/* =====================================================================
   雷电模拟器 LDPlayer — global stylesheet
   Native CSS only. No frameworks. Optimised for Core Web Vitals.
   System font stack => zero web-font download, no CLS, fast LCP.
   ===================================================================== */

/* ---------- Design tokens (light only) ---------- */
:root {
  color-scheme: light;
  --bg: #ffffff;
  --bg-soft: #f4f7fc;
  --bg-card: #ffffff;
  --bg-code: #f1f5f9;
  --text: #16203a;
  --text-soft: #4b5870;
  --text-mut: #6b7891;
  --border: #e4e9f2;
  --brand: #2563eb;
  --brand-2: #06b6d4;
  --brand-ink: #1d4ed8;
  --accent: #0ea5e9;
  --warn-bg: #fff7ed;
  --warn-bd: #fed7aa;
  --tip-bg: #ecfdf5;
  --tip-bd: #a7f3d0;
  --note-bg: #eff6ff;
  --note-bd: #bfdbfe;
  --shadow: 0 1px 2px rgba(15,23,42,.06), 0 8px 24px rgba(15,23,42,.06);
  --shadow-sm: 0 1px 2px rgba(15,23,42,.08);
  --radius: 14px;
  --radius-sm: 10px;
  --maxw: 1120px;
  --gradient: linear-gradient(135deg, #2563eb 0%, #0ea5e9 55%, #06b6d4 100%);
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", "Microsoft YaHei",
          "PingFang SC", "Hiragino Sans GB", Roboto, Helvetica, Arial, sans-serif;
  --mono: ui-monospace, SFMono-Regular, Menlo, Consolas, "Liberation Mono", monospace;
}

/* Light theme only — dark theme removed by request. */

/* ---------- Reset / base ---------- */
*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  font-family: var(--font);
  font-size: 17px;
  line-height: 1.75;
  color: var(--text);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}
img { max-width: 100%; height: auto; display: block; }
a { color: var(--brand-ink); text-decoration: none; }
a:hover { text-decoration: underline; }
h1, h2, h3, h4 { line-height: 1.25; color: var(--text); font-weight: 800; }
h1 { font-size: clamp(1.7rem, 4.4vw, 2.7rem); margin: .2em 0 .4em; letter-spacing: -.01em; }
h2 { font-size: clamp(1.35rem, 3vw, 1.85rem); margin: 2em 0 .6em; }
h3 { font-size: clamp(1.1rem, 2.2vw, 1.3rem); margin: 1.5em 0 .4em; }
p { margin: 0 0 1.05em; }
ul, ol { margin: 0 0 1.15em; padding-left: 1.4em; }
li { margin: .35em 0; }
strong { font-weight: 700; }
hr { border: none; border-top: 1px solid var(--border); margin: 2.4em 0; }
code {
  font-family: var(--mono); font-size: .92em;
  background: var(--bg-code); padding: .12em .42em; border-radius: 6px;
  border: 1px solid var(--border);
}

/* ---------- Accessibility ---------- */
.skip-link {
  position: absolute; left: -999px; top: 0; z-index: 999;
  background: var(--brand); color: #fff; padding: .6em 1em; border-radius: 0 0 8px 0;
}
.skip-link:focus { left: 0; }
:focus-visible { outline: 3px solid var(--accent); outline-offset: 2px; border-radius: 4px; }

/* ---------- Layout ---------- */
.container { width: 100%; max-width: var(--maxw); margin-inline: auto; padding-inline: 20px; }
main { display: block; }
.section { padding: 34px 0; }
.lede { font-size: 1.12rem; color: var(--text-soft); }

/* ---------- Header / nav ---------- */
.site-header {
  position: sticky; top: 0; z-index: 50;
  background: color-mix(in srgb, var(--bg) 86%, transparent);
  backdrop-filter: saturate(160%) blur(10px);
  border-bottom: 1px solid var(--border);
}
.nav {
  display: flex; align-items: center; gap: 16px;
  min-height: 62px; max-width: var(--maxw); margin-inline: auto; padding-inline: 20px;
}
.brand { display: inline-flex; align-items: center; gap: 10px; font-weight: 800; color: var(--text); }
.brand:hover { text-decoration: none; }
.brand img { width: 34px; height: 34px; border-radius: 9px; box-shadow: var(--shadow-sm); }
.brand b { font-size: 1.12rem; letter-spacing: -.01em; }
.brand span { color: var(--brand-ink); }
.nav-spacer { flex: 1; }
.nav-links { display: flex; align-items: center; gap: 4px; list-style: none; margin: 0; padding: 0; }
.nav-links a {
  display: inline-block; padding: 8px 12px; border-radius: 9px;
  color: var(--text-soft); font-weight: 600; font-size: .96rem; white-space: nowrap;
}
.nav-links a:hover { background: var(--bg-soft); color: var(--text); text-decoration: none; }
.nav-links a[aria-current="page"] { color: var(--brand-ink); background: var(--bg-soft); }
.icon-btn {
  display: inline-grid; place-items: center; width: 40px; height: 40px;
  border: 1px solid var(--border); border-radius: 10px; background: var(--bg-card);
  color: var(--text); cursor: pointer; font-size: 1.1rem; line-height: 1;
}
.icon-btn:hover { background: var(--bg-soft); }
.nav-toggle { display: none; }

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex; align-items: center; gap: .55em;
  padding: 12px 22px; border-radius: 12px; font-weight: 700; font-size: 1rem;
  border: 1px solid transparent; cursor: pointer; transition: transform .06s ease, box-shadow .2s ease;
}
.btn:hover { text-decoration: none; }
.btn:active { transform: translateY(1px); }
.btn-primary { background: var(--gradient); color: #fff; box-shadow: 0 8px 20px rgba(37,99,235,.32); }
.btn-primary:hover { box-shadow: 0 10px 26px rgba(37,99,235,.42); }
.btn-ghost { background: var(--bg-card); color: var(--text); border-color: var(--border); }
.btn-ghost:hover { background: var(--bg-soft); }
.btn-block { width: 100%; justify-content: center; }
.cta-row { display: flex; flex-wrap: wrap; gap: 12px; margin: 18px 0 6px; }

/* ---------- Cinematic first-screen hero (replica) ---------- */
.fs-hero { position: relative; display: grid; width: 100%; background: #000; overflow: hidden; }
.fs-hero > * { grid-area: 1 / 1; }
.fs-bg, .fs-video { width: 100%; height: 100%; object-fit: cover; }
.fs-overlay { background: rgba(0,0,0,.5); }
@media (min-width: 768px) {
  .fs-hero { aspect-ratio: 16 / 9; max-height: calc(100svh - 62px); }
  .fs-mobile { display: none !important; }
}
@media (max-width: 767.9px) {
  .fs-hero { min-height: 100svh; }
  .fs-video, .fs-overlay, .fs-desktop, .fs-mask { display: none !important; }
  .fs-bg { object-position: top; }
}

/* desktop content */
.fs-desktop {
  position: relative; z-index: 2; padding: 0 24px;
  display: flex; flex-direction: column; align-items: center; justify-content: center; text-align: center;
}
.fs-eyebrow { color: rgba(255,255,255,.82); font-weight: 300; letter-spacing: .14em;
  font-size: clamp(1rem, 1.5vw, 1.4rem); margin: 0 0 .85em; }
.fs-title { color: #fff; font-weight: 800; line-height: 1.18; margin: 0; letter-spacing: -.01em;
  font-size: clamp(1.7rem, 3.1vw, 3.1rem); text-shadow: 0 2px 22px rgba(0,0,0,.5); }
.fs-sub { margin: 14px 0 0; color: rgba(255,255,255,.9); font-size: 14px; line-height: 1.5; text-shadow: 0 1px 8px rgba(0,0,0,.5); }
.screenshot { margin: 1.6em 0; }
.screenshot img { width: 100%; height: auto; border: 1px solid var(--border); border-radius: var(--radius); box-shadow: var(--shadow); }
.screenshot figcaption { margin-top: .6em; font-size: .9rem; color: var(--text-mut); text-align: center; }
.fs-cta { display: flex; flex-direction: column; align-items: center; gap: 16px; margin-top: 30px; }

/* image-based download button */
.fs-btn { position: relative; display: inline-grid; line-height: 0; transition: transform .08s ease; }
.fs-btn:hover { text-decoration: none; transform: translateY(-1px); }
.fs-btn:active { transform: translateY(1px); }
.fs-btn img { grid-area: 1 / 1; height: 80px; width: auto; display: block; }
.fs-btn img.hover { opacity: 0; transition: opacity .3s ease; }
.fs-btn:hover img.hover { opacity: 1; }
.fs-btn .label { grid-area: 1 / 1; place-self: center; pointer-events: none; line-height: 1.15;
  display: flex; flex-direction: column; align-items: center; gap: .1em; padding-bottom: .12em; }
.fs-btn .label b, .fs-btn .label small {
  background: linear-gradient(#5E2F03, #B05C0A); -webkit-background-clip: text; background-clip: text;
  -webkit-text-fill-color: transparent; color: transparent; }
.fs-btn .label b { font-size: 1.3rem; font-weight: 800; }
.fs-btn .label small { font-size: .72rem; font-weight: 600; }
.fs-link { color: #fbbf24; font-weight: 600; font-size: 1rem; }
.fs-link:hover { color: #fde047; text-decoration: none; }

/* bottom fade mask + scroll arrow */
.fs-mask { align-self: end; width: 100%; height: auto; pointer-events: none; }
.fs-arrow { justify-self: center; align-self: end; margin-bottom: 18px; z-index: 3;
  width: 32px; height: 32px; opacity: .85; animation: fs-bounce 1.7s ease-in-out infinite; }
@keyframes fs-bounce { 0%, 100% { transform: translateY(0); } 50% { transform: translateY(9px); } }

/* mobile content */
.fs-mobile { position: relative; z-index: 2; display: flex; flex-direction: column;
  justify-content: space-evenly; gap: 16px; padding: 64px 0 30px; }
.fs-shot { width: 100%; height: auto; }
.fs-mcopy { text-align: center; padding: 0 22px; }
.fs-mtitle { color: #fff; font-weight: 800; font-size: 1.6rem; line-height: 1.3; margin: 0; }
.fs-mcopy p { color: rgba(255,255,255,.86); margin: .5rem 0 1.4rem; font-size: 1.02rem; }
.fs-mobile .fs-btn { margin: 0 auto; }
.fs-mobile .fs-btn img { height: 56px; }
.fs-mobile .fs-btn .label b { font-size: 1rem; }

/* ---------- Breadcrumb ---------- */
.breadcrumb { padding: 14px 0 0; }
.breadcrumb ol { display: flex; flex-wrap: wrap; gap: 8px; list-style: none; margin: 0; padding: 0; font-size: .9rem; color: var(--text-mut); }
.breadcrumb li::after { content: "/"; margin-left: 8px; color: var(--text-mut); }
.breadcrumb li:last-child::after { content: ""; }
.breadcrumb a { color: var(--text-soft); }

/* ---------- Article typography ---------- */
.article { max-width: 760px; }
.article.wide { max-width: var(--maxw); }
.layout { display: grid; grid-template-columns: minmax(0,1fr) 280px; gap: 40px; align-items: start; }
.article h2 { scroll-margin-top: 80px; padding-top: 4px; }
.article h3 { scroll-margin-top: 80px; }
.article ul li::marker { color: var(--brand); }
.article ol { counter-reset: none; }

/* ---------- Sidebar ---------- */
.sidebar { position: sticky; top: 78px; }
.sidebar .widget {
  background: var(--bg-card); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 18px; margin-bottom: 18px; box-shadow: var(--shadow-sm);
}
.sidebar h2, .sidebar h3 { margin: 0 0 12px; font-size: 1.02rem; }
.sidebar ul { list-style: none; margin: 0; padding: 0; }
.sidebar li { margin: 0; }
.sidebar li a { display: block; padding: 7px 0; border-bottom: 1px dashed var(--border); color: var(--text-soft); font-weight: 600; font-size: .94rem; }
.sidebar li:last-child a { border-bottom: none; }
.sidebar li a:hover { color: var(--brand-ink); text-decoration: none; }

/* ---------- Cards / grids ---------- */
.grid { display: grid; gap: 18px; }
.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }
.card {
  background: var(--bg-card); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 20px; box-shadow: var(--shadow-sm);
  transition: transform .12s ease, box-shadow .2s ease, border-color .2s ease;
}
.card:hover { transform: translateY(-2px); box-shadow: var(--shadow); border-color: color-mix(in srgb, var(--brand) 40%, var(--border)); }
.card h3 { margin: 0 0 .35em; font-size: 1.12rem; }
.card p { margin: 0; color: var(--text-soft); font-size: .96rem; }
.card a.stretched::after { content: ""; position: absolute; inset: 0; }
.card.link { position: relative; }
.card .kicker { font-size: .78rem; font-weight: 700; text-transform: uppercase; letter-spacing: .05em; color: var(--brand-ink); }

/* ---------- Feature list ---------- */
.features { display: grid; grid-template-columns: repeat(3,1fr); gap: 18px; list-style: none; padding: 0; margin: 0; }
.features li {
  background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 20px; margin: 0;
}
.features .ico {
  display: inline-grid; place-items: center; width: 44px; height: 44px; margin-bottom: 12px;
  border-radius: 12px; background: var(--note-bg); color: var(--brand-ink); font-size: 1.4rem;
}
.features h3 { margin: 0 0 .3em; font-size: 1.08rem; }
.features p { margin: 0; color: var(--text-soft); font-size: .95rem; }

/* ---------- Steps ---------- */
.steps { list-style: none; counter-reset: step; padding: 0; margin: 1.2em 0; }
.steps > li {
  position: relative; padding: 4px 0 18px 56px; margin: 0;
  border-left: 2px solid var(--border); margin-left: 17px;
}
.steps > li:last-child { border-left-color: transparent; padding-bottom: 0; }
.steps > li::before {
  counter-increment: step; content: counter(step);
  position: absolute; left: -18px; top: 0; width: 34px; height: 34px;
  display: grid; place-items: center; border-radius: 50%;
  background: var(--gradient); color: #fff; font-weight: 800; font-size: .95rem;
  box-shadow: 0 4px 10px rgba(37,99,235,.3);
}
.steps > li h3 { margin: 2px 0 .3em; font-size: 1.1rem; }
.steps > li p:last-child { margin-bottom: 0; }

/* ---------- Tables ---------- */
.table-wrap { overflow-x: auto; margin: 1.2em 0; border: 1px solid var(--border); border-radius: var(--radius); }
table { width: 100%; border-collapse: collapse; font-size: .96rem; }
caption { caption-side: top; text-align: left; color: var(--text-mut); font-size: .88rem; padding: 10px 14px; }
th, td { padding: 12px 14px; text-align: left; border-bottom: 1px solid var(--border); vertical-align: top; }
thead th { background: var(--bg-soft); font-weight: 700; color: var(--text); white-space: nowrap; }
tbody tr:last-child td { border-bottom: none; }
tbody tr:hover { background: var(--bg-soft); }
.yes { color: #16a34a; font-weight: 700; }
.no { color: #dc2626; font-weight: 700; }

/* ---------- Callouts ---------- */
.note, .tip, .warn {
  border: 1px solid var(--note-bd); background: var(--note-bg);
  border-radius: var(--radius-sm); padding: 14px 18px; margin: 1.2em 0;
}
.note { border-color: var(--note-bd); background: var(--note-bg); }
.tip { border-color: var(--tip-bd); background: var(--tip-bg); }
.warn { border-color: var(--warn-bd); background: var(--warn-bg); }
.note p:last-child, .tip p:last-child, .warn p:last-child { margin-bottom: 0; }
.note strong, .tip strong, .warn strong { display: inline-block; margin-right: .3em; }

/* ---------- FAQ ---------- */
.faq { margin: 1em 0; }
.faq-item { border: 1px solid var(--border); border-radius: var(--radius-sm); padding: 4px 20px; margin-bottom: 12px; background: var(--bg-card); }
.faq-item h3 { font-size: 1.08rem; margin: 16px 0 .2em; }
.faq-item p:last-child { margin-bottom: 16px; }

/* ---------- E-E-A-T: byline + sources ---------- */
.byline { font-size: .9rem; color: var(--text-mut); margin: 0 0 1.4em; padding-bottom: 1.1em;
  border-bottom: 1px solid var(--border); display: flex; flex-wrap: wrap; gap: .35em .8em; align-items: center; }
.byline a { color: var(--text-soft); font-weight: 600; }
.byline time { color: var(--text); font-weight: 600; }
.sources ul { list-style: none; padding: 0; }
.sources li { padding: 9px 0 9px 26px; border-bottom: 1px dashed var(--border); position: relative; font-size: .95rem; }
.sources li:last-child { border-bottom: none; }
.sources li::before { content: "🔗"; position: absolute; left: 0; top: 8px; font-size: .9rem; }
.sources a[target="_blank"]::after { content: "↗"; font-size: .8em; margin-left: .25em; color: var(--text-mut); }

/* ---------- Pills / tags / rating ---------- */
.pills { display: flex; flex-wrap: wrap; gap: 8px; padding: 0; list-style: none; margin: 1em 0; }
.pill { display: inline-block; padding: 5px 12px; border-radius: 999px; background: var(--bg-soft); border: 1px solid var(--border); font-size: .85rem; color: var(--text-soft); font-weight: 600; }
.rating { display: inline-flex; align-items: center; gap: .4em; font-weight: 700; }
.rating .stars { color: #f59e0b; letter-spacing: 1px; }

/* ---------- Spec list ---------- */
.specs { display: grid; grid-template-columns: max-content 1fr; gap: 0 18px; margin: 1em 0; }
.specs dt { font-weight: 700; padding: 8px 0; border-bottom: 1px solid var(--border); color: var(--text-soft); }
.specs dd { margin: 0; padding: 8px 0; border-bottom: 1px solid var(--border); }

/* ---------- Section heading block ---------- */
.section-head { max-width: 720px; margin-bottom: 22px; }
.section-head h2 { margin-top: 0; }
.section-head p { color: var(--text-soft); margin-bottom: 0; }
.center { text-align: center; margin-inline: auto; }

/* ---------- Download box ---------- */
.download-box {
  background: var(--gradient); color: #fff; border-radius: var(--radius);
  padding: 26px; box-shadow: var(--shadow);
}
.download-box h2, .download-box h3 { color: #fff; margin-top: 0; }
.download-box p { color: rgba(255,255,255,.92); }
.download-box .btn-primary { background: #fff; color: var(--brand-ink); box-shadow: 0 8px 20px rgba(0,0,0,.18); }
.download-box .meta { font-size: .85rem; color: rgba(255,255,255,.85); margin-top: 10px; }

/* ---------- Footer ---------- */
.site-footer { background: var(--bg-soft); border-top: 1px solid var(--border); margin-top: 50px; }
.footer-grid { display: grid; grid-template-columns: 1.4fr repeat(5, 1fr); gap: 28px; padding: 44px 0 30px; }
.footer-brand .brand { margin-bottom: 12px; }
.footer-brand p { color: var(--text-soft); font-size: .92rem; max-width: 36ch; }
.footer-col h3 { font-size: .95rem; margin: 0 0 12px; }
.footer-col ul { list-style: none; margin: 0; padding: 0; }
.footer-col li { margin: 0; }
.footer-col a { display: block; padding: 5px 0; color: var(--text-soft); font-size: .92rem; }
.footer-col a:hover { color: var(--brand-ink); text-decoration: none; }
.footer-bottom { border-top: 1px solid var(--border); padding: 18px 0; display: flex; flex-wrap: wrap; gap: 10px; justify-content: space-between; color: var(--text-mut); font-size: .86rem; }
.footer-bottom .disclaimer { max-width: 70ch; }

/* ---------- Utilities ---------- */
.muted { color: var(--text-mut); }
.mt0 { margin-top: 0; } .mb0 { margin-bottom: 0; }
.tac { text-align: center; }
.nowrap { white-space: nowrap; }

/* ---------- Responsive ---------- */
@media (max-width: 940px) {
  .layout { grid-template-columns: 1fr; }
  .sidebar { position: static; }
  .grid-4 { grid-template-columns: repeat(2,1fr); }
  .features { grid-template-columns: repeat(2,1fr); }
  .footer-grid { grid-template-columns: 1fr 1fr; gap: 24px; }
}
@media (max-width: 860px) {
  .nav-toggle { display: inline-grid; }
  .nav-links {
    position: fixed; inset: 62px 0 auto 0; flex-direction: column; align-items: stretch;
    gap: 2px; background: var(--bg); border-bottom: 1px solid var(--border);
    padding: 12px 16px 18px; box-shadow: var(--shadow);
    transform: translateY(-130%); transition: transform .22s ease; visibility: hidden;
  }
  .nav-links.open { transform: translateY(0); visibility: visible; }
  .nav-links a { padding: 12px 10px; font-size: 1.02rem; border-radius: 10px; }
}
@media (max-width: 720px) {
  body { font-size: 16px; }
  .grid-2, .grid-3, .grid-4, .features { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .specs { grid-template-columns: 1fr; gap: 0; }
  .specs dt { border-bottom: none; padding-bottom: 0; }
}
@media (max-width: 460px) {
  .footer-grid { grid-template-columns: 1fr; }
  .cta-row .btn { width: 100%; justify-content: center; }
}

/* ---------- Motion / print ---------- */
@media (prefers-reduced-motion: reduce) {
  * { animation: none !important; transition: none !important; scroll-behavior: auto !important; }
}
@media print {
  .site-header, .site-footer, .sidebar, .cta-row, .nav-toggle { display: none !important; }
  body { font-size: 12pt; }
  .layout { grid-template-columns: 1fr; }
}