:root {
  --bg: #000000;
  --bg-panel: #0C0C0D;
  --bg-panel-2: #161618;
  --border: #26262A;
  --border-strong: #34343A;
  --accent: #2F80FF;
  --accent-dark: #1A5FD6;
  --accent-soft: #8FB9FF;
  --text: #F2F2F3;
  --text-muted: #8E8E93;
  --text-faint: #5C5C63;
  --white: #FFFFFF;
  --ink: #000000;
  --success: #3FCF8E;
  --warn: #F5B544;
  --error: #F2545B;
  --canvas: #02060F;
  --canvas-2: #051128;
  --canvas-bar: rgba(47,128,255,.07);
  --canvas-lit: rgba(47,128,255,.18);
  --glow-strong: rgba(47,128,255,.55);
  --glow: rgba(47,128,255,.32);
  --glow-faint: rgba(47,128,255,.12);
  --glow-line: rgba(47,128,255,.42);
  --glow-dash: rgba(143,185,255,.45);
  --sel-fill: rgba(47,128,255,.13);
  --clear: transparent;
  --veil: rgba(0,0,0,.75);
  --shadow-float: 0 14px 32px rgba(0,0,0,.65), 0 2px 6px rgba(0,0,0,.5);
  --r-xl: 28px;
  --r-lg: 18px;
  --r-md: 14px;
  --r-sm: 10px;
  --r-xs: 6px;
  --r-selection: 3px;
  --r-label: 4px;
  --r-mobile: 22px;
  --r-pill: 999px;
  --font-display: "Inter", "Noto Sans SC", "PingFang SC", "Microsoft YaHei", system-ui, sans-serif;
  --font-body: "Inter", "Noto Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui, sans-serif;
  --font-mono: "JetBrains Mono", ui-monospace, "SFMono-Regular", Menlo, Consolas, monospace;
  --gutter: 40px;
  --content-width: 1280px;
  --header-height: 64px;
  --section-space: 96px;
  --ease: 200ms ease;
  --reveal-time: 600ms;
  --tab-duration: 7000ms;
}

*, *::before, *::after { box-sizing: border-box; }
html {
  background: var(--bg);
  color: var(--text);
  scroll-behavior: smooth;
  scroll-padding-top: 24px;
}
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}
html.nav-open { overflow: hidden; }
[hidden] { display: none !important; }
img, svg { vertical-align: middle; }
img { max-width: 100%; height: auto; }
button, input, select, textarea { font: inherit; }
button, a { -webkit-tap-highlight-color: var(--clear); }
button { cursor: pointer; }
button:disabled { cursor: not-allowed; }
a { color: var(--accent-soft); text-underline-offset: .22em; }
a:hover { color: var(--text); }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; border-radius: var(--r-xs); }
::selection { background: var(--accent-dark); color: var(--white); }
h1, h2, h3, h4 {
  font-family: var(--font-display);
  font-weight: 400;
  color: var(--text);
  text-wrap: balance;
  overflow-wrap: break-word;
}
h1 { font-size: clamp(34px, 1rem + 2.6vw, 48px); line-height: 1.12; letter-spacing: -.005em; }
h2 { font-size: clamp(26px, 2.7vw, 36px); line-height: 1.25; }
h3 { font-size: 22px; line-height: 1.4; }
p { color: var(--text-muted); }
strong { color: var(--text); font-weight: 500; }
code, pre, kbd, samp { font-family: var(--font-mono); }
code { overflow-wrap: anywhere; }
pre {
  max-width: 100%;
  overflow-x: auto;
  padding: 24px;
  background: var(--bg);
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: var(--r-md);
  font-size: 13px;
  line-height: 1.8;
  tab-size: 2;
}
pre code { white-space: pre; overflow-wrap: normal; word-break: normal; }
blockquote { margin-inline: 0; }
.wrap {
  width: 100%;
  max-width: var(--content-width);
  margin-inline: auto;
  padding-inline: var(--gutter);
}
.section { padding-top: var(--section-space); padding-bottom: var(--section-space); }
.section + .section { padding-top: 0; }
.section-heading { margin: 0 0 28px; }
.section-intro { max-width: 720px; margin-bottom: 32px; }
.prose, .article-body { min-width: 0; max-width: 820px; }
.prose p, .article-body p { line-height: 1.9; }
.prose h2, .article-body h2 { margin-top: 64px; }
.prose h3, .article-body h3 { margin-top: 36px; }
.prose li, .article-body li { color: var(--text-muted); margin-block: 8px; }
.prose > :first-child, .article-body > :first-child { margin-top: 0; }
.prose :is(div, section), .article-body :is(div, section) { min-width: 0; max-width: 100%; }
.nowrap { white-space: nowrap; }
.mono { font-family: var(--font-mono); }
.muted { color: var(--text-muted); }
.vh {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip-path: inset(50%);
  white-space: nowrap;
  border: 0;
}
.skip-link {
  position: fixed;
  top: 8px;
  left: var(--gutter);
  z-index: 100;
  padding: 10px 16px;
  transform: translateY(-160%);
  background: var(--white);
  color: var(--ink);
  border-radius: var(--r-sm);
}
.skip-link:focus { transform: none; }
.grid-two { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 24px; }
.grid-two > *, .opening-grid > *, .deck > *, .footer-grid > * { min-width: 0; }
.panel, .card {
  min-width: 0;
  padding: 28px;
  background: var(--bg-panel);
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: var(--r-xl);
}
.card h3 { margin-top: 0; }
.card > :last-child { margin-bottom: 0; }
.decorated, [data-hero-visual] { position: relative; overflow-x: clip; }
.btn-solid, .btn-dim, .btn-accent {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  min-height: 46px;
  padding: 10px 22px;
  max-width: 100%;
  font-size: 15px;
  font-weight: 500;
  line-height: 1.6;
  text-align: center;
  text-decoration: none;
  border: 1px solid var(--clear);
  border-radius: var(--r-md);
  transition: background-color var(--ease), border-color var(--ease);
}
.btn-solid { background: var(--white); color: var(--ink); }
.btn-solid:hover, .btn-solid.is-hover { background: var(--text); color: var(--ink); }
.btn-dim { background: var(--bg-panel-2); color: var(--text); border-color: var(--border); }
.btn-dim:hover, .btn-dim.is-hover { background: var(--bg-panel-2); color: var(--text); border-color: var(--border-strong); }
.btn-accent { background: var(--accent); color: var(--ink); }
.btn-accent:hover, .btn-accent.is-hover { background: var(--accent-soft); color: var(--ink); }
:is(.btn-solid, .btn-dim, .btn-accent):active { transform: translateY(1px); }
:is(.btn-solid, .btn-dim, .btn-accent):disabled,
:is(.btn-solid, .btn-dim, .btn-accent)[aria-disabled="true"] {
  background: var(--bg-panel-2);
  color: var(--text-muted);
  border-color: var(--border);
  cursor: not-allowed;
}
.is-focus { outline: 2px solid var(--accent); outline-offset: 3px; }
.btn-solid svg, .btn-dim svg, .btn-accent svg { width: 16px; height: 16px; flex-shrink: 0; }
.cta-row { display: flex; align-items: center; flex-wrap: wrap; gap: 12px; margin-top: 28px; }

/* 页头单独使用宽版心，正文仍保持批准稿的 1280px 外宽。 */
.topbar { position: relative; z-index: 40; height: var(--header-height); background: var(--bg); color: var(--text); }
.header-shell {
  max-width: min(100%, calc(1280px + var(--gutter) * 2));
  margin-inline: auto;
  padding-inline: var(--gutter);
  height: 100%;
  display: flex;
  align-items: center;
  gap: 32px;
}
.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  flex-shrink: 0;
  text-decoration: none;
  color: var(--text);
  font-size: 15px;
  font-weight: 500;
  letter-spacing: .01em;
}
.brand img { width: 28px; height: 28px; flex-shrink: 0; }
.desktop-nav { min-width: 0; margin-left: auto; }
.navline { display: flex; align-items: center; list-style: none; margin: 0; padding: 0; gap: 0; font-size: 14px; }
.navline li { display: flex; align-items: center; flex-shrink: 0; }
.navline li + li::before { content: "/"; margin-inline: 12px; color: var(--text-faint); font: 13px var(--font-mono); }
.navline a { display: inline-flex; align-items: center; padding: 6px 2px; color: var(--text-muted); text-decoration: none; white-space: nowrap; }
.navline a:hover, .navline a[aria-current="page"] { color: var(--text); }
.header-tools { display: flex; align-items: center; gap: 12px; flex-shrink: 0; }
.language-control { position: relative; }
.lang {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  min-height: 32px;
  padding: 4px 12px;
  font-size: 13px;
  color: var(--text);
  background: var(--bg-panel-2);
  border: 1px solid var(--border);
  border-radius: var(--r-sm);
  white-space: nowrap;
}
.lang svg { width: 14px; height: 14px; flex-shrink: 0; color: var(--text-muted); }
.lang-short { display: none; }
.lang .caret { color: var(--text-muted); font-size: 11px; }
.language-menu {
  position: absolute;
  top: calc(100% + 10px);
  right: 0;
  min-width: 180px;
  padding: 8px;
  background: var(--bg-panel);
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: var(--r-md);
  z-index: 44;
}
.language-menu a { display: flex; align-items: center; min-height: 44px; padding: 8px 12px; color: var(--text-muted); text-decoration: none; border-radius: var(--r-xs); }
.language-menu a:hover, .language-menu a[aria-current] { background: var(--bg-panel-2); color: var(--text); }
.menu-toggle { display: none; align-items: center; justify-content: center; min-width: 44px; min-height: 44px; padding: 8px; border: 1px solid var(--border); border-radius: var(--r-sm); background: var(--bg-panel-2); color: var(--text); }
.menu-toggle svg { width: 20px; height: 20px; flex-shrink: 0; }
.mobile-drawer {
  position: absolute;
  top: 100%;
  left: 0;
  right: 0;
  max-height: calc(100dvh - var(--header-height));
  overflow-y: auto;
  overscroll-behavior: contain;
  padding: 16px var(--gutter) 24px;
  background: var(--bg-panel);
  color: var(--text);
  border-bottom: 1px solid var(--border);
  z-index: 43;
}
.mobile-drawer ul { list-style: none; margin: 0; padding: 0; }
.mobile-drawer a { display: flex; align-items: center; width: 100%; min-height: 44px; padding: 10px 12px; color: var(--text-muted); text-decoration: none; }
.mobile-drawer a:hover, .mobile-drawer a[aria-current] { background: var(--bg-panel-2); color: var(--text); border-radius: var(--r-sm); }
.drawer-label { margin: 20px 12px 8px; font-size: 12px; color: var(--text-muted); }
.nav-veil { position: fixed; inset: var(--header-height) 0 0; z-index: 30; border: 0; background: var(--veil); color: var(--text); }

/* 批准稿首屏：自然高度，无入场或循环动画。 */
.opening { padding-top: 44px; overflow-x: clip; }
.opening-grid { display: grid; grid-template-columns: minmax(0,1fr) 384px; gap: 56px; align-items: end; }
.headline { margin: 0; font-size: clamp(1.75rem, 1rem + 2.6vw, 3rem); line-height: 1.12; }
.headline .row { display: block; }
.headline .dot { color: var(--text-faint); }
.fact-mono { margin-left: 14px; font-family: var(--font-mono); font-size: 13px; color: var(--text-muted); letter-spacing: .01em; }
.fact-mono b { color: var(--text); font-weight: 400; }
.os-row { display: flex; align-items: center; flex-wrap: wrap; gap: 22px; margin-top: 18px; min-height: 24px; }
.os-label { font-family: var(--font-mono); font-size: 12px; color: var(--text-muted); }
.os-row a { display: inline-flex; align-items: center; gap: 7px; font-size: 13px; color: var(--text-muted); text-decoration: none; }
.os-row a:hover { color: var(--text); }
.os-row svg { width: 15px; height: 15px; flex-shrink: 0; }
.lede { margin: 0; font-size: 15px; line-height: 1.75; color: var(--text-muted); }
.chipline { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 18px; }
.chipline a { display: inline-flex; align-items: center; gap: 6px; min-height: 26px; max-width: 100%; padding: 3px 11px; font-size: 12px; line-height: 1.5; color: var(--text-muted); text-decoration: none; background: var(--bg-panel); border: 1px solid var(--border); border-radius: var(--r-pill); overflow-wrap: anywhere; }
.chipline a::before { content: "#"; font-family: var(--font-mono); color: var(--accent-soft); flex-shrink: 0; }
.chipline a:hover { color: var(--text); border-color: var(--glow-line); }
.facts { margin-top: 36px; border-top: 1px solid var(--border); }
.facts dl { display: flex; flex-wrap: wrap; align-items: center; gap: 14px 44px; margin: 0; padding-block: 18px; font-family: var(--font-mono); font-size: 12.5px; }
.facts .item { display: flex; gap: 10px; align-items: baseline; }
.facts dt { color: var(--text-muted); }
.facts dd { margin: 0; color: var(--text); }

.site-footer { margin-top: 64px; border-top: 1px solid var(--border); background: var(--bg); color: var(--text); }
.footer-grid { display: grid; grid-template-columns: 1.35fr 1fr 1.25fr 1fr; gap: 36px; padding-top: 56px; padding-bottom: 48px; }
.footer-grid h2 { margin: 0 0 16px; font-size: 14px; line-height: 1.5; }
.footer-grid p { max-width: 300px; font-size: 13px; }
.footer-grid ul { list-style: none; margin: 0; padding: 0; }
.footer-grid li { margin-block: 8px; }
.footer-grid a:not(.brand) { color: var(--text-muted); font-size: 13px; text-decoration: none; }
.footer-grid a:hover { color: var(--text); }
.copyright { display: flex; justify-content: space-between; gap: 16px; flex-wrap: wrap; padding-top: 20px; padding-bottom: 24px; border-top: 1px solid var(--border); color: var(--text-muted); font-size: 12px; }
.copyright a { color: var(--text-muted); }
.reveal { opacity: 1; transform: none; }
html.reveal-ready .reveal:not(.shown) { opacity: 0; transform: translateY(16px); }
html.reveal-ready .reveal { transition: opacity var(--reveal-time) ease, transform var(--reveal-time) ease; }

@media (max-width: 1200px) {
  .desktop-nav { display: none; }
  .header-tools { margin-left: auto; }
  .menu-toggle { display: inline-flex; }
}
@media (min-width: 1201px) {
  .mobile-drawer, .nav-veil { display: none !important; }
}
@media (max-width: 1080px) {
  .opening-grid { grid-template-columns: 1fr; gap: 28px; align-items: start; }
  .footer-grid { grid-template-columns: repeat(2,minmax(0,1fr)); }
}
@media (max-width: 768px) {
  h1, .headline { font-size: clamp(24px, 4vw, 30px); }
}
@media (max-width: 640px) {
  :root { --gutter: 20px; --section-space: 64px; }
  .header-shell { gap: 12px; }
  .header-tools { margin-left: auto; gap: 8px; }
  .lang-full { display: none; }
  .lang-short { display: inline; }
  .brand { font-size: 14px; gap: 8px; }
  .grid-two { grid-template-columns: minmax(0,1fr); }
  .opening { padding-top: 28px; }
  .headline { font-size: clamp(26px,6.5vw,30px); }
  .fact-mono { margin-left: 0; width: 100%; }
  .os-row { gap: 12px 18px; }
  .panel, .card { padding: 20px; }
  .footer-grid { gap: 28px 20px; }
  .footer-brand { grid-column: 1 / -1; }
  .tilt, [data-tilt] { transform: none !important; }
}
@media (max-width: 360px) {
  :root { --gutter: 16px; }
  .brand { font-size: 13px; }
  .lang { padding-inline: 10px; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation: none !important; transition: none !important; }
  html.reveal-ready .reveal:not(.shown) { opacity: 1; transform: none; }
}