:root {
  --bg: #F2F2F2;
  --panel: #FFFFFF;
  --panel-2: #E8E8E8;
  --line: #D9D9D9;
  --accent: #EE8A2B;
  --accent-dark: #B35F0E;
  --teal: #3FB3A4;
  --teal-ink: #2E9C8E;
  --peri: #8B8BE8;
  --peri-ink: #5A5AC6;
  --text: #222326;
  --muted: #62646B;
  --success: #2E9C8E;
  --warn: #C98A12;
  --error: #D2474F;
  --sky-top: #D6EDF8;
  --sky-bottom: #E4F6F3;
  --cloud: #FFFFFF;
  --snow: #FFFFFF;
  --ridge: #D2E6EA;
  --peak-1: #C9DEE3;
  --peak-1-shade: #B5CFD5;
  --peak-2: #BED7DD;
  --peak-2-shade: #A8C6CD;
  --hill-1: #C9EEE7;
  --hill-2: #A3DFD5;
  --hill-3: #78CDBF;
  --bush-back: #3FB3A4;
  --bush-front: #2E9C8E;
  --river: #EEF9FD;
  --ripple: #FFFFFF;
  --rock: #6E868B;
  --post: #8FA4A8;
  --tint-orange: #FBE9D8;
  --tint-teal: #E0F3EF;
  --tint-peri: #EAEAFB;
  --clear: transparent;
  --font-display: "Inter", "Noto Sans SC", "PingFang SC", "Hiragino Sans GB", "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;
  --r-xs: 8px;
  --r-sm: 12px;
  --r-md: 18px;
  --r-lg: 28px;
  --r-pill: 999px;
  --r-round: 50%;
  --gutter: 40px;
  --wrap: 1360px;
  --reading: 840px;
  --head-content: 1280px;
  --hero-h: 860px;
  --head-h: 76px;
  --text-base: 16px;
  --text-small: 14px;
  --text-tiny: 12px;
  --title-1: clamp(34px, 3.4vw, 48px);
  --title-2: clamp(24px, 2.4vw, 32px);
  --title-3: 22px;
  --weight-normal: 400;
  --weight-medium: 500;
  --weight-strong: 600;
  --ease: .2s ease;
  --section-gap: 88px;
}
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; scroll-padding-top: 24px; }
html.nav-open { overflow: hidden; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-body);
  font-size: var(--text-base);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}
img, svg { max-width: 100%; vertical-align: middle; }
img { height: auto; }
button, input, select, textarea { font: inherit; }
button { cursor: pointer; }
a { color: var(--accent-dark); text-underline-offset: 4px; }
a:hover { text-decoration-thickness: 2px; }
button, a, summary { -webkit-tap-highlight-color: var(--clear); }
:focus-visible { outline: 2px solid var(--accent-dark); outline-offset: 3px; }
[hidden] { display: none !important; }
h1, h2, h3 { font-family: var(--font-display); font-weight: var(--weight-normal); text-wrap: balance; }
h1 { font-size: var(--title-1); line-height: 1.14; letter-spacing: -.01em; }
h2 { font-size: var(--title-2); line-height: 1.25; }
h3 { font-size: var(--title-3); line-height: 1.35; }
p { margin: 0 0 1em; }
strong { font-weight: var(--weight-strong); }
code, pre, kbd { font-family: var(--font-mono); }
code { overflow-wrap: anywhere; font-size: .9em; }
pre {
  max-width: 100%;
  min-width: 0;
  overflow-x: auto;
  padding: 20px;
  border: 1px solid var(--line);
  border-radius: var(--r-sm);
  background: var(--panel-2);
  color: var(--text);
  font-size: var(--text-small);
  line-height: 1.7;
}
pre code { font-size: inherit; white-space: pre; overflow-wrap: normal; word-break: normal; }
ul, ol { padding-left: 1.5em; }
hr { border: 0; border-top: 1px solid var(--line); margin-block: 32px; }
.grid > *, .card-grid > *, .head-row > *, .footer-grid > *, .feature-tabs > * { min-width: 0; }
.wrap {
  width: 100%;
  max-width: var(--wrap);
  margin-inline: auto;
  padding-inline: var(--gutter);
}
.reading { max-width: calc(var(--reading) + var(--gutter) * 2); }
.section { padding-top: var(--section-gap); padding-bottom: var(--section-gap); }
.section--alt { background: var(--panel-2); color: var(--text); border-radius: var(--r-lg); }
.section-title { margin-top: 0; margin-bottom: 16px; }
.section-intro { max-width: 42em; color: var(--muted); }
.page-main { padding-top: 52px; padding-bottom: var(--section-gap); }
.prose { min-width: 0; overflow-wrap: break-word; }
.prose h2 { margin-top: 2em; }
.prose h3 { margin-top: 1.6em; }
.prose li + li { margin-top: .5em; }
.prose p { line-height: 1.85; }
.prose img { max-width: 100%; }
.kw { white-space: nowrap; }
.muted { color: var(--muted); }
.mono { font-family: var(--font-mono); }
.vh {
  position: absolute;
  width: 1px;
  height: 1px;
  margin: -1px;
  padding: 0;
  overflow: hidden;
  clip-path: inset(50%);
  white-space: nowrap;
  border: 0;
}
.skip {
  position: fixed;
  left: 16px;
  top: -80px;
  z-index: 100;
  padding: 8px 14px;
  border-radius: var(--r-pill);
  border: 1px solid var(--line);
  background: var(--panel);
  color: var(--text);
  text-decoration: none;
}
.skip:focus { top: 12px; }
.panel, .card {
  min-width: 0;
  padding: 28px;
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  background: var(--panel);
  color: var(--text);
}
.panel--soft { background: var(--panel-2); color: var(--text); }
.card h3 { margin-top: 0; }
.card p:last-child { margin-bottom: 0; }
.card-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 24px; }
.btn {
  display: inline-flex;
  justify-content: center;
  align-items: center;
  gap: 10px;
  min-height: 50px;
  padding: 10px 24px;
  border-radius: var(--r-pill);
  border: 1px solid var(--clear);
  font-family: var(--font-body);
  font-size: var(--text-base);
  font-weight: var(--weight-medium);
  line-height: 1.4;
  text-decoration: none;
  transition: background-color var(--ease), color var(--ease), border-color var(--ease);
}
.btn svg { width: 18px; height: 18px; flex-shrink: 0; }
.btn--main { background: var(--accent); color: var(--text); }
.btn--main:hover, .btn--main.is-hover { background: var(--accent-dark); color: var(--panel); }
.btn--ghost { background: var(--panel); border-color: var(--line); color: var(--text); }
.btn--ghost:hover, .btn--ghost.is-hover { border-color: var(--accent); color: var(--accent-dark); }
.btn--text { background: var(--clear); color: var(--accent-dark); padding-inline: 12px; }
.btn:active, .btn.is-active { transform: translateY(1px); }
.btn.is-focus { outline: 2px solid var(--accent-dark); outline-offset: 3px; }
.btn:disabled, .btn[aria-disabled="true"] {
  background: var(--panel-2);
  border-color: var(--line);
  color: var(--muted);
  cursor: not-allowed;
  transform: none;
}
.cta-row { display: flex; align-items: center; flex-wrap: wrap; gap: 12px; margin-top: 24px; }
.tags { display: flex; flex-wrap: wrap; gap: 8px; margin: 0; padding: 0; list-style: none; }
.tag {
  display: inline-flex;
  align-items: center;
  min-height: 26px;
  max-width: 100%;
  padding: 3px 12px;
  border-radius: var(--r-pill);
  background: var(--panel);
  border: 1px solid var(--line);
  color: var(--muted);
  font-size: 12.5px;
  line-height: 1.4;
  overflow-wrap: anywhere;
}
.tag--mono { font-family: var(--font-mono); font-size: var(--text-tiny); color: var(--text); }
.site-head { position: relative; z-index: 30; background: var(--sky-top); color: var(--text); }
.site-head--hero { position: absolute; inset: 0 0 auto; background: var(--clear); color: var(--text); }
.head-row {
  position: relative;
  max-width: min(100%, calc(var(--head-content) + var(--gutter) * 2));
  min-height: var(--head-h);
  margin-inline: auto;
  padding-inline: var(--gutter);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}
.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--text);
  font-size: 17px;
  font-weight: var(--weight-medium);
  letter-spacing: .01em;
  text-decoration: none;
  flex-shrink: 0;
}
.brand-mark { width: 32px; height: 32px; flex-shrink: 0; }
.nav-dots { min-width: 0; margin-left: auto; }
.nav-dots ul { display: flex; align-items: center; list-style: none; margin: 0; padding: 0; }
.nav-dots li { display: flex; align-items: center; flex-shrink: 0; }
.nav-dots li + li::before { content: "·"; content: "·" / ""; margin-inline: 13px; color: var(--muted); font-size: 15px; }
.nav-dots a { position: relative; display: inline-block; padding-block: 6px; font-size: 15px; color: var(--text); text-decoration: none; white-space: nowrap; }
.nav-dots a:hover { color: var(--accent-dark); }
.nav-dots a[aria-current="page"]::after {
  content: "";
  position: absolute;
  left: 50%;
  bottom: -3px;
  width: 18px;
  height: 2px;
  transform: translateX(-50%);
  border-radius: var(--r-xs);
  background: var(--accent);
}
.head-tools { display: flex; align-items: center; gap: 12px; flex-shrink: 0; margin-left: 4px; }
.language-box { position: relative; }
.lang {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  min-height: 34px;
  padding: 5px 14px;
  border: 1px solid var(--line);
  border-radius: var(--r-pill);
  background: var(--panel);
  color: var(--text);
  font-size: var(--text-small);
  white-space: nowrap;
  text-decoration: none;
}
.lang:hover { border-color: var(--accent); }
.caret-down { color: var(--muted); font-size: 11px; }
.lang-short { display: none; }
.language-menu {
  position: absolute;
  top: calc(100% + 10px);
  right: 0;
  min-width: 172px;
  padding: 8px;
  border: 1px solid var(--line);
  border-radius: var(--r-md);
  background: var(--panel);
  color: var(--text);
  z-index: 34;
}
.language-menu a { display: flex; align-items: center; min-height: 44px; padding: 8px 12px; border-radius: var(--r-xs); color: var(--text); text-decoration: none; }
.language-menu a:hover, .language-menu a[aria-current="true"] { background: var(--bg); 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(--line);
  border-radius: var(--r-sm);
  background: var(--panel);
  color: var(--text);
}
.menu-toggle svg { width: 20px; height: 20px; flex-shrink: 0; }
.menu-drawer {
  position: absolute;
  inset: 100% 0 auto;
  padding: 16px var(--gutter) 24px;
  max-height: calc(100dvh - var(--head-h));
  overflow-y: auto;
  overscroll-behavior: contain;
  border-bottom: 1px solid var(--line);
  background: var(--panel);
  color: var(--text);
  z-index: 33;
}
.menu-drawer ul { list-style: none; padding: 0; margin: 0; }
.menu-drawer a { display: flex; align-items: center; width: 100%; min-height: 48px; padding: 10px 12px; color: var(--text); text-decoration: none; border-radius: var(--r-xs); }
.menu-drawer a:hover, .menu-drawer a[aria-current] { background: var(--bg); color: var(--text); }
.drawer-languages { border-top: 1px solid var(--line); margin-top: 12px; padding-top: 12px; }
.nav-veil { position: fixed; inset: var(--head-h) 0 0; z-index: 25; background: var(--bg); color: var(--text); opacity: .8; border: 0; }
.site-foot { padding-top: 64px; padding-bottom: 96px; 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: 32px; }
.footer-brand p { margin-top: 18px; max-width: 26em; color: var(--muted); font-size: var(--text-small); }
.footer-grid h2 { font-size: var(--text-base); font-weight: var(--weight-medium); margin: 0 0 16px; }
.footer-links { margin: 0; padding: 0; list-style: none; }
.footer-links a { display: inline-block; padding-block: 5px; color: var(--text); font-size: var(--text-small); text-decoration: none; }
.footer-links a:hover { color: var(--accent-dark); text-decoration: underline; }
.copyright { display: flex; justify-content: space-between; flex-wrap: wrap; gap: 12px; margin-top: 40px; padding-top: 20px; border-top: 1px solid var(--line); font-size: var(--text-small); color: var(--muted); }
.copyright p { margin: 0; }
.copyright a { color: var(--text); }
.reveal { opacity: 1; transform: none; }
.reveal-ready .reveal:not(.shown) { opacity: 0; transform: translateY(14px); }
.reveal-ready .reveal { transition: opacity .6s ease, transform .6s ease; }
.reveal.shown { opacity: 1; transform: none; }
.decor-section { position: relative; overflow-x: clip; }
.hero { position: relative; height: var(--hero-h); overflow: hidden; background: var(--sky-bottom); color: var(--text); }
.hero-visual { position: absolute; inset: 0; overflow: hidden; }
.valley { position: absolute; inset: 0; width: 100%; height: 100%; max-width: none; display: block; }
.hero .hero-inner { position: relative; z-index: 2; padding-top: 108px; }
.hero-copy { width: 560px; max-width: 100%; }
.hero h1 { margin: 18px 0 0; font-size: clamp(28px, 3.4vw, 48px); line-height: 1.14; }
.h1-line { display: block; }
.h1-kw { color: var(--accent-dark); }
.lead { margin: 16px 0 0; max-width: 31em; font-size: 16.5px; line-height: 1.7; color: var(--muted); }
.lead strong { color: var(--text); }
.platforms { display: flex; align-items: center; flex-wrap: wrap; gap: 24px; margin: 20px 0 0; padding: 0; list-style: none; }
.platforms a { display: inline-flex; align-items: center; gap: 8px; min-height: 26px; font-size: var(--text-small); color: var(--text); text-decoration: none; }
.platforms a:hover { color: var(--accent-dark); }
.pf-ic { width: 16px; height: 16px; flex-shrink: 0; color: var(--muted); }
.pf-ic--tux { width: 15px; height: 17px; }
.term { margin-top: 26px; width: 556px; max-width: 100%; background: var(--panel); color: var(--text); border: 1px solid var(--line); border-radius: var(--r-md); overflow: hidden; }
.term-bar { display: flex; align-items: center; gap: 7px; height: 36px; padding-inline: 14px; background: var(--bg); color: var(--text); border-bottom: 1px solid var(--line); }
.dot { width: 10px; height: 10px; border-radius: var(--r-round); flex-shrink: 0; }
.dot--a { background: var(--accent); }
.dot--t { background: var(--teal); }
.dot--p { background: var(--peri); }
.term-title { margin-left: 8px; font-family: var(--font-mono); font-size: var(--text-tiny); color: var(--muted); }
.term-note { margin-left: auto; font-size: var(--text-tiny); color: var(--muted); }
.term-body { display: block; padding: 12px 16px 14px; font-family: var(--font-mono); font-size: var(--text-tiny); line-height: 20px; color: var(--text); overflow-x: auto; }
.term-line { position: relative; display: block; padding-left: 16px; white-space: pre; animation: lineIn .45s ease-out both; }
.term-line::before { content: ""; position: absolute; left: 0; top: 7px; width: 6px; height: 6px; border-radius: var(--r-round); }
.ln-direct::before { background: var(--teal); }
.ln-block::before { background: var(--peri); }
.ln-proxy::before { background: var(--accent); }
.term-line:nth-child(2) { animation-delay: .12s; }
.term-line:nth-child(3) { animation-delay: .24s; }
.term-line:nth-child(4) { animation-delay: .36s; }
.term-line:nth-child(5) { animation-delay: .48s; }
.tk { color: var(--muted); }
.to-direct, .to-block, .to-proxy { color: var(--text); font-weight: var(--weight-strong); }
.caret { display: inline-block; width: 7px; height: 14px; margin-left: 4px; vertical-align: -2px; background: var(--accent); animation: blink 1.1s steps(1) 5; }
.sky-0 { stop-color: var(--sky-top); }
.sky-1 { stop-color: var(--sky-bottom); }
.f-cloud { fill: var(--cloud); }
.f-ridge { fill: var(--ridge); }
.f-m1 { fill: var(--peak-1); }
.f-m1s { fill: var(--peak-1-shade); }
.f-m2 { fill: var(--peak-2); }
.f-m2s { fill: var(--peak-2-shade); }
.f-snow { fill: var(--snow); }
.f-h1 { fill: var(--hill-1); }
.f-h2 { fill: var(--hill-2); }
.f-h3 { fill: var(--hill-3); }
.f-bush-a { fill: var(--bush-back); }
.f-bush-b { fill: var(--bush-front); }
.f-wave { fill: var(--bg); }
.s-river { fill: none; stroke: var(--river); stroke-linecap: round; stroke-linejoin: round; }
.s-river--thin { stroke-width: 6; }
.s-river--wide { stroke-width: 11; }
.s-branch { stroke-width: 9; }
.ripple { fill: none; stroke: var(--ripple); stroke-width: 2.4; stroke-linecap: round; animation: flowDown 3.9s linear infinite; }
.rp-right { animation-name: flowRight; }
.d1 { animation-delay: -1.3s; }
.d2 { animation-delay: -2.6s; }
.f-rock { fill: var(--rock); }
.f-post { fill: var(--post); }
.f-board { fill: var(--panel); }
.f-direct { fill: var(--teal); }
.f-proxy { fill: var(--accent); }
.f-block { fill: var(--panel); stroke: var(--peri); stroke-width: 2.5; }
.f-dot-light { fill: var(--panel); }
.s-dash { fill: none; stroke: var(--accent); stroke-width: 2; stroke-dasharray: 5 6; stroke-linecap: round; }
.s-arrow { fill: none; stroke: var(--accent); stroke-width: 2; stroke-linecap: round; stroke-linejoin: round; }
.t-mono, .t-cap { font-family: var(--font-mono); font-size: 12px; fill: var(--text); }
.t-cap { font-size: 12.5px; }
.t-node { font-family: var(--font-mono); font-size: 15px; font-weight: var(--weight-strong); fill: var(--text); }
.t-rock { font-family: var(--font-mono); font-size: 14px; font-weight: var(--weight-medium); fill: var(--text); }
.node { animation: nodeRise .9s ease-out both; }
.node--2 { animation-delay: .15s; }
.node--3 { animation-delay: .3s; }
.motion-toggle { position: absolute; width: 1px; height: 1px; opacity: 0; }
.pause-btn { position: absolute; right: 40px; bottom: 70px; z-index: 3; width: 44px; height: 44px; display: grid; place-items: center; border-radius: var(--r-round); border: 1.5px solid var(--text); background: var(--panel); color: var(--text); cursor: pointer; }
.pause-btn svg { width: 16px; height: 16px; }
.pause-btn .ic-play { display: none; }
.motion-toggle:checked ~ .pause-btn .ic-pause { display: none; }
.motion-toggle:checked ~ .pause-btn .ic-play { display: block; }
.motion-toggle:checked ~ .hero-visual *, .motion-toggle:checked ~ .hero-inner * { animation-play-state: paused; }
.motion-toggle:focus-visible ~ .pause-btn { outline: 2px solid var(--accent-dark); outline-offset: 3px; }
.peek { padding-top: 18px; padding-bottom: 96px; background: var(--bg); color: var(--text); text-align: center; }
.peek-eyebrow { display: inline-flex; align-items: center; gap: 10px; margin: 0; font-size: 13px; color: var(--muted); letter-spacing: .04em; }
.peek-eyebrow::before { content: ""; width: 18px; height: 2px; border-radius: var(--r-xs); background: var(--teal); }
.peek h2 { margin: 14px 0 0; font-size: var(--title-2); }
.peek p { margin: 14px auto 0; max-width: 36em; color: var(--muted); }
@keyframes flowDown { 0% { opacity: 0; transform: translate(0, -6px); } 25%, 75% { opacity: 1; } 100% { opacity: 0; transform: translate(-2px, 10px); } }
@keyframes flowRight { 0% { opacity: 0; transform: translate(-8px, 0); } 25%, 75% { opacity: 1; } 100% { opacity: 0; transform: translate(12px, 0); } }
@keyframes nodeRise { from { opacity: 0; transform: translateY(10px); } to { opacity: 1; transform: translateY(0); } }
@keyframes lineIn { from { opacity: 0; transform: translateY(4px); } to { opacity: 1; transform: translateY(0); } }
@keyframes blink { 0% { opacity: 1; } 50% { opacity: 0; } }
@media (max-width: 1120px) {
  .nav-dots { display: none; }
  .head-tools { margin-left: auto; }
  .menu-toggle { display: inline-flex; }
}
@media (min-width: 1121px) { .menu-drawer, .nav-veil { display: none !important; } }
@media (max-width: 1120px) {
  .site-head--hero { position: relative; background: var(--sky-top); color: var(--text); }
  .hero { height: auto; display: flex; flex-direction: column; background: var(--sky-top); color: var(--text); }
  .hero .hero-inner { order: 1; padding-top: 28px; padding-bottom: 8px; }
  .hero-copy { width: auto; max-width: 600px; }
  .term { width: 100%; }
  .hero-visual { position: relative; order: 2; width: 100%; aspect-ratio: 4 / 3; }
  .valley { width: 180%; height: 100%; left: -80%; }
  .pause-btn { right: 20px; bottom: 24px; }
  .footer-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (max-width: 768px) {
  :root { --gutter: 20px; --section-gap: 56px; --title-1: 28px; }
  .hero h1 { font-size: 28px; }
  .lead { font-size: 15.5px; }
  .card-grid { grid-template-columns: minmax(0, 1fr); }
  .platforms { gap: 12px 18px; }
  .term-note { display: none; }
  .term-body { font-size: 11px; line-height: 18px; }
  .term-line::before { top: 6px; }
  .btn { min-height: 46px; padding-inline: 20px; font-size: 15px; }
  .peek h2 { font-size: 24px; }
}
@media (max-width: 640px) {
  .tilt, [data-tilt] { transform: none !important; }
  .panel, .card { padding: 22px; }
  .head-row { gap: 10px; }
  .brand { font-size: 14px; gap: 7px; }
  .head-tools { gap: 8px; margin-left: auto; }
  .lang-full { display: none; }
  .lang-short { display: inline; }
  .lang { padding-inline: 10px; min-height: 44px; }
  .footer-grid { grid-template-columns: minmax(0, 1fr); }
  .hero-visual { aspect-ratio: 1 / 1; }
}
@media (max-width: 360px) {
  :root { --gutter: 16px; }
  .brand { font-size: 12px; }
  .brand-mark { width: 28px; height: 28px; }
  .head-tools { gap: 6px; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation: none !important; transition: none !important; }
  .reveal-ready .reveal:not(.shown) { opacity: 1; transform: none; }
  .ripple { opacity: .85; }
  .pause-btn { display: none; }
}