:root {
  --bg: #F3F3F3;
  --panel: #FFFFFF;
  --panel-2: #EAEAEA;
  --line: #DCDCDC;
  --accent: #11908E;
  --accent-dark: #0B6F6E;
  --ink: #0B5E60;
  --text: #1F2328;
  --muted: #62666D;
  --success: #2FA36B;
  --warn: #E59A2E;
  --error: #D9534F;
  --success-ink: #17643E;
  --warn-ink: #795011;
  --error-ink: #A02F2B;
  --dusk: #7B6FE0;
  --dusk-ink: #5146C2;
  --sand: #FF8A4C;
  --sand-ink: #B4501B;
  --sky-top: #CFE8F8;
  --sky-bottom: #E4F5F3;
  --sky-line: #B9D9E6;
  --chip-bg: #EEF8FB;
  --cloud: #FFFFFF;
  --snow: #FFFFFF;
  --mtn-back: #C2DEE7;
  --mtn-front: #A8CDD6;
  --hill-1: #C6ECE3;
  --hill-2: #ABE1D5;
  --hill-3: #90D4C6;
  --hill-4: #6CC2B3;
  --sea: #BDE8EB;
  --bush: #0B6F6E;
  --bush-2: #2C978D;
  --sandbar: #5BB5AA;
  --capsule-shade: #8CC6C0;
  --teal-soft: #E0F2EE;
  --dusk-soft: #EEEBFB;
  --sand-soft: #FFF0E7;
  --font-display: 'Inter', 'Noto Sans SC', 'Noto Sans JP', 'Noto Sans KR', 'PingFang SC', 'Microsoft YaHei', system-ui, sans-serif;
  --font-body: 'Inter', 'Noto Sans SC', 'Noto Sans JP', 'Noto Sans KR', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', system-ui, sans-serif;
  --font-mono: 'JetBrains Mono', ui-monospace, 'SFMono-Regular', Menlo, Consolas, monospace;
  --fs-xs: 12px;
  --fs-sm: 13px;
  --fs-label: 14px;
  --fs-nav: 15px;
  --fs-body: 16px;
  --fs-brand: 18px;
  --fs-lead: 20px;
  --fs-h3: 22px;
  --fs-h2: 32px;
  --fs-next: 28px;
  --fs-h1: clamp(34px, 3.1vw, 44px);
  --weight-normal: 400;
  --weight-strong: 600;
  --tracking-title: -0.02em;
  --tracking-small: -0.01em;
  --leading-body: 1.6;
  --leading-title: 1.12;
  --r-card: 24px;
  --r-container: 32px;
  --r-pill: 999px;
  --r-tile: 12px;
  --r-round: 50%;
  --gutter: 48px;
  --content-width: 1280px;
  --reading-width: 800px;
  --header-height: 76px;
  --section-space: 88px;
  --motion-fast: 180ms;
  --motion-reveal: 600ms;
  --focus-width: 3px;
}
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; scroll-padding-top: 96px; }
html.nav-open { overflow: hidden; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-body);
  font-size: var(--fs-body);
  line-height: var(--leading-body);
  -webkit-font-smoothing: antialiased;
}
img, svg { max-width: 100%; }
img { display: block; height: auto; }
button, input, select, textarea { font: inherit; }
button, a { -webkit-tap-highlight-color: transparent; }
button { cursor: pointer; }
button:disabled { cursor: not-allowed; }
a { color: var(--accent-dark); text-underline-offset: .2em; }
a:hover { color: var(--ink); }
:focus-visible { outline: var(--focus-width) solid var(--ink); outline-offset: 4px; }
[hidden] { display: none !important; }
h1, h2, h3, h4 {
  font-family: var(--font-display);
  font-weight: var(--weight-normal);
  color: var(--ink);
  text-wrap: balance;
  overflow-wrap: break-word;
}
h1 { font-size: var(--fs-h1); line-height: var(--leading-title); letter-spacing: var(--tracking-title); }
h2 { font-size: var(--fs-h2); line-height: 1.2; letter-spacing: var(--tracking-small); }
h3 { font-size: var(--fs-h3); line-height: 1.35; }
p { margin-block: 0 1em; }
strong { font-weight: var(--weight-strong); }
code, pre, kbd, samp { font-family: var(--font-mono); }
code { overflow-wrap: anywhere; }
pre {
  max-width: 100%;
  min-width: 0;
  overflow-x: auto;
  padding: 24px;
  border: 1px solid var(--line);
  border-radius: var(--r-tile);
  background: var(--panel-2);
  color: var(--text);
  font-size: var(--fs-label);
  tab-size: 2;
}
pre code { overflow-wrap: normal; white-space: pre; }
blockquote { margin-inline: 0; }
hr { border: 0; border-top: 1px solid var(--line); margin-block: 32px; }
ul, ol { padding-inline-start: 1.5em; }
li + li { margin-top: .4em; }
.wrap {
  width: 100%;
  max-width: calc(var(--content-width) + var(--gutter) * 2);
  margin-inline: auto;
  padding-inline: var(--gutter);
}
.reading { max-width: calc(var(--reading-width) + var(--gutter) * 2); }
.section { padding-top: var(--section-space); padding-bottom: var(--section-space); }
.section--alternate { background: var(--panel-2); color: var(--text); }
.section--wave { position: relative; overflow-x: clip; }
.section-wave { display: block; width: 100%; height: 64px; fill: var(--bg); }
.grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 24px; }
.grid > *, .wrap > *, .prose > *, .panel > *, .card > * { min-width: 0; }
.panel, .card {
  background: var(--panel);
  color: var(--text);
  border-radius: var(--r-container);
  padding: 40px;
}
.card { border-radius: var(--r-card); padding: 28px; }
.card h3, .panel h2 { margin-top: 0; }
.card__meta, .muted { color: var(--muted); }
.card__link { text-decoration: none; }
.prose { overflow-wrap: break-word; }
.prose h2 { margin-top: 2.2em; }
.prose h3 { margin-top: 1.6em; }
.prose p, .prose li { line-height: 1.85; }
.prose img { max-width: 100%; }
.prose :is(div, section, figure) { min-width: 0; max-width: 100%; }
.prose figure { margin-inline: 0; }
.keep { white-space: nowrap; }
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip-path: inset(50%);
  white-space: nowrap;
  border: 0;
}
.cta { display: flex; flex-wrap: wrap; gap: 14px; margin-top: 32px; }
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  min-height: 52px;
  max-width: 100%;
  padding: 12px 28px;
  border: 1.5px solid transparent;
  border-radius: var(--r-pill);
  font-family: var(--font-body);
  font-size: var(--fs-body);
  line-height: 1.25;
  text-align: center;
  text-decoration: none;
  transition: background var(--motion-fast), color var(--motion-fast);
}
.btn svg, .icon {
  width: 18px;
  height: 18px;
  flex-shrink: 0;
  fill: none;
  stroke: currentColor;
  stroke-width: 2;
  stroke-linecap: round;
  stroke-linejoin: round;
}
.btn--primary { background: var(--accent); color: var(--panel); }
.btn--primary:hover, .btn--primary.is-hover { background: var(--accent-dark); color: var(--panel); }
.btn--primary:active, .btn--primary.is-active { background: var(--ink); color: var(--panel); }
.btn--ghost { border-color: var(--accent); background: transparent; color: var(--accent-dark); }
.btn--ghost:hover, .btn--ghost.is-hover { background: var(--panel); color: var(--ink); }
.btn--ghost:active, .btn--ghost.is-active { background: var(--teal-soft); color: var(--ink); }
.btn:disabled, .btn[aria-disabled="true"] { background: var(--panel-2); border-color: var(--line); color: var(--muted); }
.btn.is-focus { outline: var(--focus-width) solid var(--ink); outline-offset: 4px; }
.topbar, #site-header { position: relative; z-index: 30; }
.topbar__in {
  display: flex;
  align-items: center;
  min-height: var(--header-height);
  gap: 16px;
  width: 100%;
  max-width: min(100%, calc(1280px + var(--gutter) * 2));
  margin-inline: auto;
  padding-inline: var(--gutter);
  position: relative;
}
.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--ink);
  text-decoration: none;
  flex-shrink: 0;
}
.brand__mark { width: 34px; height: 34px; flex-shrink: 0; }
.brand__name {
  font-family: var(--font-display);
  font-size: var(--fs-brand);
  font-weight: var(--weight-normal);
  letter-spacing: var(--tracking-small);
}
.nav { min-width: 0; margin-left: auto; }
.nav__list {
  display: flex;
  align-items: center;
  list-style: none;
  margin: 0;
  padding: 0;
  gap: 2px;
}
.nav__list li { margin: 0; }
.nav__link {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 8px 14px;
  border-radius: var(--r-pill);
  font-size: var(--fs-nav);
  color: var(--text);
  text-decoration: none;
  white-space: nowrap;
}
.nav__link svg {
  width: 16px;
  height: 16px;
  fill: none;
  stroke: currentColor;
  stroke-width: 1.7;
  stroke-linecap: round;
  stroke-linejoin: round;
  flex-shrink: 0;
}
.nav__link:hover { color: var(--accent-dark); }
.nav__link[aria-current="page"] { background: var(--panel); color: var(--accent-dark); }
.header-tools { display: flex; align-items: center; gap: 8px; flex-shrink: 0; }
.language { position: relative; }
.lang {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 7px;
  min-height: 38px;
  padding: 8px 14px;
  border: 1px solid var(--sky-line);
  border-radius: var(--r-pill);
  background: var(--chip-bg);
  color: var(--text);
  font-size: var(--fs-label);
  white-space: nowrap;
  text-decoration: none;
}
.lang svg { width: 15px; height: 15px; fill: none; stroke: currentColor; stroke-width: 1.7; flex-shrink: 0; }
.lang:hover { background: var(--panel); color: var(--text); }
.lang__caret { color: var(--muted); font-size: var(--fs-xs); }
.lang__short { display: none; }
.language__menu {
  position: absolute;
  top: calc(100% + 8px);
  right: 0;
  min-width: 180px;
  padding: 8px;
  list-style: none;
  margin: 0;
  border: 1px solid var(--line);
  border-radius: var(--r-tile);
  background: var(--panel);
  color: var(--text);
}
.language__menu li { margin: 0; }
.language__menu a { display: block; padding: 10px 12px; min-height: 44px; text-decoration: none; border-radius: var(--r-tile); }
.language__menu a:hover, .language__menu a[aria-current] { background: var(--bg); color: var(--ink); }
.menu-toggle {
  display: none;
  align-items: center;
  justify-content: center;
  min-width: 44px;
  min-height: 44px;
  border: 1px solid var(--sky-line);
  border-radius: var(--r-pill);
  background: var(--panel);
  color: var(--ink);
}
.menu-toggle svg { width: 20px; height: 20px; fill: none; stroke: currentColor; stroke-width: 1.7; }
.mobile-drawer { display: none; }
.nav-veil { position: fixed; inset: var(--header-height) 0 0; z-index: 20; border: 0; background: var(--text); color: var(--panel); opacity: .22; }
.site-footer { padding-top: 64px; padding-bottom: 32px; border-top: 1px solid var(--line); background: var(--panel-2); color: var(--text); }
.footer-grid { display: grid; grid-template-columns: 1.4fr 1fr 1.3fr 1fr; gap: 40px; }
.footer-grid > * { min-width: 0; }
.footer-intro { margin-top: 20px; color: var(--muted); max-width: 24em; }
.footer-title { font-size: var(--fs-body); color: var(--ink); margin-top: 0; margin-bottom: 16px; }
.footer-list { list-style: none; padding: 0; margin: 0; }
.footer-list a { display: inline-block; padding-block: 4px; text-decoration: none; color: var(--muted); overflow-wrap: anywhere; }
.footer-list a:hover { color: var(--ink); }
.footer-bottom { margin-top: 40px; padding-top: 24px; border-top: 1px solid var(--line); color: var(--muted); font-size: var(--fs-sm); }
.reveal { opacity: 1; transform: none; }
.reveal.is-observed { opacity: 0; transform: translateY(16px); transition: opacity var(--motion-reveal), transform var(--motion-reveal); }
.reveal.shown { opacity: 1; transform: none; }

/* 已确认的浅色首屏 */
.stage { position: relative; height: 860px; overflow: hidden; background: linear-gradient(180deg, var(--sky-top) 0%, var(--sky-bottom) 100%); color: var(--text); }
.scene { position: absolute; inset: 0; width: 100%; height: 100%; max-width: none; overflow: visible; z-index: 0; }
.hero { position: relative; z-index: 1; padding-top: 118px; }
.hero__copy { width: 620px; max-width: 100%; }
.eyebrow { display: inline-flex; align-items: center; gap: 10px; margin: 0; padding: 6px 14px 6px 12px; border-radius: var(--r-pill); background: var(--panel); color: var(--muted); font-size: var(--fs-sm); line-height: 18px; }
.eyebrow__dot { position: relative; width: 8px; height: 8px; border-radius: var(--r-round); background: var(--accent); flex-shrink: 0; }
.eyebrow__dot::after { content: ""; position: absolute; inset: -4px; border-radius: var(--r-round); background: var(--accent); opacity: .2; }
.hero__title { margin: 26px 0 0; font-size: var(--fs-h1); font-weight: var(--weight-normal); line-height: var(--leading-title); letter-spacing: var(--tracking-title); color: var(--ink); }
.hero__line { display: block; white-space: nowrap; }
.hero__key { font-style: normal; color: var(--accent); }
.hero__lead { margin: 28px 0 0; max-width: 36em; font-size: var(--fs-body); line-height: 1.75; color: var(--text); }
.hero__lead strong { color: var(--ink); }
.chips { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 22px; }
.chip { display: inline-block; max-width: 100%; padding: 5px 12px; border: 1px solid var(--sky-line); border-radius: var(--r-pill); background: var(--chip-bg); color: var(--ink); font-size: var(--fs-sm); line-height: 18px; text-decoration: none; overflow-wrap: anywhere; }
.chip:hover { border-color: var(--accent); color: var(--accent-dark); }
.platforms { display: flex; align-items: center; flex-wrap: wrap; gap: 14px 22px; margin-top: 34px; padding-top: 20px; border-top: 1px solid var(--sky-line); }
.platforms__label { font-size: var(--fs-sm); color: var(--muted); }
.platforms__list { display: flex; flex-wrap: wrap; gap: 12px 22px; list-style: none; margin: 0; padding: 0; }
.platforms__list li { margin: 0; }
.plat { display: inline-flex; align-items: center; gap: 9px; color: var(--text); font-size: var(--fs-label); text-decoration: none; }
.plat__badge { display: grid; place-items: center; width: 34px; height: 34px; border-radius: var(--r-round); background: var(--panel); color: var(--ink); flex-shrink: 0; }
.plat__badge svg { width: 17px; height: 17px; display: block; fill: currentColor; }
.plat__badge .plat__tux { width: 15px; height: 17px; }
.plat:hover { color: var(--accent-dark); }
.plat:hover .plat__badge { background: var(--accent); color: var(--panel); }
.f-cloud { fill: var(--cloud); }
.f-mtn-back { fill: var(--mtn-back); }
.f-mtn-front { fill: var(--mtn-front); }
.f-snow { fill: var(--snow); }
.f-hill1 { fill: var(--hill-1); }
.f-hill2 { fill: var(--hill-2); }
.f-hill3 { fill: var(--hill-3); }
.f-hill4 { fill: var(--hill-4); }
.f-sea { fill: var(--sea); }
.f-bush { fill: var(--bush); }
.f-bush2 { fill: var(--bush-2); }
.f-sandbar { fill: var(--sandbar); }
.f-bg { fill: var(--bg); }
.spring { fill: var(--snow); }
.spring-core { fill: var(--sky-top); }
.spring-ring { fill: none; stroke: var(--snow); stroke-width: 1.5; opacity: .85; }
.spring-ring--far { opacity: .45; }
.river { fill: none; stroke-linecap: round; stroke-linejoin: round; }
.river--main, .river--proxy { stroke: var(--accent); }
.river--direct { stroke: var(--dusk); }
.river--block { stroke: var(--sand); }
.plume--proxy { fill: var(--accent); opacity: .22; }
.plume--direct { fill: var(--dusk); opacity: .22; }
.plume--block { fill: var(--sand); opacity: .24; }
.ripple { fill: none; stroke: var(--panel); stroke-width: 2; stroke-linecap: round; opacity: .75; }
.leader { fill: none; stroke: var(--panel); stroke-width: 1.5; stroke-dasharray: 3 5; stroke-linecap: round; opacity: .95; }
.buoy-ring { fill: var(--panel); opacity: .85; }
.buoy-pole { stroke: var(--ink); stroke-width: 2; stroke-linecap: round; }
.fill-proxy { fill: var(--accent); }
.fill-direct { fill: var(--dusk); }
.fill-block { fill: var(--sand); }
.pill { fill: var(--panel); }
.pill-shade { fill: var(--capsule-shade); opacity: .55; }
.cap-t { font-family: var(--font-mono); font-size: var(--fs-xs); white-space: pre; }
.tx-ink { fill: var(--text); }
.tx-mute { fill: var(--muted); }
.tx-proxy { fill: var(--accent-dark); }
.tx-direct { fill: var(--dusk-ink); }
.tx-block { fill: var(--sand-ink); }
.label-t { font-family: var(--font-mono); font-size: var(--fs-xs); fill: var(--ink); }
.bob { animation: delta-bob 3.6s ease-in-out infinite alternate; }
.bob--2 { animation-duration: 3.2s; animation-delay: -1.2s; }
.bob--3 { animation-duration: 4s; animation-delay: -2.4s; }
@keyframes delta-bob { from { transform: translateY(0); } to { transform: translateY(-3px); } }
.next { background: var(--bg); color: var(--text); padding-top: 10px; padding-bottom: 88px; }
.next__panel { background: var(--panel); color: var(--text); border-radius: var(--r-container); padding: 26px 40px 34px; }
.next__kicker { display: inline-flex; align-items: center; gap: 8px; margin: 0; font-size: var(--fs-sm); color: var(--accent-dark); }
.next__kicker::before { content: ""; width: 6px; height: 6px; border-radius: var(--r-round); background: var(--accent); flex-shrink: 0; }
.next__title { margin: 10px 0 0; font-size: var(--fs-next); line-height: 1.2; letter-spacing: var(--tracking-small); }
.next__text { margin: 12px 0 0; color: var(--muted); max-width: 44em; }
.next__link { display: inline-block; margin-top: 14px; text-decoration: none; }
@media (max-width: 1279px) {
  .nav--desktop { display: none; }
  .header-tools { margin-left: auto; }
  .menu-toggle { display: inline-flex; }
  .mobile-drawer:not([hidden]) {
    display: block;
    position: absolute;
    top: 100%;
    left: var(--gutter);
    right: var(--gutter);
    padding: 16px;
    max-height: calc(100dvh - var(--header-height) - 16px);
    overflow-y: auto;
    overscroll-behavior: contain;
    border: 1px solid var(--line);
    border-radius: var(--r-card);
    background: var(--panel);
    color: var(--text);
    z-index: 32;
  }
  .mobile-drawer ul { display: block; list-style: none; margin: 0; padding: 0; }
  .mobile-drawer li { margin: 0; }
  .mobile-drawer a { display: flex; align-items: center; width: 100%; min-height: 46px; padding: 12px 16px; text-decoration: none; }
  .mobile-drawer__languages { margin-top: 12px; padding-top: 12px; border-top: 1px solid var(--line); }
}
@media (max-width: 1180px) {
  .stage { height: auto; display: flex; flex-direction: column; }
  .scene { position: relative; inset: auto; order: 3; width: 195%; max-width: none; height: auto; margin-left: -95%; margin-top: 12px; }
  .hero { padding-top: 40px; }
  .hero__line { white-space: normal; }
  .footer-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (max-width: 768px) {
  :root { --gutter: 24px; --section-space: 56px; --fs-h1: clamp(24px, 4vw, 30px); --fs-h2: 28px; }
  .grid { grid-template-columns: minmax(0, 1fr); }
  .panel { padding: 28px; }
}
@media (max-width: 640px) {
  :root { --gutter: 20px; --fs-h1: clamp(24px, 7.2vw, 30px); --fs-h2: 26px; }
  .brand__name { font-size: var(--fs-nav); }
  .topbar__in { gap: 8px; }
  .lang { padding-inline: 10px; }
  .lang__full { display: none; }
  .lang__short { display: inline; }
  .hero__title { margin-top: 20px; }
  .btn { min-height: 48px; padding: 12px 22px; font-size: var(--fs-nav); }
  .platforms { gap: 12px; }
  .platforms__list { gap: 12px 18px; }
  .next__panel { padding: 22px 22px 28px; border-radius: var(--r-card); }
  .next__title { font-size: var(--fs-h3); }
  .panel, .card { padding: 22px; }
  .footer-grid { grid-template-columns: minmax(0, 1fr); gap: 28px; }
  .tilt, [data-tilt] { transform: none !important; }
  .chips { flex-direction: row; flex-wrap: wrap; }
}
@media (max-width: 359px) {
  .brand__name { font-size: var(--fs-sm); }
  .brand { gap: 6px; }
  .brand__mark { width: 30px; height: 30px; }
  .header-tools { gap: 4px; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation: none !important; transition: none !important; }
  .reveal.is-observed { opacity: 1; transform: none; }
}