/* Native CSS, existing static site. Geometry: 10px controls, 16px inset media,
   22px cards. Product colors identify writing (sky) and music (apricot).
   Design variance 5 / motion intensity 3 / visual density 3. */
:root {
  color-scheme: light;
  --paper: #f8f9fb;
  --surface: #ffffff;
  --ink: #30343c;
  --muted: #68717e;
  --line: #e5e8ed;
  --accent: #a8512d;
  --accent-soft: #fff0e4;
  --radius: 22px;
  --shadow: 0 8px 24px #30384408;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 28px; }
body {
  margin: 0;
  min-height: 100dvh;
  display: flex;
  flex-direction: column;
  background: var(--paper);
  color: var(--ink);
  font-family: "Segoe UI", "Microsoft YaHei UI", "Microsoft YaHei", "PingFang SC", system-ui, sans-serif;
  -webkit-font-smoothing: antialiased;
  line-height: 1.7;
  font-size: 15px;
}
body[data-product="qinggai"] { --accent: #3b6593; --accent-soft: #eaf3fc; }
main { flex: 1; }
.status-page { padding-block: 48px; }
.status-panel { max-width: 620px; padding-block: clamp(48px, 12vh, 120px); }
.status-label { color: var(--accent); font-size: 14px; }
.status-panel h1 { font-size: clamp(26px, 4vw, 36px); margin-block: 14px 20px; }
.status-panel p { max-width: 40em; }
.status-actions { display: flex; flex-wrap: wrap; gap: 12px; margin-block: 28px; }
.status-help { font-size: 13px; }
.release-tools { display: flex; flex-wrap: wrap; align-items: center; gap: 8px 16px; margin-top: 10px; }
.release-tools .release-status { margin: 0; }
a { color: inherit; text-decoration: none; }
button, input { font: inherit; }
button { cursor: pointer; }
button:disabled { cursor: wait; }
a, button, input, summary { -webkit-tap-highlight-color: transparent; }
a:focus-visible, button:focus-visible, input:focus-visible, summary:focus-visible {
  outline: 3px solid #8cb7df;
  outline-offset: 5px;
}
img { max-width: 100%; height: auto; }
h1, h2, h3, p, figure { margin: 0; }
h1, h2, h3 { font-weight: 650; line-height: 1.4; }
h1 { letter-spacing: -.045em; }
h2 { font-size: 27px; letter-spacing: -.03em; }
p { color: var(--muted); }
[hidden] { display: none !important; }
.wrap { width: min(1120px, calc(100% - 80px)); margin-inline: auto; }
.icon { width: 20px; height: 20px; display: inline-block; flex: none; fill: currentColor; vertical-align: middle; }
.header { height: 96px; display: flex; align-items: center; justify-content: space-between; gap: 24px; border-bottom: 1px solid var(--line); }
.brand { display: inline-flex; align-items: center; gap: 13px; font-size: 21px; font-weight: 650; letter-spacing: -.04em; }
.brand-icon { width: 48px; height: 48px; object-fit: contain; }
.header nav a { display: inline-flex; align-items: center; min-height: 40px; padding: 5px 15px; color: #555e6b; font-size: 14px; border-radius: 10px; transition: background .18s; }
.header nav a:hover, .header nav a[aria-current="page"] { background: #edf0f4; color: var(--ink); }
.section-heading { display: flex; align-items: center; justify-content: space-between; gap: 24px; margin-bottom: 28px; }
.section-heading p { margin-top: 10px; font-size: 14px; }
.catalog { padding-block: 48px 64px; }
.catalog-heading { align-items: flex-end; margin-bottom: 30px; }
.title-line { display: flex; align-items: center; gap: 14px; }
.catalog-title h1 { font-size: 31px; }
.count { color: #5c6876; font-size: 13px; background: #ecf0f4; border-radius: 10px; padding: 2px 9px; font-variant-numeric: tabular-nums; }
.catalog-title p { font-size: 14px; margin-top: 8px; }
.search { width: 300px; height: 48px; padding: 0 14px; display: flex; align-items: center; gap: 10px; flex: none; background: var(--surface); border: 1px solid var(--line); border-radius: 10px; transition: border-color .18s, box-shadow .18s; }
.search:focus-within { border-color: #90b5d7; box-shadow: 0 0 0 3px #dfeefa; }
.search > .icon { width: 19px; height: 19px; color: #818a97; }
.search input { padding: 0; border: 0; outline: none; min-width: 0; width: 100%; background: none; color: var(--ink); font-size: 14px; }
.search input::placeholder { color: #707987; }
.search input::-webkit-search-cancel-button { display: none; }
.search button { display: grid; place-items: center; width: 24px; height: 28px; padding: 0; border: 0; background: none; color: #77808a; }
.tool-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 28px; }
.tool-card { display: flex; flex-direction: column; min-width: 0; padding: 28px; background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); box-shadow: var(--shadow); transition: transform .2s, border-color .2s, box-shadow .2s; }
.tool-card:hover { transform: translateY(-4px); border-color: #c8d3df; box-shadow: 0 12px 32px #3543540c; }
.card-heading { display: flex; gap: 16px; align-items: center; }
.card-heading img { width: 60px; height: 60px; object-fit: contain; flex: none; border-radius: 16px; }
.card-heading h2 { font-size: 28px; letter-spacing: -.04em; }
.card-heading > div > span { display: block; margin-top: 2px; font-size: 13px; color: var(--muted); }
.category-label { margin-left: auto; align-self: flex-start; padding: 3px 9px; border-radius: 6px; background: #ecf4fc; color: #4c7198; font-size: 11px; white-space: nowrap; }
.music-card .category-label { color: #96532c; background: #fff2e6; }
.card-summary { font-size: 14px; line-height: 1.9; margin-top: 22px; min-height: 54px; max-width: 31em; }
.card-preview { margin-block: 22px; height: 216px; border-radius: 16px; overflow: hidden; display: flex; justify-content: center; align-items: center; background: #edf4fb; }
.writing-preview img { display: block; width: 254px; border: 1px solid #dbe4ee; border-radius: 10px; box-shadow: 0 8px 20px #58718b16; }
.music-card-preview { background: #fff3e8; align-items: flex-start; }
.music-card-preview img { display: block; width: 92%; margin-top: 20px; border: 1px solid #e7ded5; border-radius: 10px 10px 0 0; box-shadow: 0 7px 20px #96663810; }
.card-footer { display: flex; justify-content: space-between; align-items: center; gap: 14px; margin-top: auto; }
.platforms { display: flex; align-items: center; flex-wrap: wrap; gap: 14px; color: #737b87; }
.platforms span { display: inline-flex; align-items: center; gap: 5px; font-size: 12px; }
.platforms .icon { width: 16px; height: 16px; }
.card-footer strong { display: inline-flex; align-items: center; gap: 9px; font-size: 13px; font-weight: 600; white-space: nowrap; color: #49698d; }
.music-card .card-footer strong { color: #a45f35; }
.card-footer strong .icon { width: 18px; height: 18px; transition: transform .18s; }
.tool-card:hover .card-footer strong .icon { transform: translate(2px, -2px); }
.search-empty { text-align: center; padding: 64px 24px; border: 1px dashed #d5dce5; border-radius: var(--radius); background: #fff; }
.search-empty > .icon { width: 32px; height: 32px; color: #98a3b0; margin-bottom: 18px; }
.search-empty h2 { font-size: 22px; }
.search-empty p { margin: 10px 0 24px; font-size: 14px; }
.button { display: inline-flex; align-items: center; justify-content: center; gap: 10px; padding: 12px 20px; min-height: 46px; border: 1px solid transparent; border-radius: 10px; font-size: 14px; font-weight: 600; white-space: nowrap; transition: background .18s, border-color .18s, transform .18s; }
.button.primary { background: var(--accent-soft); color: var(--accent); border-color: color-mix(in srgb, var(--accent) 14%, transparent); }
.button.primary:hover { background: color-mix(in srgb, var(--accent-soft) 90%, var(--accent)); }
.button.outline { background: #fff; border-color: #dce3ea; color: #545f6d; }
.button.outline:hover { background: #f0f4f8; border-color: #c9d3df; }
.button:active { transform: translateY(1px); }
.footer { margin-top: auto; border-top: 1px solid var(--line); background: #f4f6f8; }
.footer-main { padding-block: 28px 32px; display: flex; align-items: center; flex-wrap: wrap; gap: 28px; font-size: 12px; color: #69727e; }
.footer-main.footer-filing { justify-content: center; padding-top: 0; }
.copyright { white-space: nowrap; }
.footer-links { margin-left: auto; display: flex; gap: 18px; }
.footer a:hover { color: var(--ink); }
.contact-block { position: relative; display: flex; align-items: center; flex-wrap: wrap; gap: 12px; }
.feedback-label { color: #69727e; font-size: 11px; }
.email { color: #68717e; font-size: 13px; user-select: all; }
.copy-email { display: inline-flex; align-items: center; gap: 5px; padding: 4px 0; border: 0; background: transparent; color: #68717e; font-size: 12px; }
.copy-email .icon { width: 15px; height: 15px; }
.copy-email:hover { color: #313b48; }
.copy-status { position: absolute; right: 0; top: calc(100% + 2px); font-size: 11px; color: var(--accent); }
.back-link { display: inline-flex; align-items: center; gap: 8px; color: #69727e; font-size: 13px; margin-bottom: 36px; }
.back-link:hover { color: var(--ink); }
.back-link .icon { width: 17px; height: 17px; }
.product-hero { padding-block: 28px 64px; }
.product-heading { display: grid; grid-template-columns: .84fr 1.16fr; gap: 56px; align-items: center; }
.product-name { display: flex; align-items: center; gap: 16px; margin-bottom: 26px; font-size: 25px; font-weight: 650; letter-spacing: -.03em; }
.product-name img { width: 64px; height: 64px; border-radius: 16px; object-fit: contain; }
.product-name small { display: block; font-size: 12px; font-weight: 400; letter-spacing: 0; color: var(--muted); margin-top: 2px; }
.product-heading h1 { font-size: clamp(30px, 3.2vw, 42px); line-height: 1.5; }
.lead { font-size: 15px; line-height: 1.9; margin: 17px 0 27px; max-width: 27em; }
.product-meta { display: flex; flex-wrap: wrap; gap: 14px; color: #68717e; font-size: 11px; margin-top: 20px; }
.product-meta > span { display: inline-flex; align-items: center; gap: 4px; }
.product-meta .icon { width: 15px; height: 15px; }
.product-preview { background: #edf4fb; padding: 28px; border-radius: var(--radius); border: 1px solid #e2eaf3; text-align: center; }
.product-preview img { display: block; width: min(100%, 400px); margin: 0 auto; border: 1px solid #d8e1ea; border-radius: 12px; box-shadow: 0 12px 26px #617d9512; }
figcaption { margin-top: 20px; font-size: 11px; line-height: 1.7; color: #626e7b; text-align: center; }
.music-preview { background: #fff3e8; padding: 20px 20px 16px; border: 1px solid #f0e5dc; border-radius: var(--radius); overflow: hidden; }
.music-preview img { display: block; width: 100%; border: 1px solid #e6dfd9; border-radius: 12px; }
.music-preview figcaption { margin-top: 14px; color: #776454; }
.music-download-note { font-size: 12px; line-height: 1.9; margin-top: 16px; }
.section-copy p { font-size: 14px; margin-top: 12px; }
.demo-section, .use-cases { display: grid; grid-template-columns: .8fr 1.2fr; gap: 64px; align-items: start; padding-block: 48px 64px; border-top: 1px solid var(--line); }
.scenario-list { margin-top: 34px; display: grid; gap: 23px; }
.scenario-list > div { display: grid; grid-template-columns: 42px 1fr; gap: 12px; }
.scenario-list h3 { font-size: 13px; font-weight: 600; line-height: 1.85; color: #547494; }
.scenario-list p { font-size: 13px; line-height: 1.85; margin: 0; }
.tool-demo { background: #f0f4f8; padding: 26px; border: 1px solid #e4e9ef; border-radius: var(--radius); }
.demo-tabs { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 4px; margin-bottom: 26px; }
.demo-tabs button { border: 1px solid transparent; border-radius: 10px; background: transparent; color: #77828e; padding: 8px 5px; font-size: 12px; white-space: nowrap; }
.demo-tabs button:hover { background: #e6ecf3; }
.demo-tabs button[aria-pressed="true"] { background: #fff; color: #41678d; border-color: #e0e6ed; box-shadow: 0 2px 5px #54667b05; }
.example-source > span { color: #626e7b; font-size: 11px; }
.example-source p { color: #687582; font-size: 14px; line-height: 1.9; margin: 8px 0 22px; }
.result-paper { background: #fff; border: 1px solid #e0e7ee; border-radius: 16px; padding: 20px; }
.paper-heading { display: flex; align-items: center; gap: 10px; color: #68717e; font-size: 11px; }
.qinggai-word { color: #406d9b; font-weight: 650; font-size: 14px; }
.result-paper > p { min-height: 80px; white-space: pre-line; margin-top: 16px; font-size: 14px; color: #475563; line-height: 1.9; }
.paper-foot { display: flex; justify-content: space-between; gap: 12px; margin-top: 18px; color: #626e7b; font-size: 10px; }
.demo-footnote { font-size: 11px; color: #626e7b; margin-top: 16px; }
.cases-list { display: grid; }
.cases-list article { display: grid; grid-template-columns: 95px 1fr; gap: 24px; padding-block: 21px; border-bottom: 1px solid var(--line); }
.cases-list article:first-child { padding-top: 0; }
.cases-list article:last-child { border-bottom: 0; padding-bottom: 0; }
.cases-list h3 { font-size: 15px; color: #a5653e; line-height: 1.85; }
.cases-list p { font-size: 14px; line-height: 1.85; }
.download { padding-block: 44px 56px; border-top: 1px solid var(--line); }
.text-button { display: inline-flex; align-items: center; gap: 7px; background: none; color: var(--accent); border: 0; padding: 6px 0; font-size: 13px; white-space: nowrap; }
.text-button .icon { width: 17px; height: 17px; }
.text-button:hover { color: var(--ink); }
.release-status { font-size: 12px; color: #68717e; min-height: 22px; margin-bottom: 18px; }
.downloads { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 18px; }
.download-card { display: flex; flex-direction: column; align-items: flex-start; padding: 24px; background: #fff; border: 1px solid var(--line); border-radius: var(--radius); }
.download-card.recommended { border-color: #cfdeec; }
.download-os { display: flex; align-items: center; gap: 12px; }
.download-os > .icon { width: 28px; height: 28px; color: #71879c; }
.download-os h3 { font-size: 17px; letter-spacing: -.035em; }
.download-os p { font-size: 11px; margin-top: 4px; }
.release-meta { color: var(--accent); font-size: 12px; margin: 22px 0 20px; min-height: 22px; font-variant-numeric: tabular-nums; }
.download-card .button { width: 100%; margin-top: auto; padding-inline: 10px; gap: 8px; font-size: 13px; }
.download-card small { min-height: 3.8em; font-size: 11px; color: #68717e; line-height: 1.9; margin-top: 16px; }
.download-link[aria-disabled="true"] { background: #eef1f4; border-color: #e1e5eb; color: #96a0ab; pointer-events: none; }
.store-option { font-size: 12px; line-height: 1.9; margin-top: 22px; }
.store-option a, .privacy-link { color: var(--accent); text-decoration: underline; text-underline-offset: 4px; }
.store-option .icon { width: 13px; height: 13px; }
.guide-section { margin-bottom: 56px; padding: 22px 26px; border: 1px solid var(--line); border-radius: 16px; background: #fff; }
.guide-section summary { font-size: 14px; }
.setup-steps { margin: 28px 0 4px; padding-left: 22px; color: var(--accent); }
.setup-steps li { padding-left: 8px; margin-bottom: 20px; }
.setup-steps li:last-child { margin-bottom: 0; }
.setup-steps h3 { font-size: 14px; color: var(--ink); margin-bottom: 6px; }
.setup-steps p { font-size: 13px; }
.faq { display: grid; grid-template-columns: .8fr 1.2fr; gap: 64px; padding-block: 8px 72px; }
.faq details { padding: 19px 0; border-bottom: 1px solid var(--line); }
.faq details:first-child { padding-top: 4px; }
summary { cursor: pointer; font-size: 14px; font-weight: 500; list-style: none; padding-right: 25px; position: relative; }
summary::-webkit-details-marker { display: none; }
summary:after { content: "+"; position: absolute; right: 2px; top: 0; font-size: 18px; font-weight: 400; color: #9ca5b0; line-height: 1.4; }
details[open] > summary:after { content: "−"; }
.faq details p { font-size: 13px; line-height: 1.95; margin-top: 14px; overflow-wrap: anywhere; }
.privacy-link { display: inline-block; margin-top: 22px; font-size: 12px; }
.skip { position: absolute; left: 16px; top: -80px; padding: 10px; background: #fff; z-index: 10; }
.skip:focus { top: 10px; }
.sr-only { position: absolute; width: 1px; height: 1px; overflow: hidden; clip-path: inset(50%); white-space: nowrap; }
@media (max-width: 1100px) {
  .wrap { width: calc(100% - 56px); }
  .tool-card { padding: 24px; }
  .card-heading { gap: 12px; }
  .card-heading h2 { font-size: 26px; }
  .card-heading img { width: 54px; height: 54px; }
  .card-preview { height: 200px; }
  .product-heading { gap: 32px; }
  .demo-section, .use-cases, .faq { gap: 36px; }
  .footer-main { gap: 20px; }
  .feedback-label { display: none; }
  .download-card { padding: 20px; }
  .download-os h3 { font-size: 15px; }
}
@media (max-width: 800px) {
  .product-heading { grid-template-columns: 1fr; gap: 32px; }
  .product-heading h1 br { display: none; }
  .product-preview { max-width: 560px; width: 100%; margin: 0 auto; }
  .music-preview { max-width: 680px; width: 100%; margin: 0 auto; }
  .downloads { grid-template-columns: 1fr; gap: 14px; }
  .download-card { display: grid; grid-template-columns: 1fr 180px; gap: 12px 20px; align-items: center; }
  .download-os { grid-row: 1; }
  .release-meta { margin: 0; grid-column: 1; grid-row: 2; }
  .download-card .button { grid-column: 2; grid-row: 1 / 3; }
  .download-card small { grid-column: 1 / -1; margin: 0; }
  .download-os h3 { font-size: 18px; }
  .demo-section, .use-cases, .faq { grid-template-columns: 1fr; gap: 28px; }
  .scenario-list { margin-top: 24px; gap: 14px; }
  .scenario-list > div { grid-template-columns: 44px 1fr; }
  .footer-links { margin-left: 0; }
  .contact-block { margin-left: auto; }
}
@media (max-width: 720px) {
  .wrap { width: calc(100% - 36px); }
  .header { height: 80px; gap: 12px; }
  .brand { gap: 9px; font-size: 18px; }
  .brand-icon { width: 40px; height: 40px; }
  .header nav a { font-size: 13px; padding-inline: 10px; }
  .catalog { padding-block: 32px 40px; }
  .catalog-heading { align-items: stretch; flex-direction: column; gap: 22px; margin-bottom: 24px; }
  .catalog-title h1 { font-size: 27px; }
  .catalog-title p { font-size: 13px; }
  .search { width: 100%; height: 46px; }
  .tool-grid { grid-template-columns: 1fr; gap: 22px; }
  .tool-card { padding: 24px; }
  .card-summary { min-height: 0; font-size: 14px; margin-top: 20px; }
  .card-preview { height: 200px; margin-block: 22px; }
  .writing-preview img { width: 236px; }
  .card-heading img { width: 54px; height: 54px; }
  .card-heading h2 { font-size: 26px; }
  .category-label { font-size: 10px; padding: 3px 7px; }
  .platforms { gap: 10px; }
  .card-footer strong { font-size: 12px; gap: 5px; }
  .card-footer { gap: 8px; }
  .footer-main { padding-block: 24px 34px; gap: 16px; }
  .copyright { flex: 1; }
  .contact-block { width: 100%; margin-left: 0; gap: 12px; }
  .feedback-label { display: inline; }
  .copy-email { margin-left: auto; }
  .copy-email > span { display: none; }
  .copy-email .icon { width: 18px; height: 18px; }
  .copy-status { left: 0; right: auto; }
  .back-link { margin-bottom: 28px; }
  .product-hero { padding-block: 24px 40px; }
  .product-heading h1 { font-size: 32px; }
  .product-name { margin-bottom: 22px; }
  .product-name img { width: 58px; height: 58px; }
  .lead { font-size: 14px; margin: 15px 0 23px; }
  .product-preview { padding: 24px; }
  .music-preview { padding: 12px 12px 14px; }
  .music-preview img { border-radius: 10px; }
  h2 { font-size: 24px; }
  .demo-section, .use-cases { padding-block: 34px 40px; }
  .tool-demo { padding: 20px; }
  .demo-tabs { gap: 2px; }
  .demo-tabs button { font-size: 11px; padding: 8px 3px; }
  .result-paper { padding: 18px; }
  .cases-list article { gap: 14px; grid-template-columns: 80px 1fr; }
  .cases-list p { font-size: 13px; }
  .download { padding-block: 34px 40px; }
  .download > .section-heading { flex-direction: column; align-items: flex-start; gap: 12px; }
  .section-heading p { font-size: 13px; }
  .download-card { grid-template-columns: 1fr; padding: 22px; gap: 14px; }
  .release-meta { grid-column: auto; grid-row: auto; }
  .download-card .button { grid-column: auto; grid-row: auto; }
  .download-card small { grid-column: auto; min-height: 0; }
  .guide-section { padding: 20px; margin-bottom: 36px; }
  .faq { padding-bottom: 48px; gap: 24px; }
  .search-empty { padding: 48px 20px; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *:before, *:after { transition: none !important; animation: none !important; }
  .tool-card:hover, .tool-card:hover .icon { transform: none; }
}