherit; cursor: pointer; }
img { max-width: 100%; }
button, a { -webkit-tap-highlight-color: transparent; }
button:focus-visible, a:focus-visible, [tabindex="0"]:focus-visible { outline: 3px solid var(--primary); outline-offset: 5px; }
.container { width: min(1160px, calc(100% - 64px)); margin-inline: auto; }
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip-path: inset(50%); white-space: nowrap; border: 0; }
.skip-link { position: fixed; left: 20px; top: -100px; padding: 10px 16px; background: var(--paper); border: 1px solid var(--primary); border-radius: 6px; z-index: 50; }
.skip-link:focus { top: 12px; }
.site-header { position: sticky; top: 0; z-index: 20; border-bottom: 1px solid var(--line); background: var(--paper); }
.header-inner { min-height: 80px; display: flex; align-items: center; gap: 32px; }
.brand { display: inline-flex; align-items: center; gap: 12px; font-size: 18px; font-weight: 750; white-space: nowrap; }
.brand > img { display: block; border-radius: 8px; flex: none; }
.brand-en { margin-left: 5px; font-size: 14px; font-weight: 500; color: var(--muted); }
.site-nav { display: flex; align-items: center; gap: 28px; margin-left: auto; }
.site-nav a { padding-block: 12px; font-size: 14px; color: var(--muted); transition: color 180ms ease; }
.site-nav a:hover { color: var(--primary); }
.header-actions { display: flex; align-items: center; gap: 10px; }
.button { display: inline-flex; justify-content: center; align-items: center; gap: 12px; min-height: 52px; padding: 12px 22px; border: 1px solid var(--primary); border-radius: 6px; background: var(--primary); color: #FFFFFF; font-size: 15px; font-weight: 650; white-space: nowrap; transition: background 180ms ease, border-color 180ms ease; }
.button:hover { background: var(--primary-hover); border-color: var(--primary-hover); }
.button:active { background: var(--primary-active); }
.button .icon { display: block; flex: none; filter: brightness(0) invert(1); }
.button-secondary { background: var(--paper); color: var(--ink); border-color: var(--line); }
.button-secondary:hover { background: var(--soft); border-color: var(--ink); }
.button-secondary .icon { filter: none; }
.button-small { min-height: 44px; padding: 8px 16px; font-size: 14px; }
.menu-button { display: none; width: 44px; height: 44px; border: 1px solid var(--line); border-radius: 6px; padding: 9px; background: var(--paper); }
.menu-button img { display: block; }
.hero { position: relative; background: var(--soft); padding-block: 56px 64px; }
.hero-content { text-align: center; }
.eyebrow { color: var(--primary); font-size: 13px; font-weight: 650; margin: 0 0 14px; }
.hero h1 { margin: 0; font-size: 72px; line-height: 1.16; font-weight: 800; }
.hero-en { display: block; margin-top: 8px; font-size: 18px; line-height: 1.5; font-weight: 500; color: var(--muted); }
.slogan { display: flex; align-items: center; justify-content: center; gap: 12px; margin-top: 18px; font-size: 26px; font-weight: 750; line-height: 1.5; }
.slogan > span { white-space: nowrap; }
.slogan .query { color: var(--query); }
.slogan .remember { color: var(--remember); }
.slogan .speak { color: var(--speak); }
.slogan-dot { color: var(--muted); font-size: 18px; }
.hero-description { color: var(--muted); font-size: 16px; line-height: 1.8; margin: 16px auto 20px; max-width: 530px; text-wrap: balance; }
.hero-actions { display: flex; align-items: center; justify-content: center; gap: 12px; }
.hero-platforms { font-size: 12px; color: var(--muted); margin: 8px 0 0; }
.section { padding-block: var(--space); scroll-margin-top: 20px; }
.features-section { padding-top: 40px; }
.section-heading { text-align: center; max-width: 760px; margin: 0 auto 44px; }
.section-heading h2, .about h2 { font-size: 40px; line-height: 1.4; font-weight: 750; margin: 0 0 16px; text-wrap: balance; }
.section-heading > p:last-child { margin: 0; color: var(--muted); text-wrap: balance; }
.feature-showcase { display: grid; grid-template-columns: 1.05fr 1fr; gap: 100px; align-items: center; max-width: 1000px; margin-inline: auto; }
.features { display: flex; flex-direction: column; gap: 0; }
.feature-option { display: flex; align-items: flex-start; gap: 18px; width: 100%; padding: 22px 12px; border: 0; border-bottom: 1px solid var(--line); background: transparent; text-align: left; border-radius: 0; transition: background 180ms ease; }
.feature-option:first-child { border-top: 1px solid var(--line); }
.feature-option:hover { background: var(--soft); }
.feature-option.is-active { background: var(--beige); border-left: 3px solid var(--primary); padding-left: 9px; }
.feature-icon { display: block; flex: none; padding-top: 6px; }
.feature-icon img { display: block; }
.feature-copy { display: block; min-width: 0; }
.feature-number { display: block; font-size: 11px; font-weight: 650; color: var(--muted); margin-bottom: 3px; }
.feature-title { display: block; font-size: 21px; font-weight: 700; margin-bottom: 7px; }
.feature-description { display: block; color: var(--muted); font-size: 14px; line-height: 1.85; text-wrap: pretty; }
.feature-arrow { display: block; flex: none; margin-top: 8px; opacity: 0; }
.is-active .feature-arrow { opacity: 1; }
.feature-preview { margin: 0; min-width: 0; }
.preview-description { display: none; }
.screen-stage { width: 294px; max-width: 100%; height: 584px; margin-inline: auto; }
.screen-image { display: block; width: 100%; height: 100%; object-fit: contain; background: var(--soft); border-radius: 8px; }
.feature-preview figcaption { display: flex; align-items: center; justify-content: center; gap: 8px; font-size: 13px; color: var(--muted); margin-top: 16px; min-height: 44px; text-align: center; }
.feature-preview figcaption a { display: inline-flex; align-items: center; justify-content: center; width: 44px; height: 44px; flex: none; border-radius: 6px; }
.feature-preview figcaption a:hover { background: var(--soft); }
.course-preview { display: flex; align-items: center; justify-content: center; gap: 12px; padding-top: 28px; margin: 40px 0 0; border-top: 1px solid var(--line); font-size: 14px; color: var(--muted); }
.course-preview img { flex: none; }
.download-section { background: var(--soft); }
.download-app-icon { display: block; margin: 0 auto 20px; border-radius: 8px; }
.store { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; max-width: 870px; margin-inline: auto; }
.store-option { display: flex; flex-direction: column; align-items: flex-start; justify-content: flex-start; padding: 30px; background: var(--paper); border: 1px solid var(--line); border-radius: 8px; }
.store-copy h3 { font-size: 22px; margin: 0 0 4px; }
.store-copy p { font-size: 14px; margin: 0; color: var(--muted); }
.store-link { display: inline-flex; min-height: 44px; padding: 11px; margin: 20px 0 0 -11px; border-radius: 6px; }
.app-store-badge { display: block; width: auto; height: 44px; }
.platform-heading { display: flex; align-items: center; gap: 14px; }
.platform-icon { display: block; width: 40px; height: 32px; object-fit: contain; flex: none; }
.copy-control { display: none; margin-top: 24px; min-width: 174px; }
.js .copy-control { display: inline-flex; }
.market-list { color: var(--muted); font-size: 12px; margin: 16px 0 0; }
.copy-status { min-height: 24px; max-width: 870px; margin: 8px auto 0; font-size: 13px; color: var(--primary); }
.mini-entry { display: flex; justify-content: space-between; align-items: center; max-width: 870px; margin: 24px auto 0; padding-top: 32px; border-top: 1px solid var(--line); gap: 24px; }
.mini-entry .eyebrow { font-size: 12px; margin-bottom: 6px; }
.mini-entry h3 { margin: 0 0 8px; font-size: 20px; }
.mini-entry p:last-child { color: var(--muted); font-size: 14px; margin: 0; }
.qr-card { flex: none; line-height: 0; }
.qr-card img { width: 112px; height: 112px; object-fit: contain; display: block; }
.about-grid { display: grid; grid-template-columns: 1fr 0.9fr; gap: 112px; }
.about > p:not(.eyebrow) { color: var(--muted); max-width: 510px; margin: 0 0 20px; }
.about .company-location { font-size: 13px; }
.contact { align-self: center; padding-left: 32px; border-left: 1px solid var(--line); }
.contact h3 { margin: 0 0 16px; font-size: 25px; line-height: 1.5; }
.contact > p:not(.eyebrow) { color: var(--muted); margin: 0 0 22px; font-size: 15px; }
.contact-email { display: flex; align-items: center; justify-content: space-between; gap: 12px; padding-block: 12px; border-bottom: 1px solid var(--line); font-size: 18px; font-weight: 650; overflow-wrap: anywhere; }
.contact-email img { flex: none; }
.contact-privacy { display: inline-flex; align-items: center; gap: 6px; min-height: 44px; margin-top: 8px; font-size: 13px; color: var(--muted); }
.site-footer { padding-block: 32px; background: var(--soft); border-top: 1px solid var(--line); }
.footer-inner { display: grid; grid-template-columns: 1fr auto; gap: 22px 40px; align-items: center; }
.footer-brand { font-size: 16px; }
.footer-links { display: flex; align-items: center; gap: 24px; font-size: 13px; color: var(--muted); }
.footer-links a { padding-block: 12px; }
.footer-legal { display: flex; justify-content: space-between; flex-wrap: wrap; gap: 12px; grid-column: 1 / -1; font-size: 12px; color: var(--muted); border-top: 1px solid var(--line); padding-top: 18px; }
.footer-legal a { display: inline-flex; align-items: center; min-height: 44px; }
@media (max-width: 1000px) {
  .header-inner { gap: 20px; }
  .site-nav { gap: 18px; }
  .brand-en { display: none; }
  .feature-showcase { gap: 40px; }
  .about-grid { gap: 50px; }
}
@media (max-width: 760px) {
  :root { --space: 48px; }
  .container { width: calc(100% - 40px); }
  .header-inner { min-height: 68px; gap: 10px; justify-content: space-between; }
  .brand { gap: 8px; font-size: 16px; }
  .brand > img { width: 36px; height: 36px; }
  .site-nav { display: none; position: absolute; top: 100%; left: 0; right: 0; margin: 0; padding: 12px 20px; background: var(--paper); border-bottom: 1px solid var(--line); }
  .site-nav[data-open="true"] { display: flex; flex-direction: column; align-items: stretch; gap: 0; }
  .site-nav a { min-height: 44px; }
  .js .menu-button { display: block; }
  .header-actions { gap: 8px; }
  .button-small { min-height: 44px; padding-inline: 12px; font-size: 12px; }
  .button-small .icon { display: none; }
  .hero { padding-block: 36px 40px; }
  .hero .eyebrow { font-size: 12px; margin-bottom: 10px; }
  .hero h1 { font-size: 52px; }
  .hero-en { font-size: 16px; margin-top: 6px; }
  .slogan { font-size: 24px; gap: 9px; margin-top: 16px; }
  .slogan-dot { font-size: 14px; }
  .hero-description { font-size: 14px; margin: 14px 0 18px; }
  .hero-actions { gap: 10px; }
  .hero-actions .button { padding-inline: 14px; font-size: 13px; min-height: 48px; gap: 8px; }
  .hero-platforms { font-size: 11px; margin-top: 12px; }
  .section-heading { margin-bottom: 28px; }
  .section-heading h2, .about h2 { font-size: 30px; }
  .section-heading > p:last-child { font-size: 14px; }
  .feature-showcase { grid-template-columns: 1fr; gap: 28px; }
  .features { display: grid; grid-template-columns: 1fr 1fr; gap: 0; }
  .feature-option { display: flex; align-items: center; gap: 8px; padding: 16px 12px; min-height: 64px; border: 1px solid var(--line); margin: 0; }
  .feature-option:first-child { border-top: 1px solid var(--line); }
  .feature-option[data-feature="home"] { grid-column: 1 / -1; }
  .feature-option:not(:first-child) { border-top: 0; }
  .feature-option:nth-child(3), .feature-option:nth-child(5) { border-left: 0; }
  .feature-option.is-active { border-left: 3px solid var(--primary); padding-left: 10px; }
  .feature-icon { padding: 0; margin: 0; }
  .feature-icon img { width: 20px; height: 20px; }
  .feature-number { display: none; }
  .feature-title { font-size: 15px; margin: 0; }
  .feature-description { display: none; }
  .preview-description { display: block; min-height: 72px; font-size: 14px; line-height: 1.7; margin: 0 auto 18px; color: var(--muted); text-wrap: pretty; }
  .feature-arrow { display: none; }
  .screen-stage { height: 540px; width: 272px; }
  .course-preview { font-size: 13px; text-wrap: balance; margin-top: 24px; padding-top: 24px; }
  .store { grid-template-columns: 1fr; gap: 16px; }
  .store-option { padding: 24px; }
  .mini-entry { gap: 16px; padding-top: 24px; margin-top: 16px; }
  .mini-entry h3 { font-size: 18px; }
  .mini-entry .eyebrow { font-size: 11px; }
  .mini-entry p:last-child { font-size: 12px; }
  .qr-card img { width: 96px; height: 96px; }
  .about-grid { grid-template-columns: 1fr; gap: 32px; }
  .about > p:not(.eyebrow) { font-size: 14px; }
  .contact { padding: 28px 0 0; border-left: 0; border-top: 1px solid var(--line); }
  .contact h3 { font-size: 23px; }
  .contact-email { font-size: 16px; }
  .footer-inner { grid-template-columns: 1fr; gap: 16px; }
  .footer-links { flex-wrap: wrap; gap: 12px 20px; }
  .footer-legal { flex-direction: column; gap: 6px; }
}
@media (max-width: 360px) {
  .container { width: calc(100% - 32px); }
  .slogan { font-size: 21px; gap: 7px; }
  .hero-actions .button { font-size: 12px; padding-inline: 10px; }
  .hero-actions .icon { width: 16px; height: 16px; }
  .feature-title { font-size: 15px; }
  .store-option { padding: 20px; }
  .mini-entry h3 { font-size: 16px; }
  .mini-entry .eyebrow { font-size: 10px; }
}
@media (max-height: 700px) and (max-width: 760px) {
  .hero { padding-block: 24px 32px; }
  .hero h1 { font-size: 40px; }
  .hero-en { font-size: 13px; }
  .slogan { font-size: 21px; margin-top: 10px; }
  .hero-description { font-size: 13px; margin: 10px 0 12px; }
  .hero-actions .button { min-height: 44px; }
  .hero-platforms { display: none; }
}
@media (max-height: 850px) and (min-width: 761px) {
  .hero { padding-block: 36px 44px; }
  .hero h1 { font-size: 54px; }
  .hero-description { margin: 10px auto 12px; }
  .slogan { margin-top: 10px; }
}
@media (max-height: 480px) and (min-width: 761px) {
  .header-inner { min-height: 64px; }
  .hero { padding-block: 20px 28px; }
  .hero .eyebrow, .hero-en, .hero-platforms { display: none; }
  .hero h1 { font-size: 36px; }
  .slogan { font-size: 20px; margin-top: 8px; }
  .hero-description { font-size: 13px; line-height: 1.6; margin: 8px auto 10px; }
  .hero-description br { display: none; }
  .hero-actions .button { min-height: 44px; padding: 8px 16px; font-size: 13px; }
  .features-section { padding-top: 24px; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { transition: none !important; animation: none !important; }
}