:root {
  color-scheme: dark;
  --bg: #071014;
  --bg-deep: #04090c;
  --panel: #0b181d;
  --panel-2: #0e2026;
  --line: rgba(133, 237, 225, .17);
  --line-strong: rgba(57, 230, 208, .45);
  --cyan: #39e6d0;
  --cyan-soft: #9af5e9;
  --violet: #7c66ff;
  --white: #eaf7f6;
  --muted: #9bb0b0;
  --warning: #ffcf70;
  --max: 1160px;
  --radius: 26px;
  --shadow: 0 28px 80px rgba(0, 0, 0, .32);
}

*, *::before, *::after { box-sizing: border-box; }

html {
  scroll-behavior: smooth;
  background: var(--bg-deep);
  overflow-x: hidden;
}

body {
  margin: 0;
  min-width: 320px;
  overflow-x: hidden;
  background:
    radial-gradient(circle at 15% 30%, rgba(57, 230, 208, .04), transparent 25%),
    radial-gradient(circle at 85% 70%, rgba(124, 102, 255, .05), transparent 24%),
    var(--bg);
  color: var(--white);
  font-family: -apple-system, BlinkMacSystemFont, "PingFang TC", "Noto Sans TC", "Microsoft JhengHei", sans-serif;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
}

a { color: inherit; }

button, a { -webkit-tap-highlight-color: transparent; }

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

:focus-visible {
  outline: 3px solid var(--cyan);
  outline-offset: 4px;
}

.skip-link {
  position: fixed;
  z-index: 200;
  top: 12px;
  left: 12px;
  transform: translateY(-160%);
  padding: 10px 16px;
  border-radius: 999px;
  background: var(--white);
  color: var(--bg);
  font-weight: 800;
  transition: transform .2s ease;
}

.skip-link:focus { transform: translateY(0); }

.scroll-progress {
  position: fixed;
  z-index: 120;
  top: 0;
  left: 0;
  width: 100%;
  height: 3px;
  background: rgba(255, 255, 255, .05);
}

.scroll-progress span {
  display: block;
  width: 0;
  height: 100%;
  background: linear-gradient(90deg, var(--cyan), var(--violet));
  box-shadow: 0 0 20px var(--cyan);
}

.hero {
  position: relative;
  min-height: 100svh;
  overflow: hidden;
  display: flex;
  flex-direction: column;
  isolation: isolate;
  background: #061014;
  border-bottom: 1px solid var(--line);
}

.hero-grid {
  position: absolute;
  inset: 0;
  z-index: -3;
  background-image:
    linear-gradient(rgba(57, 230, 208, .055) 1px, transparent 1px),
    linear-gradient(90deg, rgba(57, 230, 208, .055) 1px, transparent 1px);
  background-size: 58px 58px;
  mask-image: linear-gradient(to bottom, #000, transparent 92%);
}

.hero-grid::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(120deg, rgba(7, 16, 20, .12), rgba(7, 16, 20, .85) 80%);
}

.hero-glow {
  position: absolute;
  z-index: -2;
  border-radius: 50%;
  filter: blur(10px);
  opacity: .6;
  pointer-events: none;
}

.hero-glow-one {
  width: 560px;
  height: 560px;
  right: 2%;
  top: 15%;
  background: radial-gradient(circle, rgba(57, 230, 208, .13), transparent 68%);
}

.hero-glow-two {
  width: 420px;
  height: 420px;
  left: -180px;
  bottom: -180px;
  background: radial-gradient(circle, rgba(124, 102, 255, .16), transparent 70%);
}

.topbar {
  width: min(calc(100% - 48px), var(--max));
  margin: 0 auto;
  min-height: 96px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 24px;
  border-bottom: 1px solid var(--line);
}

.brand {
  display: inline-flex;
  gap: 12px;
  align-items: center;
  text-decoration: none;
}

.brand-mark, .footer-mark {
  width: 42px;
  height: 42px;
  display: grid;
  place-items: center;
  border: 1px solid var(--line-strong);
  border-radius: 12px;
  color: var(--cyan);
  font: 800 14px/1 ui-monospace, SFMono-Regular, Menlo, monospace;
  box-shadow: inset 0 0 20px rgba(57, 230, 208, .07);
}

.brand b, .brand small { display: block; }
.brand b { font-size: 14px; letter-spacing: .08em; }
.brand small { color: var(--muted); font-size: 11px; letter-spacing: .14em; }

.topbar-actions {
  display: flex;
  align-items: center;
  gap: 18px;
}

.language-switcher {
  display: inline-flex;
  padding: 3px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: rgba(7, 16, 20, .78);
}

.language-switcher button {
  min-height: 34px;
  padding: 7px 12px;
  border: 0;
  border-radius: 999px;
  background: transparent;
  color: var(--muted);
  font: 700 11px/1 -apple-system, BlinkMacSystemFont, "PingFang TC", "Noto Sans TC", sans-serif;
  cursor: pointer;
  transition: color .2s ease, background .2s ease, box-shadow .2s ease;
}

.language-switcher button:hover { color: var(--white); }

.language-switcher button[aria-pressed="true"] {
  background: rgba(57, 230, 208, .14);
  color: var(--cyan-soft);
  box-shadow: inset 0 0 0 1px rgba(57, 230, 208, .16);
}

.issue, .section-kicker, .panel-label, .lab-heading span, .closing-code > span {
  color: var(--cyan);
  font: 700 11px/1.4 ui-monospace, SFMono-Regular, Menlo, monospace;
  letter-spacing: .18em;
  text-transform: uppercase;
}

.hero-layout {
  width: min(calc(100% - 48px), var(--max));
  margin: auto;
  padding: 72px 0;
  display: grid;
  grid-template-columns: 1.1fr .9fr;
  gap: clamp(40px, 8vw, 110px);
  align-items: center;
}

.eyebrow {
  display: flex;
  gap: 10px;
  align-items: center;
  margin: 0 0 28px;
  color: var(--cyan-soft);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: .18em;
}

.eyebrow span {
  width: 30px;
  height: 1px;
  background: var(--cyan);
  box-shadow: 0 0 10px var(--cyan);
}

h1, h2, h3, p { margin-top: 0; }

h1 {
  margin-bottom: 30px;
  max-width: 760px;
  font-size: clamp(44px, 6vw, 82px);
  line-height: 1.04;
  letter-spacing: -.055em;
  font-weight: 800;
}

h1 em {
  color: transparent;
  font-style: normal;
  -webkit-text-stroke: 1.5px var(--cyan);
  text-shadow: 0 0 28px rgba(57, 230, 208, .18);
}

.lead {
  max-width: 650px;
  color: #bed0d0;
  font-size: clamp(17px, 2vw, 21px);
  line-height: 1.7;
}

.hero-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 1px;
  margin-top: 38px;
  border: 1px solid var(--line);
  background: var(--line);
  border-radius: 16px;
  overflow: hidden;
}

.hero-meta span {
  flex: 1 1 120px;
  padding: 14px 16px;
  background: rgba(7, 16, 20, .92);
  color: var(--muted);
  font-size: 11px;
}

.hero-meta b {
  display: block;
  color: var(--white);
  font: 700 13px/1.4 ui-monospace, SFMono-Regular, Menlo, monospace;
}

.system-orbit {
  position: relative;
  width: min(100%, 480px);
  aspect-ratio: 1;
  margin-inline: auto;
  display: grid;
  place-items: center;
}

.orbit {
  position: absolute;
  inset: 10%;
  border: 1px solid rgba(57, 230, 208, .32);
  border-radius: 50%;
  box-shadow: inset 0 0 45px rgba(57, 230, 208, .04), 0 0 40px rgba(57, 230, 208, .04);
}

.orbit-a { animation: spin 26s linear infinite; }
.orbit-a::before, .orbit-b::before {
  content: "";
  position: absolute;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--cyan);
  box-shadow: 0 0 20px 5px rgba(57, 230, 208, .45);
}
.orbit-a::before { left: 9%; top: 18%; }

.orbit-b {
  inset: 23%;
  border-color: rgba(124, 102, 255, .42);
  animation: spin 18s linear infinite reverse;
}
.orbit-b::before { right: 4%; bottom: 24%; background: var(--violet); box-shadow: 0 0 20px 5px rgba(124, 102, 255, .45); }

.orbit-core {
  position: relative;
  z-index: 2;
  width: 48%;
  aspect-ratio: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--line-strong);
  border-radius: 50%;
  background: radial-gradient(circle at 35% 30%, #14343a, #081317 70%);
  box-shadow: 0 0 70px rgba(57, 230, 208, .13), inset 0 0 40px rgba(57, 230, 208, .07);
}

.orbit-core span { color: var(--muted); font-size: 11px; letter-spacing: .15em; }
.orbit-core strong { font-size: clamp(18px, 2.6vw, 28px); line-height: 1.4; }
.orbit-core i { color: var(--cyan); font-style: normal; line-height: 1; }

.orbit-node {
  position: absolute;
  z-index: 3;
  min-width: 62px;
  padding: 8px 10px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: rgba(9, 25, 29, .9);
  color: var(--cyan-soft);
  text-align: center;
  font: 700 11px/1.2 ui-monospace, SFMono-Regular, Menlo, monospace;
  box-shadow: 0 10px 30px rgba(0, 0, 0, .25);
}
.node-one { left: 2%; top: 42%; }
.node-two { right: 5%; top: 18%; }
.node-three { right: 0; bottom: 26%; }
.node-four { left: 22%; bottom: 2%; }

.hero-bottom {
  width: min(calc(100% - 48px), var(--max));
  margin: 0 auto;
  padding: 22px 0 28px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 24px;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 12px;
}
.hero-bottom p { margin: 0; }
.hero-bottom p span { color: var(--warning); }
.hero-bottom a { color: var(--white); text-decoration: none; font-weight: 700; }
.hero-bottom a span { margin-left: 8px; color: var(--cyan); }

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 10px;
}

.hero-actions a {
  min-height: 40px;
  padding: 8px 13px;
  display: inline-flex;
  align-items: center;
  border-radius: 999px;
}

.hero-actions .download-link {
  border: 1px solid var(--line-strong);
  background: rgba(57, 230, 208, .09);
  color: var(--cyan-soft);
}

.hero-actions .download-link:hover { background: rgba(57, 230, 208, .16); }

.chapter-nav {
  position: sticky;
  z-index: 100;
  top: 3px;
  display: flex;
  justify-content: center;
  gap: 4px;
  padding: 10px 18px;
  overflow-x: auto;
  background: rgba(4, 9, 12, .88);
  border-bottom: 1px solid var(--line);
  backdrop-filter: blur(18px);
  scrollbar-width: none;
}
.chapter-nav::-webkit-scrollbar { display: none; }
.chapter-nav a {
  flex: 0 0 auto;
  padding: 9px 14px;
  border-radius: 999px;
  color: var(--muted);
  text-decoration: none;
  font-size: 12px;
  transition: color .2s ease, background .2s ease;
}
.chapter-nav a span { margin-right: 6px; color: var(--cyan); font-family: ui-monospace, monospace; }
.chapter-nav a:hover, .chapter-nav a.is-active { color: var(--white); background: rgba(57, 230, 208, .1); }

main { width: min(calc(100% - 48px), var(--max)); margin: 0 auto; }

.source-note {
  max-width: 880px;
  margin: 70px auto 0;
  padding: 20px 24px;
  display: flex;
  gap: 16px;
  align-items: flex-start;
  border: 1px solid rgba(255, 207, 112, .25);
  border-radius: 18px;
  background: rgba(255, 207, 112, .045);
  color: #d6d4c6;
}
.source-note p { margin: 0; font-size: 13px; }
.source-note b { color: var(--warning); margin-right: 8px; }
.note-icon {
  flex: 0 0 28px;
  height: 28px;
  display: grid;
  place-items: center;
  border: 1px solid rgba(255, 207, 112, .45);
  border-radius: 50%;
  color: var(--warning);
  font: 800 13px/1 ui-monospace, monospace;
}

.section { padding: 130px 0; scroll-margin-top: 72px; }
.section + .section { border-top: 1px solid var(--line); }

.section-heading { max-width: 800px; margin-bottom: 62px; }
.section-index { margin-bottom: 18px; color: var(--muted); font: 600 12px/1 ui-monospace, monospace; }
.section-kicker { margin-bottom: 16px; }
.section-heading h2, .verification h2 {
  margin-bottom: 22px;
  font-size: clamp(34px, 5vw, 60px);
  line-height: 1.12;
  letter-spacing: -.04em;
}
.section-heading > p:last-child { max-width: 700px; color: var(--muted); font-size: 18px; }

.shift-grid {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  gap: 24px;
  align-items: center;
}

.shift-card {
  min-height: 310px;
  padding: 34px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: linear-gradient(145deg, rgba(16, 37, 43, .92), rgba(8, 19, 23, .92));
  box-shadow: var(--shadow);
}
.shift-card.new-way { border-color: rgba(57, 230, 208, .34); background: linear-gradient(145deg, rgba(21, 57, 61, .9), rgba(8, 22, 26, .95)); }
.card-tag {
  display: inline-block;
  margin-bottom: 40px;
  padding: 6px 10px;
  border: 1px solid var(--line);
  border-radius: 999px;
  color: var(--muted);
  font-size: 11px;
}
.new-way .card-tag { color: var(--cyan-soft); border-color: var(--line-strong); }
.shift-card h3 { font-size: 25px; }
.shift-card ul { margin: 0; padding: 0; list-style: none; color: var(--muted); }
.shift-card li { position: relative; padding: 9px 0 9px 22px; border-bottom: 1px solid rgba(255, 255, 255, .05); }
.shift-card li::before { content: "·"; position: absolute; left: 4px; color: var(--cyan); }
.shift-arrow { color: var(--cyan); font: 700 30px/1 ui-monospace, monospace; }
.shift-arrow span { display: block; margin-bottom: 8px; color: var(--muted); font-size: 9px; letter-spacing: .18em; writing-mode: vertical-rl; }

.core-quote {
  position: relative;
  margin: 90px auto;
  padding: 52px 9%;
  border-left: 2px solid var(--cyan);
  background: linear-gradient(90deg, rgba(57, 230, 208, .1), transparent 80%);
}
.core-quote span { color: var(--cyan); font: 700 11px/1 ui-monospace, monospace; letter-spacing: .16em; }
.core-quote p { margin: 18px 0 0; max-width: 850px; font-size: clamp(25px, 3.8vw, 43px); line-height: 1.45; font-weight: 700; letter-spacing: -.025em; }

.capability-lab {
  padding: clamp(28px, 5vw, 56px);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background:
    linear-gradient(rgba(57, 230, 208, .03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(57, 230, 208, .03) 1px, transparent 1px),
    rgba(6, 16, 20, .75);
  background-size: 32px 32px;
}
.lab-heading { margin-bottom: 42px; }
.lab-heading h3 { margin: 12px 0 0; font-size: clamp(22px, 3vw, 34px); }
.pipeline { display: grid; grid-template-columns: repeat(9, auto); gap: 12px; align-items: center; }
.pipeline article {
  min-width: 0;
  min-height: 152px;
  padding: 20px 14px;
  display: flex;
  flex-direction: column;
  justify-content: center;
  border: 1px solid var(--line);
  border-radius: 16px;
  background: rgba(11, 31, 35, .9);
  text-align: center;
}
.pipeline article b { color: var(--cyan); font: 700 11px/1 ui-monospace, monospace; }
.pipeline article strong { margin: 12px 0 5px; font-size: 18px; }
.pipeline article small { color: var(--muted); font-size: 11px; line-height: 1.5; }
.pipeline-link { color: var(--cyan); font-family: ui-monospace, monospace; }
.pipeline .loop-node { border-color: rgba(124, 102, 255, .5); box-shadow: inset 0 0 28px rgba(124, 102, 255, .08); }
.pipeline .loop-node b { color: #aa9dff; font-size: 18px; }

.three-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.concept-card {
  position: relative;
  overflow: hidden;
  min-height: 360px;
  padding: 30px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: linear-gradient(155deg, rgba(16, 40, 46, .9), rgba(7, 17, 21, .96));
}
.concept-card::after {
  content: "";
  position: absolute;
  width: 170px;
  height: 170px;
  right: -80px;
  top: -80px;
  border-radius: 50%;
  background: rgba(57, 230, 208, .07);
  filter: blur(2px);
}
.concept-number { color: var(--muted); font: 700 11px/1 ui-monospace, monospace; }
.concept-icon {
  width: 72px;
  height: 72px;
  margin: 44px 0 34px;
  display: grid;
  place-items: center;
  border: 1px solid var(--line-strong);
  border-radius: 20px;
  color: var(--cyan);
  font-size: 27px;
  box-shadow: inset 0 0 24px rgba(57, 230, 208, .08);
}
.concept-card h3 { font-size: 28px; }
.concept-card p { color: #becdcd; }
.concept-card small { color: var(--cyan-soft); font-size: 11px; }

.scenario-panel {
  margin-top: 24px;
  padding: clamp(28px, 5vw, 54px);
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 64px;
  border: 1px solid rgba(124, 102, 255, .35);
  border-radius: var(--radius);
  background: linear-gradient(135deg, rgba(124, 102, 255, .1), rgba(8, 20, 25, .95) 58%);
}
.scenario-panel h3 { margin-top: 16px; font-size: clamp(24px, 3vw, 34px); }
.scenario-panel > div > p:last-child { color: var(--muted); }
.journey { margin: 0; padding: 0; list-style: none; counter-reset: none; }
.journey li { display: flex; gap: 16px; align-items: center; padding: 14px 0; border-bottom: 1px solid var(--line); color: #c8d6d6; }
.journey li span { color: var(--cyan); font: 700 11px/1 ui-monospace, monospace; }
.short-drama {
  margin-top: 24px;
  padding: 28px 34px;
  display: grid;
  grid-template-columns: auto .7fr 1.3fr;
  gap: 28px;
  align-items: center;
  border: 1px solid var(--line);
  border-radius: 20px;
  background: var(--panel);
}
.short-drama p { margin-bottom: 0; color: var(--muted); }
.short-drama h3 { margin: 8px 0 0; }
.signal { width: 12px; height: 12px; border-radius: 50%; background: var(--cyan); box-shadow: 0 0 22px 6px rgba(57, 230, 208, .35); }

.path-list { display: grid; gap: 14px; }
.path-card {
  padding: 24px 28px;
  display: grid;
  grid-template-columns: 105px 1fr auto;
  gap: 28px;
  align-items: center;
  border: 1px solid var(--line);
  border-radius: 20px;
  background: rgba(11, 28, 33, .72);
  transition: transform .25s ease, border-color .25s ease;
}
.path-card:hover { transform: translateY(-3px); border-color: var(--line-strong); }
.path-id { color: var(--cyan); font: 700 11px/1 ui-monospace, monospace; letter-spacing: .12em; }
.path-content h3 { margin-bottom: 6px; font-size: 23px; }
.path-content p { margin: 0; color: var(--muted); }
.path-key { padding: 7px 12px; border: 1px solid var(--line); border-radius: 999px; color: var(--cyan-soft); font-size: 11px; white-space: nowrap; }
.boundary-note { margin: 34px 0 0; padding: 20px 24px; border-left: 2px solid var(--warning); background: rgba(255, 207, 112, .04); color: var(--muted); }
.boundary-note b { margin-right: 12px; color: var(--warning); }

.agent-layout { display: grid; grid-template-columns: 1.05fr .95fr; gap: 48px; align-items: center; }
.agent-stack { display: grid; gap: 10px; }
.agent-stack article {
  padding: 18px 20px;
  display: grid;
  grid-template-columns: 42px 1fr auto;
  gap: 14px;
  align-items: center;
  border: 1px solid var(--line);
  border-radius: 16px;
  background: var(--panel);
}
.agent-stack article > span { color: var(--cyan); font: 700 11px/1 ui-monospace, monospace; }
.agent-stack h3 { margin: 0 0 3px; font-size: 17px; }
.agent-stack p { margin: 0; color: var(--muted); font-size: 13px; }
.agent-stack article > b { color: #73908f; font: 700 9px/1 ui-monospace, monospace; letter-spacing: .08em; }
.agent-stack > small { padding: 7px 4px 0; color: var(--warning); font-size: 11px; }

.execution-loop {
  position: relative;
  min-height: 550px;
  display: grid;
  place-items: center;
}
.execution-loop::before, .execution-loop::after {
  content: "";
  position: absolute;
  inset: 17%;
  border: 1px dashed rgba(57, 230, 208, .27);
  border-radius: 50%;
}
.execution-loop::after { inset: 28%; border-style: solid; border-color: rgba(124, 102, 255, .28); }
.loop-center {
  position: relative;
  z-index: 2;
  width: 145px;
  height: 145px;
  display: grid;
  place-content: center;
  border: 1px solid var(--line-strong);
  border-radius: 50%;
  background: radial-gradient(circle, #15383d, #071115 70%);
  text-align: center;
  box-shadow: 0 0 65px rgba(57, 230, 208, .14);
}
.loop-center span { color: var(--cyan); font: 700 11px/1.5 ui-monospace, monospace; letter-spacing: .14em; }
.loop-center strong { font-size: 20px; }
.loop-step {
  position: absolute;
  z-index: 3;
  min-width: 112px;
  padding: 11px 14px;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: rgba(9, 25, 29, .95);
  color: #ccdada;
  font-size: 12px;
  box-shadow: 0 14px 35px rgba(0, 0, 0, .25);
}
.loop-step span { display: block; margin-bottom: 2px; color: var(--cyan); font: 700 9px/1 ui-monospace, monospace; }
.step-a { top: 3%; left: 50%; transform: translateX(-50%); }
.step-b { top: 24%; right: 1%; }
.step-c { bottom: 18%; right: 3%; }
.step-d { bottom: 4%; left: 50%; transform: translateX(-50%); }
.step-e { bottom: 18%; left: 3%; }
.step-f { top: 24%; left: 1%; }

.agent-compare {
  margin-top: 54px;
  padding: 34px;
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  gap: 30px;
  align-items: center;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: linear-gradient(110deg, rgba(57, 230, 208, .06), rgba(124, 102, 255, .06));
}
.agent-compare article > span { color: var(--cyan); font-size: 11px; letter-spacing: .12em; }
.agent-compare h3 { margin: 10px 0 8px; font-size: 24px; }
.agent-compare p { margin: 0; color: var(--muted); }
.agent-compare > div { color: var(--violet); font-size: 34px; }

.action-steps { margin: 0; padding: 0; list-style: none; display: grid; grid-template-columns: repeat(2, 1fr); gap: 1px; border: 1px solid var(--line); border-radius: var(--radius); overflow: hidden; background: var(--line); }
.action-steps li { min-height: 142px; padding: 28px; display: grid; grid-template-columns: 52px 1fr; gap: 14px; background: var(--panel); }
.action-steps li:last-child { grid-column: 1 / -1; }
.action-steps li > span { width: 40px; height: 40px; display: grid; place-items: center; border: 1px solid var(--line-strong); border-radius: 12px; color: var(--cyan); font: 700 11px/1 ui-monospace, monospace; }
.action-steps h3 { margin-bottom: 5px; font-size: 20px; }
.action-steps p { margin: 0; color: var(--muted); font-size: 14px; }
.closing-code { margin-top: 50px; padding: clamp(34px, 6vw, 70px); border: 1px solid rgba(124, 102, 255, .35); border-radius: var(--radius); background: radial-gradient(circle at 80% 20%, rgba(124, 102, 255, .17), transparent 42%), var(--panel); }
.closing-code p { margin: 18px 0 0; font-size: clamp(27px, 4vw, 48px); line-height: 1.4; font-weight: 750; letter-spacing: -.025em; }

.verification {
  margin: 0 0 110px;
  padding: clamp(30px, 5vw, 54px);
  display: grid;
  grid-template-columns: .7fr 1.3fr;
  gap: 64px;
  border: 1px solid rgba(255, 207, 112, .22);
  border-radius: var(--radius);
  background: rgba(255, 207, 112, .035);
}
.verification h2 { margin-bottom: 0; font-size: clamp(28px, 4vw, 42px); }
.verification ul { margin: 0; padding-left: 20px; color: #c6c8bd; }
.verification li { padding: 7px 0; }
.verification li::marker { color: var(--warning); }

.footer {
  padding: 44px max(24px, calc((100vw - var(--max)) / 2));
  display: flex;
  justify-content: space-between;
  gap: 36px;
  align-items: center;
  border-top: 1px solid var(--line);
  background: var(--bg-deep);
  color: var(--muted);
  font-size: 12px;
}
.footer > div { display: flex; gap: 16px; align-items: center; }
.footer p { margin: 0; }
.footer b { color: var(--white); }
.footer > p { text-align: right; }

.back-top {
  position: fixed;
  z-index: 110;
  right: 22px;
  bottom: 22px;
  width: 48px;
  height: 48px;
  border: 1px solid var(--line-strong);
  border-radius: 15px;
  background: rgba(8, 27, 31, .92);
  color: var(--cyan);
  font-size: 20px;
  cursor: pointer;
  opacity: 0;
  pointer-events: none;
  transform: translateY(12px);
  transition: opacity .2s ease, transform .2s ease;
  backdrop-filter: blur(12px);
}
.back-top.is-visible { opacity: 1; pointer-events: auto; transform: translateY(0); }

.reveal { opacity: 1; transform: none; }
.js .reveal { opacity: 0; transform: translateY(22px); transition: opacity .7s ease, transform .7s ease; }
.js .reveal.is-visible { opacity: 1; transform: none; }

@keyframes spin { to { transform: rotate(360deg); } }

@media (max-width: 920px) {
  .hero-layout { grid-template-columns: 1fr; padding-top: 54px; }
  .hero-copy { max-width: 760px; }
  .system-orbit { width: min(88vw, 430px); }
  .pipeline { grid-template-columns: 1fr; }
  .pipeline-link { transform: rotate(90deg); text-align: center; }
  .pipeline article { min-height: 112px; }
  .three-grid { grid-template-columns: 1fr; }
  .concept-card { min-height: 0; }
  .concept-icon { margin: 30px 0 24px; }
  .agent-layout { grid-template-columns: 1fr; }
  .execution-loop { width: min(100%, 560px); margin: 0 auto; }
}

@media (max-width: 720px) {
  .topbar, .hero-layout, .hero-bottom, main { width: min(calc(100% - 32px), var(--max)); }
  .topbar { min-height: 78px; }
  .issue { display: none; }
  .topbar-actions { gap: 0; }
  .hero { min-height: auto; }
  .hero-layout { padding: 58px 0 42px; gap: 38px; }
  h1 { font-size: clamp(39px, 13vw, 60px); }
  .lead { font-size: 16px; }
  .hero-meta span { min-width: 30%; }
  .system-orbit { width: min(92vw, 380px); }
  .orbit-node { min-width: 56px; font-size: 10px; }
  .hero-bottom { align-items: flex-start; }
  .hero-bottom p { max-width: 58%; }
  .hero-actions { max-width: 42%; justify-content: flex-end; }
  .chapter-nav { justify-content: flex-start; padding-inline: 12px; }
  .source-note { margin-top: 44px; padding: 16px; }
  .section { padding: 92px 0; }
  .section-heading { margin-bottom: 42px; }
  .section-heading > p:last-child { font-size: 16px; }
  .shift-grid { grid-template-columns: 1fr; }
  .shift-arrow { transform: rotate(90deg); justify-self: center; }
  .shift-arrow span { display: none; }
  .shift-card { min-height: 0; }
  .core-quote { margin: 62px 0; padding: 38px 24px; }
  .capability-lab { padding: 24px 18px; }
  .scenario-panel { grid-template-columns: 1fr; gap: 28px; }
  .short-drama { grid-template-columns: auto 1fr; }
  .short-drama > p { grid-column: 1 / -1; }
  .path-card { grid-template-columns: 1fr; gap: 12px; }
  .path-key { justify-self: start; }
  .agent-stack article { grid-template-columns: 34px 1fr; }
  .agent-stack article > b { grid-column: 2; }
  .execution-loop { min-height: 450px; }
  .loop-step { min-width: 102px; padding: 9px 10px; }
  .step-b { right: -5px; }
  .step-c { right: 0; }
  .step-e { left: 0; }
  .step-f { left: -5px; }
  .agent-compare { grid-template-columns: 1fr; }
  .agent-compare > div { transform: rotate(90deg); justify-self: center; line-height: 1; }
  .action-steps { grid-template-columns: 1fr; }
  .action-steps li:last-child { grid-column: auto; }
  .verification { grid-template-columns: 1fr; gap: 26px; }
  .footer { flex-direction: column; align-items: flex-start; }
  .footer > p { text-align: left; }
}

@media (max-width: 420px) {
  .brand { gap: 9px; }
  .brand-mark { width: 38px; height: 38px; }
  .brand b { font-size: 12px; letter-spacing: .04em; }
  .brand small { font-size: 9px; letter-spacing: .08em; }
  .language-switcher button { min-height: 32px; padding: 7px 8px; font-size: 10px; }
  .hero-bottom { flex-direction: column; }
  .hero-bottom p, .hero-actions { max-width: none; width: 100%; }
  .hero-actions { justify-content: flex-start; }
  .hero-meta { display: grid; grid-template-columns: repeat(3, 1fr); }
  .hero-meta span { padding: 11px 9px; }
  .hero-meta b { font-size: 11px; }
  .system-orbit { width: 330px; max-width: 100%; }
  .orbit-core { width: 52%; }
  .orbit-core strong { font-size: 17px; }
  .short-drama { padding: 24px 20px; }
  .execution-loop { min-height: 420px; transform: scale(.96); }
  .loop-center { width: 124px; height: 124px; }
  .loop-step { min-width: 94px; font-size: 11px; }
  .closing-code { padding: 30px 24px; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation-duration: .01ms !important; animation-iteration-count: 1 !important; transition-duration: .01ms !important; }
  .js .reveal { opacity: 1; transform: none; }
}