:root {
  --paper: #f5f2e9;
  --paper-strong: #fff;
  --ink: #2c3e2b;
  --ink-soft: #566252;
  --line: rgba(44, 62, 43, .17);
  --accent: #c84b31;
  --accent-dark: #963722;
  --sky: #a8d1e7;
  --shadow: 0 16px 36px rgba(44, 62, 43, .12);
  --radius: 10px;
  --max: 1180px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family: "Noto Sans SC", "Microsoft YaHei", system-ui, sans-serif;
  line-height: 1.75;
  text-rendering: optimizeLegibility;
}
a { color: inherit; }
img { display: block; max-width: 100%; }
.icon-sprite { position: absolute; width: 0; height: 0; overflow: hidden; }
.icon { width: 1.05em; height: 1.05em; flex: none; fill: none; stroke: currentColor; stroke-width: 1.9; stroke-linecap: round; stroke-linejoin: round; }
.skip-link { position: absolute; left: 1rem; top: -4rem; z-index: 20; padding: .65rem 1rem; background: var(--accent); color: #fff; }
.skip-link:focus { top: 1rem; }
.site-header { position: sticky; top: 0; z-index: 10; background: rgba(44, 62, 43, .96); color: #fff; border-bottom: 1px solid rgba(255,255,255,.16); backdrop-filter: blur(12px); }
.nav-wrap { width: min(var(--max), calc(100% - 2rem)); min-height: 68px; margin: auto; display: flex; align-items: center; justify-content: space-between; gap: 1.25rem; }
.brand { display: inline-flex; align-items: center; gap: .75rem; text-decoration: none; font-weight: 800; letter-spacing: .02em; white-space: nowrap; }
.brand-mark { width: 38px; height: 38px; border-radius: 50%; object-fit: cover; border: 2px solid rgba(255,255,255,.75); }
.brand-text small { display: block; color: var(--sky); font-size: .7rem; letter-spacing: .12em; line-height: 1.1; }
.brand-text span { font-family: Georgia, serif; font-size: .98rem; line-height: 1.2; }
.nav-toggle { display: none; align-items: center; gap: .42rem; border: 1px solid rgba(255,255,255,.35); background: transparent; color: #fff; border-radius: 7px; padding: .45rem .65rem; font: inherit; cursor: pointer; }
.primary-nav { display: flex; align-items: center; gap: .15rem; }
.primary-nav a { position: relative; display: inline-flex; align-items: center; gap: .34rem; padding: .5rem .58rem; color: rgba(255,255,255,.86); text-decoration: none; font-size: .88rem; border-radius: 6px; }
.primary-nav .icon { color: var(--sky); font-size: .96rem; }
.primary-nav a:hover, .primary-nav a:focus-visible { color: #fff; background: rgba(255,255,255,.12); outline: none; }
.primary-nav a::after { content: ""; position: absolute; left: .58rem; right: .58rem; bottom: .18rem; height: 2px; border-radius: 999px; background: var(--sky); transform: scaleX(0); transform-origin: left center; transition: transform .3s ease; }
.primary-nav a:hover::after, .primary-nav a:focus-visible::after { transform: scaleX(1); }
.cta, .cta:visited { display: inline-flex; align-items: center; justify-content: center; gap: .5rem; border-radius: 7px; background: var(--accent); color: #fff; text-decoration: none; padding: .75rem 1.1rem; font-weight: 800; border: 1px solid var(--accent); box-shadow: 0 8px 18px rgba(200,75,49,.22); transition: transform .3s ease, background .3s ease, box-shadow .3s ease, filter .3s ease; }
.cta:hover, .cta:focus-visible { background: var(--accent-dark); transform: translateY(-2px) scale(1.04); box-shadow: 0 12px 26px rgba(200,75,49,.34); filter: brightness(1.08); outline: none; }
.cta-secondary { background: transparent; border-color: var(--ink); color: var(--ink); box-shadow: none; }
.cta-secondary:hover, .cta-secondary:focus-visible { background: var(--ink); color: #fff; box-shadow: 0 10px 22px rgba(44,62,43,.24); }
.hero { position: relative; min-height: min(730px, 82vh); display: grid; align-items: end; overflow: hidden; background: var(--ink); }
.hero-media { position: absolute; inset: 0; display: block; width: 100vw; max-width: none; height: 100%; min-height: 100%; object-fit: cover; object-position: center; opacity: .86; transition: transform .3s ease, filter .3s ease; }
.hero:hover .hero-media { transform: scale(1.03); filter: brightness(1.06); }
.hero::after { content: ""; position: absolute; inset: 0; background: linear-gradient(90deg, rgba(22,38,25,.88) 0%, rgba(22,38,25,.54) 43%, rgba(22,38,25,.14) 100%), linear-gradient(0deg, rgba(22,38,25,.7), transparent 55%); }
.hero-inner { position: relative; z-index: 1; width: min(var(--max), calc(100% - 2rem)); margin: 0 auto; padding: 7rem 0 5.5rem; }
.eyebrow { margin: 0 0 .8rem; color: var(--sky); text-transform: uppercase; letter-spacing: .18em; font-size: .77rem; font-weight: 800; }
h1, h2, h3 { margin: 0; font-family: Georgia, "Noto Serif SC", serif; line-height: 1.18; letter-spacing: .01em; }
h1 { max-width: 720px; color: #fff; font-size: clamp(2rem, 4vw, 3.65rem); }
.hero-subtitle { max-width: 660px; margin: 1.25rem 0 1.75rem; color: rgba(255,255,255,.9); font-size: clamp(1rem, 2vw, 1.22rem); }
.hero-actions { display: flex; flex-wrap: wrap; gap: .8rem; }
.hero-meta { display: flex; flex-wrap: wrap; gap: .5rem .9rem; margin-top: 2rem; color: rgba(255,255,255,.82); font-size: .88rem; }
.hero-meta span { display: inline-flex; align-items: center; gap: .45rem; }
.hero-meta span::before { content: ""; width: 6px; height: 6px; border-radius: 50%; background: var(--accent); }
.section { padding: 5.5rem 0; }
.section-alt { background: #ebe9df; }
.container { width: min(var(--max), calc(100% - 2rem)); margin: 0 auto; }
.section-heading { display: flex; align-items: end; justify-content: space-between; gap: 2rem; margin-bottom: 2rem; }
.section-kicker { margin: 0 0 .45rem; color: var(--accent); font-weight: 900; font-size: .78rem; letter-spacing: .13em; text-transform: uppercase; }
h2 { font-size: clamp(1.5rem, 2.35vw, 2.2rem); }
.section-lead { max-width: 610px; margin: .9rem 0 0; color: var(--ink-soft); }
.intro-grid { display: grid; grid-template-columns: 1.15fr .85fr; gap: 2.2rem; align-items: center; }
.intro-copy p { margin: 0 0 1rem; }
.intro-image { position: relative; border-radius: var(--radius); overflow: hidden; box-shadow: var(--shadow); background: var(--paper-strong); }
.intro-image::after, .screenshot-main::after, .screenshot-thumb::after { content: ""; position: absolute; inset: 0; z-index: 1; pointer-events: none; background: linear-gradient(135deg, rgba(200,75,49,.28), rgba(44,62,43,.5)); opacity: 0; transition: opacity .3s ease; }
.intro-image:hover::after, .screenshot-main:hover::after, .screenshot-thumb:hover::after, .screenshot-thumb:focus-visible::after { opacity: 1; }
.intro-image img { width: 100%; height: auto; aspect-ratio: auto; object-fit: contain; transition: transform .3s ease, filter .3s ease; }
.screenshot-main img, .screenshot-thumb img { transition: transform .3s ease, filter .3s ease; }
.intro-image:hover img, .screenshot-main:hover img { transform: scale(1.05); filter: brightness(1.08); }
.screenshot-thumb:hover img, .screenshot-thumb:focus-visible img { transform: none; filter: brightness(1.08); }
.caption { position: relative; z-index: 2; padding: .7rem .9rem; color: var(--ink-soft); font-size: .8rem; background: var(--paper-strong); }
.feature-grid, .guide-grid, .content-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 1rem; }
.card { background: var(--paper-strong); border: 1px solid var(--line); border-radius: var(--radius); padding: 1.25rem; box-shadow: 0 8px 22px rgba(44,62,43,.06); transition: transform .3s ease, box-shadow .3s ease, border-color .3s ease; }
.card:hover, .card:focus-within { transform: translateY(-7px); border-color: rgba(200,75,49,.42); box-shadow: 0 16px 34px rgba(44,62,43,.15), 0 0 22px rgba(200,75,49,.2); }
.card h3 { font-size: 1.15rem; margin-bottom: .45rem; }
.card p { margin: 0; color: var(--ink-soft); }
.numbered { display: grid; grid-template-columns: auto 1fr; gap: .9rem; }
.number { width: 2rem; height: 2rem; display: grid; place-items: center; flex: none; border-radius: 50%; background: var(--ink); color: #fff; font-weight: 800; font-size: .85rem; }
.screenshot-viewer { display: grid; grid-template-columns: minmax(0, 1.7fr) minmax(280px, .7fr); gap: 1rem; align-items: stretch; }
.screenshot-main { position: relative; margin: 0; min-height: 480px; overflow: hidden; border-radius: var(--radius); background: var(--ink); box-shadow: var(--shadow); }
.screenshot-main img { width: 100%; height: 100%; min-height: 480px; aspect-ratio: 16 / 9; object-fit: cover; }
.screenshot-thumbs { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); grid-template-rows: repeat(3, minmax(0, 1fr)); gap: .75rem; }
.screenshot-thumb { position: relative; min-width: 0; min-height: 0; padding: 0; overflow: hidden; border: 3px solid transparent; border-radius: 8px; background: var(--ink); cursor: pointer; opacity: .7; transition: opacity .3s ease, border-color .3s ease, transform .3s ease, filter .3s ease; }
.screenshot-thumb img { width: 100%; height: 100%; object-fit: contain; object-position: center; background: var(--ink); }
.thumb-icon { position: absolute; right: .45rem; bottom: .45rem; display: grid; place-items: center; width: 1.85rem; height: 1.85rem; border: 1px solid rgba(255,255,255,.45); border-radius: 50%; background: rgba(22,38,25,.76); color: #fff; opacity: 0; transform: scale(.85); transition: opacity .2s ease, transform .2s ease; }
.screenshot-thumb:hover .thumb-icon, .screenshot-thumb:focus-visible .thumb-icon, .screenshot-thumb.is-active .thumb-icon { opacity: 1; transform: scale(1); }
.screenshot-thumb:hover, .screenshot-thumb:focus-visible { opacity: 1; transform: translateY(-2px) scale(1.03); filter: brightness(1.08); outline: none; }
.screenshot-thumb.is-active { border-color: var(--accent); opacity: 1; }
.timeline { border-left: 2px solid var(--accent); margin-left: .5rem; padding-left: 1.35rem; display: grid; gap: 1.2rem; }
.timeline-item { position: relative; padding: 1.1rem 1.25rem; background: var(--paper-strong); border: 1px solid var(--line); border-radius: var(--radius); transition: transform .3s ease, box-shadow .3s ease, border-color .3s ease; }
.timeline-item.reveal { transition: opacity .55s ease, transform .3s ease, box-shadow .3s ease, border-color .3s ease; }
.timeline-item.reveal.is-visible:hover, .timeline-item.reveal.is-visible:focus-within { transform: translateY(-4px); border-color: rgba(200,75,49,.48); box-shadow: 0 14px 30px rgba(44,62,43,.14), 0 0 18px rgba(200,75,49,.12); }
.timeline-item::before { content: ""; position: absolute; left: -1.72rem; top: 1.35rem; width: .7rem; height: .7rem; background: var(--accent); border: 3px solid var(--paper); border-radius: 50%; }
.timeline-date { margin: 0 0 .35rem; color: var(--accent-dark); font-weight: 900; font-size: .87rem; }
.timeline-item h3 { font-size: 1.1rem; margin-bottom: .4rem; }
.timeline-item p { margin: 0; color: var(--ink-soft); }
.update-list { margin: .75rem 0 0; padding-left: 1.25rem; color: var(--ink-soft); }
.update-list li + li { margin-top: .35rem; }
.faq-list { display: grid; gap: .7rem; }
details { background: var(--paper-strong); border: 1px solid var(--line); border-radius: 8px; padding: 0 1.1rem; transition: transform .25s ease, box-shadow .25s ease, border-color .25s ease, background-color .25s ease; }
details:hover, details:focus-within { transform: translateY(-2px); border-color: rgba(200,75,49,.46); box-shadow: 0 10px 24px rgba(44,62,43,.12), 0 0 16px rgba(200,75,49,.1); background: #fffdf8; }
summary { cursor: pointer; list-style: none; padding: 1rem 2rem 1rem 0; position: relative; font-weight: 800; transition: color .2s ease; }
summary:hover, summary:focus-visible { color: var(--accent-dark); outline: none; }
summary::-webkit-details-marker { display: none; }
summary::after { content: "+"; position: absolute; right: .2rem; top: .85rem; color: var(--accent); font-size: 1.5rem; font-weight: 400; }
details[open] summary::after { content: "−"; }
details p { margin: 0 0 1rem; color: var(--ink-soft); }
.friend-links { padding: 2.3rem 0 2.5rem; background: var(--ink); color: #fff; border-bottom: 1px solid rgba(255,255,255,.14); }
.friend-links-inner { text-align: center; }
.friend-links h2 { margin-bottom: 1.15rem; color: #fff; font-family: "Noto Sans SC", "Microsoft YaHei", system-ui, sans-serif; font-size: 1.35rem; }
.friend-link-list { display: flex; flex-wrap: wrap; justify-content: center; gap: .7rem; }
.friend-link-list a { display: inline-flex; align-items: center; justify-content: center; min-height: 42px; padding: .62rem 1.15rem; border: 1px solid rgba(255,255,255,.28); border-radius: 999px; background: var(--paper-strong); color: var(--ink); text-decoration: none; font-weight: 800; line-height: 1.2; box-shadow: 0 7px 18px rgba(0,0,0,.14); transition: transform .25s ease, background-color .25s ease, color .25s ease, border-color .25s ease, box-shadow .25s ease; }
.friend-link-list a:hover, .friend-link-list a:focus-visible { transform: translateY(-3px); border-color: var(--sky); background: var(--sky); color: var(--ink); box-shadow: 0 12px 24px rgba(0,0,0,.22); outline: none; }
.site-footer { padding: 2rem 0; background: var(--ink); color: rgba(255,255,255,.78); }
.footer-inner { display: flex; justify-content: space-between; gap: 1rem; align-items: center; }
.footer-inner p { margin: 0; font-size: .86rem; }
.footer-links { display: flex; gap: 1rem; font-size: .86rem; }
.footer-links a { display: inline-flex; align-items: center; gap: .35rem; color: #fff; text-underline-offset: .25em; }
.floating-cta { position: fixed; right: clamp(1rem, 3vw, 2.25rem); bottom: calc(1rem + env(safe-area-inset-bottom)); z-index: 9; padding: .78rem 1.05rem; border-radius: 999px; box-shadow: 0 12px 28px rgba(44,62,43,.24), 0 0 0 3px rgba(245,242,233,.76); }
.floating-cta .icon { width: 1.05rem; height: 1.05rem; }
.floating-cta:hover, .floating-cta:focus-visible { transform: translateY(-4px) scale(1.04); }
.reveal { opacity: 0; transform: translateY(16px); transition: opacity .55s ease, transform .55s ease; }
.card.reveal { transition: opacity .55s ease, transform .3s ease, box-shadow .3s ease, border-color .3s ease; }
.reveal.is-visible { opacity: 1; transform: none; }
@media (max-width: 900px) {
  .nav-toggle { display: inline-flex; }
  .primary-nav { position: absolute; left: 1rem; right: 1rem; top: calc(100% + .45rem); display: none; flex-direction: column; align-items: stretch; padding: .55rem; border-radius: 8px; background: var(--ink); box-shadow: var(--shadow); }
  .primary-nav.is-open { display: flex; }
  .primary-nav a { padding: .7rem .8rem; }
  .nav-wrap > .cta { display: none; }
  .intro-grid, .screenshot-viewer { grid-template-columns: 1fr; }
  .screenshot-main, .screenshot-main img { min-height: 0; }
  .screenshot-thumbs { grid-template-columns: repeat(3, minmax(0, 1fr)); grid-template-rows: repeat(2, 110px); }
}
@media (max-width: 640px) {
  .nav-wrap, .container, .hero-inner { width: min(100% - 1.25rem, var(--max)); }
  .brand-text span { font-size: .84rem; }
  .hero { min-height: 680px; }
  .hero-inner { padding: 6rem 0 3.5rem; }
  h1 { font-size: clamp(1.85rem, 8.5vw, 2.75rem); }
  .section { padding: 3.5rem 0; }
  .section-heading { display: block; }
  .feature-grid, .guide-grid, .content-grid { grid-template-columns: 1fr; }
  .screenshot-thumbs { gap: .5rem; grid-template-rows: repeat(2, 82px); }
  .footer-inner { display: block; }
  .footer-links { margin-top: .7rem; }
  .friend-links { padding: 2rem 0; }
  .friend-link-list { gap: .55rem; }
  .friend-link-list a { flex: 1 1 calc(50% - .55rem); min-width: 0; padding: .65rem .75rem; }
  .floating-cta { right: .85rem; bottom: calc(.85rem + env(safe-area-inset-bottom)); padding: .7rem .9rem; }
}
@media (prefers-reduced-motion: reduce) { *, *::before, *::after { scroll-behavior: auto !important; transition-duration: .01ms !important; animation-duration: .01ms !important; } .reveal { opacity: 1; transform: none; } }