:root {
  color-scheme: light;
  --bg: #ffffff;
  --soft: #f5f6f7;
  --line: #dee0e3;
  --text: #1f2329;
  --muted: #646a73;
  --blue: #3370ff;
  --blue-soft: #e8f0ff;
  font-family: Inter, "PingFang SC", "Microsoft YaHei", system-ui, -apple-system, sans-serif;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; min-width: 320px; color: var(--text); background: var(--bg); }
a { color: inherit; text-decoration: none; }
button, a { -webkit-tap-highlight-color: transparent; }

.site-header,
main,
footer { width: min(2200px, calc(100% - 64px)); margin-inline: auto; }

.site-header {
  height: 72px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-bottom: 1px solid var(--line);
}
.brand { display: inline-flex; align-items: center; gap: 12px; font-size: 16px; font-weight: 700; }
.brand-mark { width: 34px; height: 34px; display: grid; place-items: center; border-radius: 9px; background: var(--blue); }
.brand-mark svg { width: 21px; fill: #fff; }
.brand-mark .brand-cut { fill: #fff; }
.header-download { padding: 10px 18px; border: 1px solid #c9d8ff; border-radius: 8px; color: #245bdb; background: #f2f6ff; font-size: 14px; font-weight: 600; transition: .18s ease; }
.header-download:hover { color: #fff; border-color: var(--blue); background: var(--blue); }

.hero { min-height: 164px; padding: 28px 0 26px; border-bottom: 1px solid var(--line); display: flex; align-items: end; justify-content: space-between; gap: 60px; }
.hero-copy { max-width: 900px; }
.eyebrow, .section-heading > span, .section-kicker { color: #8a8a8a; font-size: 11px; font-weight: 700; letter-spacing: .14em; }
h1 { margin: 10px 0 8px; font-size: clamp(36px, 3vw, 48px); line-height: 1.12; letter-spacing: -.04em; }
.hero-lead { max-width: 760px; margin: 0; color: var(--muted); font-size: 17px; line-height: 1.75; }
.primary-button { flex: 0 0 auto; display: inline-flex; align-items: center; gap: 38px; padding: 14px 20px; color: #fff; background: var(--blue); border-radius: 8px; font-size: 15px; font-weight: 700; transition: .18s ease; }
.primary-button:hover { background: #285ee9; transform: translateY(-1px); }

.catalog { padding: 28px 0 66px; }
.section-heading { display: flex; align-items: end; justify-content: space-between; gap: 30px; margin-bottom: 16px; }
.section-heading > div { display: grid; gap: 5px; }
.section-heading h2, .verify h2 { margin: 0; font-size: clamp(28px, 2.4vw, 36px); letter-spacing: -.035em; }
.section-heading p { margin: 0 0 3px; color: var(--muted); font-size: 15px; }
.resource-layout { min-height: 720px; display: grid; grid-template-columns: 440px 1fr; align-items: start; border: 1px solid var(--line); border-radius: 14px; overflow: visible; box-shadow: 0 8px 32px rgba(31,35,41,.05); }
.software-list { position: sticky; top: 16px; z-index: 2; max-height: calc(100vh - 32px); padding: 16px; overflow-y: auto; overscroll-behavior: contain; scrollbar-width: thin; background: #f7f8fa; border-right: 1px solid var(--line); border-radius: 13px 0 0 13px; }
.software-item { width: 100%; min-height: 96px; padding: 16px; border: 1px solid transparent; border-radius: 10px; background: transparent; display: grid; grid-template-columns: 48px 1fr 20px; align-items: center; gap: 15px; color: var(--text); text-align: left; cursor: pointer; transition: .15s ease; }
.software-item + .software-item { margin-top: 8px; }
.software-item:hover { background: #eef0f3; }
.software-item.active { color: #1456f0; border-color: #c9d8ff; background: var(--blue-soft); box-shadow: none; }
.software-icon { width: 46px; height: 46px; display: grid; place-items: center; border-radius: 10px; background: #e8eaed; color: #4e5969; font-size: 17px; font-weight: 800; }
.software-item.active .software-icon { background: var(--blue); color: #fff; }
.software-item > span:nth-child(2) { min-width: 0; display: flex; flex-direction: column; gap: 6px; }
.software-item strong { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; font-size: 18px; line-height: 1.35; }
.software-item small { color: #8f959e; font-size: 13px; }
.item-arrow { color: #8f959e; font-size: 24px; }
.tutorial-area { background: #fff; }
.tutorial-panel { min-height: 718px; padding: 38px 58px 32px; display: flex; flex-direction: column; animation: panel-in .18s ease; }
.tutorial-panel[hidden] { display: none; }
@keyframes panel-in { from { opacity: 0; transform: translateY(4px); } to { opacity: 1; transform: none; } }
.detail-status { display: inline-flex; align-items: center; align-self: flex-start; gap: 8px; padding: 5px 10px; border-radius: 6px; color: #245bdb; background: #f0f4ff; font-size: 12px; font-weight: 600; }
.detail-status span { width: 6px; height: 6px; border-radius: 50%; background: var(--blue); }
.tutorial-panel h3 { margin: 16px 0 7px; font-size: clamp(30px, 2.5vw, 40px); letter-spacing: -.04em; }
.detail-lead { margin: 0; color: var(--muted); font-size: 16px; line-height: 1.7; }
.download-banner { margin-top: 24px; padding: 18px 20px; display: grid; grid-template-columns: 48px 1fr auto; align-items: center; gap: 16px; border: 1px solid #c9d8ff; border-radius: 12px; background: #f5f8ff; }
.download-banner-icon { width: 48px; height: 48px; display: grid; place-items: center; border-radius: 10px; color: #fff; background: var(--blue); font-size: 18px; font-weight: 800; }
.download-banner-copy { min-width: 0; display: flex; flex-direction: column; gap: 5px; }
.download-banner-copy strong { color: #1f2329; font-size: 18px; }
.download-banner-copy small { color: #646a73; font-size: 13px; }
.download-banner a { padding: 12px 20px; border-radius: 8px; color: #fff; background: var(--blue); font-size: 14px; font-weight: 700; }
.download-banner a:hover { background: #285ee9; }
.remote-download-address { margin-top: 24px; padding: 19px 22px; display: flex; align-items: center; gap: 22px; border: 1px solid #c9d8ff; border-radius: 12px; background: #f5f8ff; }
.remote-download-address span { flex: 0 0 auto; color: #4e5969; font-size: 14px; font-weight: 600; }
.remote-download-address a { min-width: 0; color: var(--blue); font-size: 18px; font-weight: 700; overflow-wrap: anywhere; }
.remote-download-address a:hover { text-decoration: underline; }
.install-guide { margin-top: 28px; padding-top: 2px; }
.install-step-list { margin: 0; padding: 0; list-style: none; }
.install-step { position: relative; padding: 16px 0 30px; display: grid; grid-template-columns: 42px minmax(0, 1fr); gap: 18px; }
.install-step:not(:last-child)::before { content: ""; position: absolute; left: 17px; top: 54px; bottom: -2px; width: 2px; background: #dbe5ff; }
.install-step-content { min-width: 0; padding: 0 0 2px; }
.install-step-content h4 { margin: 3px 0 6px; color: #1f2329; font-size: 19px; line-height: 1.45; }
.install-step-content p { margin: 0 0 16px; color: #646a73; font-size: 14px; line-height: 1.75; }
.install-step-content img { width: auto; max-width: 100%; height: auto; display: block; border: 1px solid #dee0e3; border-radius: 10px; background: #fff; box-shadow: 0 4px 18px rgba(31,35,41,.06); cursor: zoom-in; }
.install-step-note .install-step-content { padding: 18px 22px; border-radius: 10px; background: #f5f8ff; }
.install-step-note .install-step-content h4 { margin-top: 0; }
.install-step-note .install-step-content p { margin-bottom: 0; }
.tutorial-block { margin-top: 22px; padding: 22px 26px 18px; border: 1px solid #e8eaed; border-radius: 12px; background: #fff; }
.tutorial-heading { margin-bottom: 12px; display: flex; align-items: center; justify-content: space-between; }
.tutorial-heading span { font-size: 19px; font-weight: 700; }
.tutorial-heading strong { padding: 5px 9px; border-radius: 6px; color: #245bdb; background: #f0f4ff; font-size: 12px; }
.step-list { margin: 0; padding: 0; list-style: none; display: grid; }
.step-list li { min-width: 0; position: relative; padding: 13px 2px; display: grid; grid-template-columns: 38px 1fr; align-items: start; gap: 15px; border-bottom: 1px solid #eef0f2; }
.step-list li:last-child { border-bottom: 0; }
.step-number { width: 34px; height: 34px; display: grid; place-items: center; border-radius: 9px; color: #fff; background: var(--blue); font-size: 15px; font-weight: 700; box-shadow: 0 0 0 4px #e8f0ff; }
.step-copy { display: flex; flex-direction: column; gap: 4px; }
.step-copy strong { color: #1f2329; font-size: 16px; line-height: 1.4; }
.step-copy small { color: #646a73; font-size: 13px; line-height: 1.55; }
.step-copy b { color: #1456f0; }
.detail-footer { margin-top: auto; padding-top: 20px; display: flex; align-items: center; justify-content: space-between; border-top: 1px solid var(--line); }
.detail-footer > span { color: #8f959e; font-size: 13px; }
.detail-footer a { padding: 13px 22px; border-radius: 8px; background: var(--blue); color: #fff; font-size: 14px; font-weight: 700; }
.detail-footer a:hover { background: #285ee9; }

.verify { padding: 76px 0 90px; display: grid; grid-template-columns: .8fr 1.2fr; gap: 60px; align-items: start; border-top: 1px solid var(--line); }
.verify h2 { margin-top: 15px; }
.verify-copy p { margin: 18px 0 0; color: var(--muted); font-size: 14px; line-height: 1.8; }
.checksum-list { display: grid; gap: 12px; }
.checksum-card { padding: 22px; border: 1px solid var(--line); border-radius: 10px; background: var(--soft); }
.checksum-head { display: flex; align-items: center; justify-content: space-between; gap: 20px; margin-bottom: 14px; color: #555; font-size: 12px; }
.checksum-head button { border: 0; background: transparent; color: #111; cursor: pointer; font-weight: 700; font-size: 12px; padding: 4px; }
.checksum-card code { display: block; color: #333; overflow-wrap: anywhere; font-size: 12px; line-height: 1.75; }
.checksum-meta { margin-top: 14px; padding-top: 13px; border-top: 1px solid #dfdfdf; display: flex; justify-content: space-between; gap: 20px; color: #8b8b8b; font-size: 11px; }

footer { min-height: 80px; border-top: 1px solid var(--line); display: flex; align-items: center; justify-content: space-between; color: #8a8a8a; font-size: 11px; }
.toast { position: fixed; left: 50%; bottom: 25px; transform: translate(-50%, 20px); padding: 11px 16px; border-radius: 7px; background: #171717; color: #fff; font-size: 12px; font-weight: 700; opacity: 0; pointer-events: none; transition: .2s ease; }
.toast.show { opacity: 1; transform: translate(-50%, 0); }
.back-to-top { position: fixed; right: 26px; bottom: 30px; z-index: 50; width: 76px; height: 82px; padding: 10px 8px; display: flex; align-items: center; justify-content: center; flex-direction: column; gap: 4px; border: 1px solid #d8dbe0; border-radius: 18px; color: #1f2329; background: rgba(255,255,255,.96); box-shadow: 0 8px 28px rgba(31,35,41,.12); cursor: pointer; opacity: 0; pointer-events: none; transform: translateY(14px); transition: opacity .2s ease, transform .2s ease, border-color .2s ease, box-shadow .2s ease; }
.back-to-top.show { opacity: 1; pointer-events: auto; transform: translateY(0); }
.back-to-top:hover { border-color: #9eb8ff; box-shadow: 0 10px 32px rgba(51,112,255,.18); }
.back-to-top:focus-visible { outline: 3px solid rgba(51,112,255,.25); outline-offset: 3px; }
.back-to-top span { font-size: 34px; font-weight: 300; line-height: .8; }
.back-to-top strong { font-size: 14px; font-weight: 600; white-space: nowrap; }
.image-viewer { position: fixed; inset: 0; z-index: 1000; padding: 36px; display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 12px; background: rgba(15,18,23,.88); backdrop-filter: blur(6px); }
.image-viewer[hidden] { display: none; }
.image-viewer img { width: auto; height: auto; max-width: min(96vw, 3840px); max-height: 88vh; object-fit: contain; border-radius: 8px; background: #fff; box-shadow: 0 18px 60px rgba(0,0,0,.35); }
.image-viewer > span { color: rgba(255,255,255,.78); font-size: 13px; }
.image-viewer-close { position: absolute; top: 18px; right: 22px; width: 44px; height: 44px; border: 1px solid rgba(255,255,255,.32); border-radius: 50%; color: #fff; background: rgba(0,0,0,.25); font-size: 28px; line-height: 1; cursor: pointer; }
.image-viewer-close:hover { background: rgba(255,255,255,.16); }
body.viewer-open { overflow: hidden; }

@media (max-width: 760px) {
  .site-header, main, footer { width: min(100% - 28px, 2200px); }
  .hero { min-height: 260px; padding: 48px 0 42px; align-items: flex-start; flex-direction: column; gap: 28px; }
  .resource-layout, .verify { grid-template-columns: 1fr; }
  .resource-layout { min-height: 0; }
  .software-list { position: static; top: auto; max-height: none; overflow: visible; border-right: 0; border-bottom: 1px solid var(--line); border-radius: 13px 13px 0 0; }
  .tutorial-panel { min-height: 760px; padding: 38px 30px 30px; }
  .download-banner { grid-template-columns: 44px 1fr; }
  .download-banner a { grid-column: 1 / -1; text-align: center; }
  .remote-download-address { align-items: flex-start; flex-direction: column; gap: 8px; }
  .back-to-top { right: 14px; bottom: 18px; width: 62px; height: 68px; border-radius: 15px; }
  .back-to-top span { font-size: 28px; }
  .back-to-top strong { font-size: 12px; }
  .install-step { grid-template-columns: 38px minmax(0, 1fr); gap: 14px; }
  .install-step-content h4 { font-size: 17px; }
  .image-viewer { padding: 14px; }
  .step-list { grid-template-columns: 1fr; }
  .step-list li { display: grid; grid-template-columns: 36px 1fr; gap: 14px; }
  .step-number { margin: 1px 0 0; }
  .verify { gap: 36px; }
  .section-heading { align-items: flex-start; flex-direction: column; gap: 12px; }
}

@media (max-width: 480px) {
  .site-header { height: 68px; }
  .brand { font-size: 14px; }
  .header-download { padding: 8px 11px; }
  h1 { font-size: 46px; }
  .hero-lead { font-size: 15px; }
  .catalog { padding: 60px 0 68px; }
  .download-card { min-height: 230px; }
  .tutorial-panel { min-height: 480px; padding: 32px 20px 24px; }
  .verify { padding: 62px 0 70px; }
  .checksum-card { padding: 18px; }
  .checksum-meta, footer { flex-direction: column; gap: 7px; }
  footer { justify-content: center; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  * { transition-duration: .01ms !important; }
}