:root {
  --yc-orange: #c64b22;
  --yc-orange-dark: #ac3711;
  --yc-ink: #182b42;
  --yc-blue: #254c78;
  --yc-muted: #536477;
  --yc-paper: #fff;
  --yc-border: #dce3eb;
  --bs-body-font-family: "Segoe UI", "Microsoft YaHei", "PingFang SC", sans-serif;
  --bs-body-color: var(--yc-ink);
  --bs-body-bg: #fff;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 100px; }
body { margin: 0; color: var(--yc-ink); background: #fff; font: 16px/1.8 var(--bs-body-font-family); -webkit-font-smoothing: antialiased; }
a { color: inherit; text-decoration: none; }
a:hover { color: var(--yc-orange-dark); }
button, input, select, textarea { font: inherit; }
button, a { touch-action: manipulation; }
a:focus-visible, button:focus-visible, summary:focus-visible { outline: 2px solid var(--yc-orange); outline-offset: 5px; }
h1, h2, h3, p { margin: 0; }
h1, h2, h3 { font-weight: 650; line-height: 1.4; letter-spacing: -.015em; }
h2 { font-size: 34px; }
h3 { font-size: 26px; }
svg.icon { width: 21px; height: 21px; stroke: currentColor; stroke-width: 1.6; fill: none; stroke-linecap: round; stroke-linejoin: round; flex-shrink: 0; }
.icon-library { position: absolute; width: 0; height: 0; overflow: hidden; }
.container { width: 100%; max-width: 1224px; padding-inline: 40px; margin-inline: auto; }
.section { padding-block: 72px; }
.eyebrow { display: block; color: var(--yc-muted); font-size: 13px; font-weight: 500; letter-spacing: .08em; margin-bottom: 18px; }
.orange-text { color: var(--yc-orange-dark); }
.skip-link { position: fixed; z-index: 100; top: 8px; left: 8px; padding: 10px 20px; background: white; transform: translateY(-150%); }
.skip-link:focus { transform: none; }
.site-header { height: 86px; background: #fff; border-top: 3px solid var(--yc-ink); border-bottom: 1px solid var(--yc-border); position: sticky; top: 0; z-index: 50; }
.nav-inner { height: 100%; display: flex; align-items: center; justify-content: space-between; gap: 30px; }
.brand { display: inline-flex; align-items: center; gap: 12px; flex-shrink: 0; color: var(--yc-ink); }
.brand > img { display: block; width: 44px; height: 44px; }
.brand-wordmark { display: flex; flex-direction: column; gap: 5px; white-space: nowrap; }
.brand-title { font-size: 26px; font-weight: 750; letter-spacing: .055em; line-height: 1.12; }
.brand-tagline { display: flex; justify-content: space-between; gap: 10px; font-size: 9px; font-weight: 600; letter-spacing: .18em; line-height: 1; color: var(--yc-muted); }
.brand-tagline > span:last-child { margin-right: -.18em; }
.primary-nav { display: flex; align-items: center; gap: 30px; font-size: 14px; }
.primary-nav > a { padding-block: 12px; }
.primary-nav > a.active, .primary-nav > a[aria-current=page] { color: var(--yc-orange-dark); }
.primary-nav > a.active { text-decoration: underline; text-underline-offset: 9px; text-decoration-thickness: 2px; }
.primary-nav > a.nav-contact { display: flex; align-items: center; gap: 18px; border: 1px solid var(--yc-border); padding: 9px 16px; border-radius: 2px; }
.nav-contact .icon { width: 16px; }
.menu-toggle { display: none; }
.yc-btn { display: inline-flex; align-items: center; justify-content: center; gap: 28px; padding: 13px 22px; min-height: 48px; border: 1px solid transparent; border-radius: 2px; font-size: 14px; font-weight: 600; line-height: 1.6; cursor: pointer; transition: background .15s, border-color .15s; box-shadow: none; }
.yc-btn-primary { background: var(--yc-orange); color: #fff; }
.yc-btn-primary:hover { background: var(--yc-orange-dark); color: white; }
.yc-btn:disabled { opacity: .65; cursor: wait; }
.text-link { display: inline-flex; align-items: center; gap: 15px; padding-block: 8px; color: var(--yc-blue); font-size: 14px; font-weight: 600; }
.text-link:hover { text-decoration: underline; text-underline-offset: 5px; }
.text-link .icon { width: 18px; }
.home-intro { background: #fff; border-bottom: 1px solid var(--yc-border); }
.intro-grid { display: grid; grid-template-columns: 1.35fr 1fr; gap: 70px; padding-block: 58px; align-items: center; }
.intro-copy h1 { font-size: clamp(36px, 3.4vw, 46px); font-weight: 600; line-height: 1.5; letter-spacing: -.025em; }
.intro-copy .eyebrow { color: var(--yc-blue); }
.intro-description { color: var(--yc-muted); margin: 25px 0 29px; font-size: 16px; }
.intro-note { font-size: 12px; color: var(--yc-muted); margin-top: 38px; }
.product-directory { border-left: 1px solid var(--yc-border); padding-left: 38px; align-self: center; }
.directory-heading { display: flex; justify-content: space-between; padding: 0 0 15px; font-size: 13px; font-weight: 600; border-bottom: 2px solid var(--yc-ink); }
.directory-heading span:last-child { color: var(--yc-muted); font-size: 11px; }
.product-directory > a { display: grid; grid-template-columns: 28px 1fr 20px; align-items: center; gap: 15px; padding: 15px 0; border-bottom: 1px solid var(--yc-border); }
.directory-number { font: 12px/1.5 monospace; color: var(--yc-blue); }
.product-directory strong { font-size: 18px; font-weight: 600; }
.product-directory small { display: block; font-size: 12px; color: var(--yc-muted); margin-top: 2px; }
.product-directory > a:hover strong { text-decoration: underline; text-underline-offset: 5px; }
.product-directory > a .icon { width: 17px; }
.product-directory > p { font-size: 11px; margin-top: 17px; color: var(--yc-muted); }
.section-heading { display: flex; justify-content: space-between; align-items: end; gap: 30px; margin-bottom: 44px; }
.section-heading h2 { font-weight: 600; }
.section-heading > p { font-size: 14px; color: var(--yc-muted); }
.product-feature { display: grid; grid-template-columns: 1fr 1.1fr; gap: 72px; align-items: center; padding: 32px 0; border-top: 1px solid var(--yc-border); }
.product-meta { display: flex; align-items: center; gap: 18px; font-size: 12px; color: var(--yc-muted); margin-bottom: 24px; }
.product-meta span:last-child { border-left: 1px solid #bdcad9; padding-left: 18px; }
.product-english { font: 12px/1.6 monospace; color: var(--yc-blue); letter-spacing: .06em; }
.product-story h3 { font-size: 31px; margin: 5px 0 18px; }
.product-story > p { color: var(--yc-muted); font-size: 15px; max-width: 400px; }
.product-points { display: flex; flex-wrap: wrap; list-style: none; padding: 0; gap: 8px 20px; font-size: 13px; margin: 22px 0; }
.product-points li::before { content: "·"; color: var(--yc-orange-dark); margin-right: 8px; font-weight: 700; }
.product-visual { min-width: 0; margin: 0; position: relative; }
.product-artwork { display: block; width: 100%; height: auto; aspect-ratio: 680 / 420; }
.product-visual figcaption { text-align: right; color: var(--yc-muted); font-size: 11px; padding-top: 5px; }
.additional-products { display: grid; grid-template-columns: 1fr 1fr; border-block: 1px solid var(--yc-border); margin-top: 12px; padding-block: 34px; }
.additional-products article { padding-right: 46px; }
.additional-products article + article { border-left: 1px solid var(--yc-border); padding-left: 46px; padding-right: 0; }
.additional-products .product-visual { margin-bottom: 24px; }
.additional-products .product-meta { margin-bottom: 14px; }
.additional-products h3 a { display: flex; align-items: center; justify-content: space-between; }
.additional-products h3 .icon { width: 18px; }
.additional-products p { color: var(--yc-muted); font-size: 14px; margin: 14px 0 17px; }
.company-section { padding-block: 56px; background: #f0f5fb; color: var(--yc-ink); border-block: 1px solid var(--yc-border); }
.company-grid, .questions-grid { display: grid; grid-template-columns: .8fr 1.2fr; gap: 100px; }
.company-section .eyebrow { color: var(--yc-blue); }
.company-section h2 { font-size: 34px; font-weight: 600; line-height: 1.55; }
.company-copy p { font-size: 15px; color: #40546c; }
.company-copy p + p { margin-top: 18px; }
.company-copy .company-lead { font-size: 20px; color: var(--yc-ink); }
.company-facts { display: flex; gap: 55px; border-top: 1px solid #c6d3e3; margin: 30px 0 0; padding-top: 22px; }
.company-facts dt { color: #536477; font-size: 12px; font-weight: 400; }
.company-facts dd { font-size: 14px; margin: 4px 0 0; }
.questions-grid > div > .text-link { margin-top: 25px; }
.questions { border-top: 1px solid var(--yc-border); }
.questions details { border-bottom: 1px solid var(--yc-border); }
.questions summary { padding: 21px 35px 21px 0; position: relative; font-weight: 600; font-size: 16px; list-style: none; cursor: pointer; }
.questions summary::-webkit-details-marker { display: none; }
.questions summary::after { content: "+"; position: absolute; right: 5px; font-size: 20px; font-weight: 400; }
.questions details[open] summary::after { content: "−"; }
.questions details p { color: var(--yc-muted); font-size: 14px; padding: 0 25px 23px 0; }
.contact-strip { background: #fff; padding-block: 34px; border-top: 2px solid var(--yc-ink); }
.contact-strip > .container { display: flex; align-items: center; justify-content: space-between; gap: 30px; }
.contact-strip h2 { font-size: 25px; }
.contact-strip p { font-size: 14px; color: var(--yc-muted); margin-top: 8px; }
.site-footer { background: #f5f8fc; border-top: 1px solid var(--yc-border); }
.footer-main { display: grid; grid-template-columns: 1.4fr 1fr .8fr .8fr; gap: 35px; padding: 55px 0 40px; }
.footer-brand .brand-title { font-size: 22px; }
.footer-brand .brand > img { width: 38px; height: 38px; }
.footer-brand p { color: var(--yc-muted); font-size: 13px; margin-top: 19px; }
.footer-company { display: block; font-size: 12px; color: var(--yc-muted); margin-top: 5px; }
.footer-links { display: flex; flex-direction: column; gap: 10px; font-size: 12px; color: var(--yc-muted); }
.footer-links > span { color: var(--yc-ink); font-size: 13px; font-weight: 600; margin-bottom: 5px; }
.footer-links a:hover { text-decoration: underline; text-underline-offset: 4px; }
.footer-location { display: flex; gap: 9px; font-size: 13px; }
.footer-location .icon { width: 17px; margin-top: 3px; }
.footer-location small { display: block; margin-top: 10px; font-size: 11px; color: var(--yc-muted); }
.footer-bottom { border-top: 1px solid var(--yc-border); padding-block: 21px; display: flex; justify-content: space-between; gap: 20px; color: var(--yc-muted); font-size: 11px; }
.footer-legal { display: flex; flex-wrap: wrap; gap: 6px 20px; }
.footer-icp { white-space: nowrap; }
.footer-icp:hover { text-decoration: underline; }
.back-to-top { position: fixed; right: 22px; bottom: 22px; width: 42px; height: 42px; border: 1px solid var(--yc-border); border-radius: 2px; background: #fff; cursor: pointer; z-index: 20; }
.back-to-top .icon { transform: rotate(-90deg); }
.back-to-top[hidden] { display: none; }
.detail-hero { background: var(--yc-paper); padding: 26px 0 65px; border-bottom: 1px solid var(--yc-border); }
.breadcrumb-link { display: inline-block; padding-block: 8px; font-size: 12px; color: var(--yc-muted); }
.breadcrumb-link span { margin-left: 10px; }
.detail-hero-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 70px; align-items: center; margin-top: 35px; }
.detail-hero h1 { font-size: 42px; }
.detail-tagline { font-size: 20px; margin-top: 17px; }
.detail-description { color: var(--yc-muted); margin-top: 17px; font-size: 15px; }
.detail-tags { display: flex; flex-wrap: wrap; gap: 18px; margin-block: 23px; font-size: 12px; color: var(--yc-muted); }
.detail-status { font-size: 13px; color: var(--yc-muted); border: 1px solid var(--yc-border); padding: 5px 12px; white-space: nowrap; }
.feature-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 40px; }
.feature-grid article { border-top: 1px solid var(--yc-border); padding-top: 20px; }
.feature-number { display: block; font: 12px/1.5 monospace; color: var(--yc-orange-dark); margin-bottom: 22px; }
.feature-grid h3 { font-size: 20px; margin-bottom: 13px; }
.feature-grid p { color: var(--yc-muted); font-size: 14px; }
.product-note { display: flex; gap: 15px; align-items: start; font-size: 13px; padding: 16px 0; border-block: 1px solid var(--yc-border); background: #fff; margin-top: 35px; color: var(--yc-muted); }
.product-note .icon { width: 18px; margin-top: 3px; }
.product-next { border-top: 1px solid var(--yc-border); padding-block: 50px; }
.product-next h2 { font-size: 26px; }
.next-products { display: grid; grid-template-columns: repeat(3, 1fr); gap: 35px; margin-top: 28px; }
.next-products > a { display: flex; align-items: center; gap: 14px; border-top: 1px solid var(--yc-border); padding-top: 20px; font-size: 15px; }
.next-products > a > .icon:last-child { margin-left: auto; width: 17px; }
.next-products small { display: block; color: var(--yc-muted); font-size: 12px; }
.contact-section { background: var(--yc-paper); }
.contact-grid { display: grid; grid-template-columns: .85fr 1.15fr; gap: 100px; align-items: start; }
.contact-copy h1 { font-size: 40px; margin-bottom: 24px; }
.contact-copy > p { color: var(--yc-muted); font-size: 15px; }
.contact-company { display: flex; gap: 15px; border-top: 1px solid var(--yc-border); padding-top: 26px; margin-top: 42px; }
.contact-company-icon { padding-top: 3px; }
.contact-company strong { display: block; font-size: 15px; font-weight: 600; }
.contact-company span:not(.contact-company-icon) { display: block; color: var(--yc-muted); font-size: 13px; }
.contact-tip { display: flex; flex-wrap: wrap; gap: 15px; font-size: 11px; color: var(--yc-muted); margin-top: 28px; }
.contact-form-panel { padding: 30px; background: #fff; border: 1px solid var(--yc-border); border-top: 3px solid var(--yc-blue); }
.form-title { display: flex; justify-content: space-between; align-items: center; gap: 15px; margin-bottom: 27px; }
.form-title h2 { font-size: 23px; }
.form-title > span { font-size: 11px; color: var(--yc-muted); }
.form-two-cols { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; }
.field { margin-bottom: 22px; min-width: 0; }
.field label { display: block; font-size: 14px; margin-bottom: 8px; }
.field label > span { color: var(--yc-orange-dark); }
.field input, .field select, .field textarea { width: 100%; border: 1px solid #aab9ca; border-radius: 2px; padding: 11px 12px; color: var(--yc-ink); background: #fff; font-size: 15px; line-height: 1.5; }
.field input::placeholder, .field textarea::placeholder { color: #63758a; }
.field input:focus, .field select:focus, .field textarea:focus { outline: 2px solid var(--yc-orange); outline-offset: 2px; }
.field [aria-invalid=true] { border-color: #a12c1d; }
.field textarea { min-height: 145px; resize: vertical; }
.field small { display: block; margin-top: 8px; font-size: 12px; color: var(--yc-muted); }
.consent-row { display: flex; align-items: start; gap: 10px; font-size: 12px; color: var(--yc-muted); margin-bottom: 23px; }
.consent-row input { width: 17px; height: 17px; margin-top: 3px; flex-shrink: 0; accent-color: var(--yc-orange); }
.consent-row a { text-decoration: underline; text-underline-offset: 3px; color: var(--yc-orange-dark); }
.form-submit { width: 100%; }
.form-note { color: var(--yc-muted); font-size: 11px; margin-top: 13px; }
.form-errors { border-left: 3px solid #a12c1d; padding: 13px 17px; background: #fff3ee; color: #8b2519; margin-bottom: 25px; font-size: 13px; }
.form-errors a { text-decoration: underline; }
.success-section { text-align: center; padding-block: 85px; background: var(--yc-paper); }
.success-icon { display: inline-flex; padding: 16px; border: 1px solid #a8c2b9; color: #2c6955; border-radius: 50%; margin-bottom: 25px; }
.success-section h1 { font-size: 36px; margin-bottom: 22px; }
.success-section p { color: var(--yc-muted); font-size: 15px; }
.reference-box { background: #fff; border: 1px solid var(--yc-border); padding: 15px; max-width: 430px; margin: 28px auto; }
.reference-box span { display: block; font-size: 12px; color: var(--yc-muted); }
.reference-box code { font-size: 13px; color: var(--yc-ink); overflow-wrap: anywhere; }
.success-actions { display: flex; align-items: center; justify-content: center; flex-wrap: wrap; gap: 25px; }
.prose-container { max-width: 850px; }
.privacy-section h1 { font-size: 35px; margin-bottom: 18px; }
.privacy-section h2 { font-size: 22px; margin: 32px 0 12px; }
.privacy-section p { color: var(--yc-muted); font-size: 15px; }
.privacy-date { margin-bottom: 25px; font-size: 12px !important; }
.privacy-section .text-link { margin-top: 30px; }
@media (max-width: 1050px) {
  .primary-nav { gap: 20px; font-size: 13px; }
  .intro-grid { gap: 45px; grid-template-columns: 1.2fr 1fr; }
  .intro-copy h1 { font-size: 38px; }
  .product-feature, .detail-hero-grid { gap: 35px; }
  .company-grid, .questions-grid, .contact-grid { gap: 50px; }
  .site-footer { background: #f5f8fc; border-top: 1px solid var(--yc-border); }
.footer-main { grid-template-columns: 1.2fr 1fr .8fr; }
  .footer-location { grid-column: 1 / -1; }
  .footer-location small { display: inline; margin-left: 15px; }
}
@media (max-width: 800px) {
  .container { padding-inline: 24px; }
  .site-header { height: 76px; }
  .brand-title { font-size: 23px; }
  .brand > img { width: 38px; height: 38px; }
  .brand-tagline { font-size: 8px; }
  .menu-toggle { display: flex; flex-direction: column; justify-content: center; align-items: center; gap: 6px; width: 44px; height: 44px; border: 1px solid var(--yc-border); border-radius: 2px; background: white; }
  .menu-toggle span { display: block; height: 1px; width: 19px; background: var(--yc-ink); }
  .menu-toggle[aria-expanded=true] span:first-child { transform: translateY(3.5px) rotate(45deg); }
  .menu-toggle[aria-expanded=true] span:last-child { transform: translateY(-3.5px) rotate(-45deg); }
  .primary-nav { display: none; position: absolute; top: 75px; left: 0; right: 0; background: #fff; padding: 12px 24px 24px; border-bottom: 1px solid var(--yc-border); flex-direction: column; align-items: stretch; gap: 0; font-size: 15px; }
  .primary-nav.is-open { display: flex; }
  .primary-nav > a { padding-block: 12px; }
  .primary-nav > a.nav-contact { margin-top: 12px; justify-content: space-between; }
  .intro-grid { gap: 35px; padding-block: 48px; }
  .intro-copy h1 { font-size: 30px; }
  .intro-description { font-size: 14px; }
  .intro-description br { display: none; }
  .intro-note { font-size: 11px; }
  .directory-heading span:last-child { display: none; }
  .product-directory strong { font-size: 16px; }
  .section { padding-block: 60px; }
  .product-feature { grid-template-columns: 1fr 1fr; gap: 25px; }
  .product-story h3 { font-size: 27px; }
  .company-grid, .questions-grid { gap: 35px; grid-template-columns: .8fr 1.2fr; }
  .company-facts { gap: 25px; flex-wrap: wrap; }
  .detail-hero-grid, .contact-grid { grid-template-columns: 1fr; gap: 35px; }
  .detail-visual { max-width: 600px; width: 100%; }
  .feature-grid { gap: 22px; }
  .next-products { gap: 20px; }
}
@media (max-width: 600px) {
  h2 { font-size: 28px; }
  .container { padding-inline: 22px; }
  .intro-grid { grid-template-columns: 1fr; gap: 42px; padding-block: 40px; }
  .intro-copy h1 { font-size: clamp(30px, 7.5vw, 39px); }
  .product-directory { border-left: 0; padding-left: 0; }
  .intro-note { margin-top: 24px; }
  .product-directory > a { padding-block: 13px; }
  .directory-heading span:last-child { display: inline; }
  .section-heading { display: block; margin-bottom: 30px; }
  .section-heading h2 { font-weight: 600; }
.section-heading > p { margin-top: 17px; }
  .product-feature { grid-template-columns: 1fr; gap: 28px; padding-block: 30px; }
  .product-meta { margin-bottom: 18px; }
  .product-story h3 { font-size: 29px; }
  .product-story > p { max-width: none; }
  .product-points { margin-block: 15px; }
  .additional-products { grid-template-columns: 1fr; padding: 0; }
  .additional-products article { padding: 28px 0; }
  .additional-products article + article { padding: 28px 0; border-left: 0; border-top: 1px solid var(--yc-border); }
  .company-section { padding-block: 50px; }
  .company-grid, .questions-grid { grid-template-columns: 1fr; gap: 30px; }
  .company-section h2 { font-size: 31px; }
  .company-copy .company-lead { font-size: 18px; }
  .company-facts { gap: 35px; }
  .questions-grid > div > .text-link { margin-top: 15px; }
  .questions summary { font-size: 15px; }
  .contact-strip > .container { align-items: flex-start; flex-direction: column; gap: 22px; }
  .contact-strip h2 { font-size: 23px; }
  .site-footer { background: #f5f8fc; border-top: 1px solid var(--yc-border); }
.footer-main { grid-template-columns: 1fr 1fr; padding-block: 38px 30px; gap: 30px 20px; }
  .footer-brand { grid-column: 1 / -1; }
  .footer-bottom { display: block; font-size: 11px; }
  .footer-bottom > span:last-child { display: none; }
  .footer-location small { margin-left: 0; display: block; }
  .detail-hero { padding-bottom: 40px; }
  .detail-hero h1 { font-size: 33px; }
  .detail-hero-grid { margin-top: 25px; gap: 30px; }
  .detail-tagline { font-size: 18px; }
  .detail-status { display: inline-block; margin-top: 20px; }
  .feature-grid, .next-products { grid-template-columns: 1fr; gap: 28px; }
  .feature-number { margin-bottom: 12px; }
  .product-note { padding: 17px; }
  .contact-copy h1 { font-size: 33px; }
  .contact-company { margin-top: 25px; }
  .contact-form-panel { padding: 23px 20px; }
  .form-title { align-items: start; flex-direction: column; gap: 5px; }
  .form-two-cols { grid-template-columns: 1fr; gap: 0; }
  .field input, .field select, .field textarea { font-size: 16px; }
  .back-to-top { right: 12px; bottom: 12px; width: 38px; height: 38px; }
  .success-section { padding-block: 55px; }
  .success-section h1, .privacy-section h1 { font-size: 29px; }
}
@media (max-width: 360px) {
  .container { padding-inline: 18px; }
  .intro-copy h1 { font-size: 29px; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { transition: none !important; animation: none !important; }
}