* { box-sizing: border-box; margin: 0; padding: 0; }
:root { --brand:#1677ff; --ink:#111827; --text:#4b5563; --muted:#9ca3af; --line:#eef2f6; }
@media (prefers-reduced-motion: no-preference) { html { scroll-behavior: smooth; } }
body { color: var(--text); background:#fff; font-family:"Microsoft YaHei","PingFang SC",system-ui,sans-serif; line-height:1.65; }
a { color: inherit; text-decoration: none; }
img { display: block; max-width: 100%;  height: auto;}
.wrap { width: min(1120px, calc(100% - 40px)); margin: 0 auto; }
.nav { position: sticky; top: 0; z-index: 40; background: rgba(255,255,255,.94); border-bottom: 1px solid var(--line); }
.nav-inner { display: flex; align-items: center; justify-content: space-between; min-height: 64px; }
.brand { display: flex; align-items: center; gap: 10px; color: var(--ink); font-weight: 800; }
.brand-mark { width: 32px; height: 32px; display: grid; place-items: center; border-radius: 8px; color: #fff; background: var(--brand); font-weight: 900; }
.nav-links { display: flex; gap: 26px; font-weight: 600; font-size: 14px; }
.nav-cta, .btn { display: inline-flex; align-items: center; justify-content: center; border-radius: 999px; font-weight: 800; cursor: pointer; border: 0; }
.nav-cta { padding: 9px 18px; color: #fff; background: var(--brand); font-size: 14px; }
.menu-btn { display: none; border: 0; background: none; font-size: 22px; cursor: pointer; }
.mobile-panel { display: none; flex-direction: column; gap: 12px; padding: 0 0 16px; font-weight: 600; }
.mobile-panel.open { display: flex; }
.crumb { padding: 14px 0 0; color: var(--muted); font-size: 13px; }
.hero { position: relative; min-height: 72vh; padding: 72px 0 0; overflow: hidden; color: #fff; text-align: center; background: #0b2a66 url("4.webp") center/cover no-repeat; }
.hero::before { content: ""; position: absolute; inset: 0; background: rgba(8,24,64,.55); }
.hero-inner { position: relative; z-index: 1; display: flex; flex-direction: column; align-items: center; }
.hero h1 { max-width: 880px; font-size: clamp(28px, 5vw, 48px); line-height: 1.22; }
.hero-desc { max-width: 620px; margin-top: 14px; color: rgba(255,255,255,.88); }
.meta { margin-top: 16px; color: rgba(255,255,255,.85); font-size: 14px; font-weight: 700; letter-spacing: .04em; }
.hero-cta { display: flex; flex-wrap: wrap; justify-content: center; gap: 12px; margin-top: 28px; }
.btn { min-width: 148px; height: 50px; padding: 0 22px; font-size: 16px; }
.btn-primary { color: #fff; background: var(--brand); }
.btn-ghost { color: #fff; border: 1px solid rgba(255,255,255,.5); background: rgba(255,255,255,.12); }
.btn-line { color: #fff; border: 1px solid rgba(255,255,255,.7); background: transparent; }
.hero-shot { width: min(1100px,100%); margin-top: 44px; }
.hero-shot img { width: 100%; border-radius: 16px 16px 0 0; }
section { padding: 72px 0; }
.head { max-width: 640px; margin: 0 auto 36px; text-align: center; }
h2 { color: var(--ink); font-size: clamp(24px, 3vw, 36px); }
.head p, .copy p, .prose p { margin-top: 12px; color: var(--muted); }
h3 { color: var(--ink); font-size: 18px; }
.gallery { background: #f8fafc; }
.cards-4 { display: grid; grid-template-columns: repeat(4,1fr); gap: 16px; }
.card { overflow: hidden; border-radius: 16px; background: #fff; border: 1px solid var(--line); }
.card img { width: 100%; height: 150px; object-fit: cover; }
.card-body { padding: 16px; }
.card-body p { margin-top: 6px; font-size: 13px; color: var(--muted); }
.tag { display: inline-block; margin-top: 10px; color: var(--brand); font-size: 12px; font-weight: 800; }
.more { display: block; margin-top: 24px; text-align: center; color: var(--brand); font-weight: 800; }
.zigzag { display: grid; gap: 56px; }
.row { display: grid; grid-template-columns: 1fr 1fr; align-items: center; gap: 40px; }
.row.reverse .media { order: 2; }
.row img { width: 100%; height: 300px; object-fit: cover; border-radius: 16px; }
.text-link { display: inline-block; margin-top: 16px; color: var(--brand); font-weight: 800; }
.download { text-align: center; background: #f8fafc; }
.cards-3 { display: grid; grid-template-columns: repeat(3,1fr); gap: 18px; margin-top: 28px; text-align: center; }
.dl-card { padding: 32px 20px; border-radius: 16px; background: #fff; border: 1px solid var(--line); }
.dl-card .ver { color: var(--ink); font-size: 28px; font-weight: 900; }
.dl-card .size { margin: 8px 0 20px; color: var(--muted); font-size: 14px; }
.dl-card .btn { width: 100%; height: 46px; color: #fff; background: var(--brand); }
.quotes { display: grid; grid-template-columns: repeat(3,1fr); gap: 16px; margin-bottom: 40px; }
.quote { padding: 22px; border-radius: 16px; background: #f8fafc; }
.quote strong { display: block; margin-top: 12px; color: var(--ink); }
.users { display: grid; grid-template-columns: repeat(5,1fr); gap: 12px; margin-bottom: 40px; }
.user { padding: 16px 12px; border: 1px solid var(--line); border-radius: 14px; text-align: center; }
.avatar { width: 40px; height: 40px; margin: 0 auto; display: grid; place-items: center; border-radius: 50%; background: #eef5ff; color: var(--brand); font-weight: 900; }
.user b { display: block; margin: 8px 0 4px; color: var(--ink); font-size: 14px; }
.user p { color: var(--muted); font-size: 13px; }
.stars { margin-top: 6px; color: #f5b301; font-size: 12px; }
.about { display: flex; align-items: center; justify-content: space-between; gap: 28px; padding: 28px; border-radius: 20px; background: #f8fafc; }
.pills { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 12px; }
.pills span { padding: 5px 10px; border-radius: 999px; background: #fff; font-size: 12px; font-weight: 700; color: var(--ink); }
.trust-nums { display: flex; gap: 24px; text-align: center; }
.trust-nums strong { display: block; color: var(--ink); font-size: 26px; }
.prose { max-width: 720px; margin: 0 auto 24px; }
.faq details { padding: 14px 0; border-bottom: 1px solid var(--line); }
.faq summary { cursor: pointer; color: var(--ink); font-weight: 800; }
footer { padding: 36px 0 24px; background: #111827; color: #9ca3af; text-align: center; }
footer .name { color: #fff; font-weight: 800; }
footer p, footer nav { margin-top: 8px; font-size: 13px; }
footer nav { display: flex; justify-content: center; gap: 16px; }
@media (max-width: 980px) {
  .nav-links, .nav-inner > .nav-cta { display: none; }
  .menu-btn { display: block; }
  .cards-4, .cards-3, .quotes { grid-template-columns: 1fr 1fr; }
  .users { grid-template-columns: 1fr 1fr; }
  .row, .row.reverse .media, .about { display: block; }
  .row.reverse .media { order: 0; }
  .row img { height: 200px; margin-bottom: 16px; }
  .about { text-align: center; }
  .trust-nums { justify-content: center; margin-top: 16px; }
}
@media (max-width: 640px) {
  .wrap { width: calc(100% - 28px); }
  .hero { padding-top: 48px; min-height: 0; }
  .cards-4, .cards-3, .quotes, .users { grid-template-columns: 1fr; }
}

.sell { max-width: 720px; margin: 0 auto; display: grid; gap: 16px; }
.sell-item { padding: 20px 22px; border: 1px solid var(--line); border-radius: 16px; background: #fff; }
.sell-item h3 { display: flex; align-items: center; gap: 8px; }
.sell-item h3::before { content: "✓"; color: #0f9d58; }
.sell-item .btn { margin-top: 12px; height: 42px; padding: 0 18px; color: #fff; background: var(--brand); }

/* site-perf */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: .01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .01ms !important;
  }
}
.nav { transform: translateZ(0); }