:root {
  --bg: #0c0c0d;
  --surface: #161618;
  --surface-strong: #202023;
  --text: #f2f0e9;
  --muted: #9b9a95;
  --line: rgba(242, 240, 233, 0.16);
  --accent: #ff6b35;
  --accent-soft: #ffb69b;
  --max: 1180px;
  color-scheme: dark;
}

:root[data-theme="light"] {
  --bg: #f3f0e8;
  --surface: #e7e2d7;
  --surface-strong: #ddd6c8;
  --text: #181818;
  --muted: #62605b;
  --line: rgba(24, 24, 24, 0.16);
  --accent: #e94f1d;
  --accent-soft: #943216;
  color-scheme: light;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: Inter, "PingFang SC", "Microsoft YaHei", system-ui, sans-serif;
  line-height: 1.6;
  transition: background .35s ease, color .35s ease;
}
a { color: inherit; text-decoration: none; }
button { font: inherit; }
::selection { background: var(--accent); color: #fff; }
.reading-progress { position: fixed; inset: 0 auto auto 0; z-index: 30; width: 0; height: 3px; background: var(--accent); }

.site-header {
  position: relative;
  z-index: 10;
  width: min(calc(100% - 48px), var(--max));
  height: 96px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  border-bottom: 1px solid var(--line);
}
.brand { justify-self: start; font-size: 24px; font-weight: 800; letter-spacing: -.08em; }
.brand span, footer > a span { color: var(--accent); }
nav { display: flex; gap: 32px; }
nav a { color: var(--muted); font-size: 12px; letter-spacing: .1em; transition: color .2s ease; }
nav a:hover, nav a:focus-visible { color: var(--text); }
.theme-toggle {
  justify-self: end;
  width: 38px;
  height: 38px;
  border: 1px solid var(--line);
  border-radius: 50%;
  background: transparent;
  color: var(--text);
  cursor: pointer;
}
.theme-toggle:hover, .theme-toggle:focus-visible { background: var(--surface); border-color: var(--accent); }

main { overflow: hidden; }
.section, .thesis {
  width: min(calc(100% - 48px), var(--max));
  margin: 0 auto;
  border-top: 1px solid var(--line);
}
.section { padding: 120px 0 130px; }
.section-kicker, .eyebrow {
  margin: 0;
  color: var(--muted);
  font: 700 11px/1.25 ui-monospace, SFMono-Regular, Menlo, monospace;
  letter-spacing: .2em;
  text-transform: uppercase;
}
.section-head { display: grid; grid-template-columns: .72fr 2fr 1.05fr; gap: 40px; align-items: start; margin-bottom: 76px; }
.section-head h2 { margin: -8px 0 0; font-size: clamp(40px, 5vw, 68px); line-height: 1.08; letter-spacing: -.055em; }
.section-intro { margin: 0; color: var(--muted); font-size: 15px; line-height: 1.9; }

.hero {
  width: min(calc(100% - 48px), var(--max));
  min-height: 790px;
  margin: 0 auto;
  padding: 100px 0 92px;
  display: grid;
  grid-template-columns: 1.32fr .68fr;
  gap: 76px;
  align-items: center;
}
.eyebrow { display: flex; align-items: center; gap: 12px; }
.eyebrow span { width: 7px; height: 7px; border-radius: 50%; background: var(--accent); box-shadow: 0 0 0 6px color-mix(in srgb, var(--accent) 14%, transparent); }
h1 { margin: 34px 0 0; font-size: clamp(62px, 7.2vw, 105px); line-height: .99; letter-spacing: -.075em; font-weight: 760; }
h1 em { color: var(--accent); font-family: Georgia, "Songti SC", serif; font-weight: 400; }
.hero-subtitle { margin: 32px 0 0; font-size: clamp(22px, 2.6vw, 34px); letter-spacing: -.03em; }
.hero-lead { max-width: 680px; margin: 32px 0 0; color: var(--muted); font-size: 16px; line-height: 1.95; }
.hero-shift { position: relative; min-height: 490px; padding: 34px; border: 1px solid var(--line); background: linear-gradient(145deg, var(--surface), color-mix(in srgb, var(--accent) 7%, var(--bg))); overflow: hidden; }
.hero-shift::before { content: ""; position: absolute; inset: 18px; border: 1px solid var(--line); pointer-events: none; }
.shift-label { position: relative; z-index: 2; color: var(--muted); font: 700 10px ui-monospace, monospace; letter-spacing: .18em; }
.shift-row { position: relative; z-index: 2; display: grid; grid-template-columns: 52px 1fr; gap: 8px 16px; }
.shift-row span { grid-row: 1 / 3; align-self: center; color: var(--accent); font: 700 10px ui-monospace, monospace; letter-spacing: .12em; }
.shift-row strong { font-size: 31px; line-height: 1; letter-spacing: -.04em; }
.shift-row small { color: var(--muted); font-size: 12px; }
.shift-row.old { margin-top: 56px; opacity: .58; }
.shift-row.new { margin-top: 24px; }
.shift-arrow { position: relative; z-index: 2; margin: 25px 0 0 66px; color: var(--accent); font-size: 22px; }
.shift-orbit { position: absolute; right: -55px; bottom: -58px; width: 250px; height: 250px; display: grid; place-items: center; }
.shift-orbit i { position: absolute; width: 210px; height: 112px; border: 1px solid color-mix(in srgb, var(--accent) 48%, transparent); border-radius: 50%; transform: rotate(24deg); }
.shift-orbit i:nth-child(2) { transform: rotate(-38deg); }
.shift-orbit b { width: 76px; height: 76px; display: grid; place-items: center; border-radius: 50%; background: var(--accent); color: #fff; font-size: 20px; }

.thesis { padding: 120px 0 132px; display: grid; grid-template-columns: .72fr 3fr; gap: 40px; }
.thesis > p:last-child { max-width: 980px; margin: -14px 0 0; font-size: clamp(36px, 4.9vw, 66px); line-height: 1.24; letter-spacing: -.055em; }
.thesis strong { color: var(--accent); font-family: Georgia, "Songti SC", serif; font-weight: 400; }

.path-compare { display: grid; grid-template-columns: 1fr 90px 1fr; align-items: stretch; }
.path { padding: 38px 40px 42px; border: 1px solid var(--line); background: var(--surface); }
.old-path { opacity: .68; }
.new-path { border-color: color-mix(in srgb, var(--accent) 55%, var(--line)); }
.path-title { display: flex; justify-content: space-between; align-items: center; margin-bottom: 48px; }
.path-title span { color: var(--accent); font: 700 10px ui-monospace, monospace; letter-spacing: .18em; }
.path-title h3 { margin: 0; font-size: 26px; }
.path ol { margin: 0; padding: 0; list-style: none; border-top: 1px solid var(--line); }
.path li { min-height: 68px; display: grid; grid-template-columns: 48px 1fr; align-items: center; border-bottom: 1px solid var(--line); }
.path li b { color: var(--accent); font: 700 10px ui-monospace, monospace; }
.path li span { font-size: 17px; font-weight: 650; }
.path > p { margin: 28px 0 0; color: var(--muted); font-size: 14px; line-height: 1.8; }
.user-intent { margin: -20px 0 26px; padding: 15px 17px; border-left: 3px solid var(--accent); background: color-mix(in srgb, var(--accent) 8%, transparent); font-size: 14px; line-height: 1.7; }
.path-switch { display: grid; place-content: center; gap: 13px; color: var(--muted); }
.path-switch span { writing-mode: vertical-rl; font: 700 9px ui-monospace, monospace; letter-spacing: .22em; }
.path-switch i { color: var(--accent); font-size: 24px; font-style: normal; }

.reason-grid { display: grid; grid-template-columns: repeat(6, 1fr); border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.reason-card { min-height: 320px; padding: 30px 25px 32px; border-right: 1px solid var(--line); }
.reason-card:nth-child(1), .reason-card:nth-child(2) { grid-column: span 3; min-height: 265px; border-bottom: 1px solid var(--line); }
.reason-card:nth-child(n+3) { grid-column: span 2; }
.reason-card:last-child, .reason-card:nth-child(2) { border-right: 0; }
.reason-card > span, .dna-card > span { color: var(--accent); font: 700 10px ui-monospace, monospace; letter-spacing: .12em; }
.reason-card h3 { margin: 66px 0 13px; font-size: 24px; }
.reason-card:nth-child(-n+2) h3 { margin-top: 50px; }
.reason-card p { margin: 0; color: var(--muted); font-size: 14px; line-height: 1.85; }

.case-list { border-top: 1px solid var(--line); }
.case { display: grid; grid-template-columns: 60px .72fr 1.15fr 1fr; gap: 28px; padding: 42px 0 45px; border-bottom: 1px solid var(--line); align-items: start; }
.case-index { color: var(--accent); font: 700 10px ui-monospace, monospace; }
.case-name span { color: var(--muted); font: 700 10px ui-monospace, monospace; letter-spacing: .12em; }
.case-name h3 { margin: 9px 0 0; font-size: 27px; letter-spacing: -.03em; }
.case-shift { display: grid; grid-template-columns: 42px 1fr; gap: 6px 8px; }
.case-shift small { color: var(--accent); font: 700 9px ui-monospace, monospace; letter-spacing: .1em; }
.case-shift p, .case-shift strong { margin: 0; }
.case-shift p { color: var(--muted); font-size: 13px; }
.case-shift i { grid-column: 2; color: var(--accent); font-style: normal; }
.case-shift strong { font-size: 15px; line-height: 1.65; }
.case-point b { font-size: 12px; }
.case-point p { margin: 8px 0 14px; color: var(--muted); font-size: 13px; line-height: 1.75; }
.case-point a { color: var(--accent); font-size: 11px; letter-spacing: .05em; border-bottom: 1px solid color-mix(in srgb, var(--accent) 35%, transparent); }

.dna-grid { display: grid; grid-template-columns: repeat(3, 1fr); border-top: 1px solid var(--line); }
.dna-card { min-height: 270px; padding: 30px 32px 34px; border-right: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.dna-card:nth-child(3n) { border-right: 0; }
.dna-card h3 { margin: 72px 0 12px; font-size: 23px; }
.dna-card p { margin: 0; color: var(--muted); font-size: 14px; line-height: 1.8; }

.compare-table { border-top: 1px solid var(--line); }
.compare-row { display: grid; grid-template-columns: .65fr 1fr 1fr; border-bottom: 1px solid var(--line); }
.compare-row > * { margin: 0; padding: 24px 28px; border-right: 1px solid var(--line); }
.compare-row > *:last-child { border-right: 0; }
.compare-row > span { color: var(--muted); font-size: 12px; }
.compare-row > p { font-size: 15px; }
.compare-row > p:last-child { color: var(--text); background: color-mix(in srgb, var(--accent) 7%, transparent); }
.compare-head { font: 700 10px ui-monospace, monospace; letter-spacing: .14em; }
.compare-head strong:last-child { color: var(--accent); }
.separate-note { max-width: 790px; margin: 42px 0 0 auto; padding-left: 28px; border-left: 3px solid var(--accent); font-size: 21px; line-height: 1.7; letter-spacing: -.015em; }

.question-list { margin: 0; padding: 0; list-style: none; border-top: 1px solid var(--line); }
.question-list li { display: grid; grid-template-columns: 100px 1fr; min-height: 150px; padding: 32px 0; border-bottom: 1px solid var(--line); align-items: center; }
.question-list > li > span { color: var(--accent); font: 700 11px ui-monospace, monospace; }
.question-list h3 { margin: 0; font-size: clamp(24px, 3vw, 38px); letter-spacing: -.035em; }
.question-list p { margin: 10px 0 0; color: var(--muted); font-size: 14px; }

.dual-line { display: grid; grid-template-columns: 1fr 58px 1fr 68px 1fr; align-items: center; }
.dual-line article { min-height: 300px; padding: 32px; border: 1px solid var(--line); background: var(--surface); }
.dual-line article > span { color: var(--accent); font: 700 10px ui-monospace, monospace; letter-spacing: .14em; }
.dual-line h3 { margin: 68px 0 14px; font-size: 26px; }
.dual-line p { margin: 0 0 28px; color: var(--muted); font-size: 14px; line-height: 1.8; }
.dual-line b { display: inline-block; padding: 6px 10px; color: var(--accent); border: 1px solid color-mix(in srgb, var(--accent) 35%, transparent); font-size: 11px; }
.dual-line .fulfill { background: color-mix(in srgb, var(--accent) 8%, var(--surface)); border-color: color-mix(in srgb, var(--accent) 55%, var(--line)); }
.plus, .equals { text-align: center; color: var(--accent); font-size: 26px; }
.vertical-note { max-width: 900px; margin: 52px auto 0; text-align: center; font-size: 21px; line-height: 1.8; letter-spacing: -.015em; }

.closing { padding-top: 132px; }
.closing > .section-kicker { margin-bottom: 76px; }
.closing-line { display: flex; justify-content: space-between; align-items: baseline; gap: 40px; padding: 25px 0; border-bottom: 1px solid var(--line); }
.closing-line span { color: var(--muted); font-size: 18px; }
.closing-line strong { color: var(--accent); font-family: Georgia, "Songti SC", serif; font-size: clamp(43px, 6.6vw, 86px); line-height: 1; font-weight: 400; letter-spacing: -.055em; }
.closing-final { max-width: 780px; margin: 92px 0 0 auto; font-size: clamp(31px, 4vw, 54px); line-height: 1.35; letter-spacing: -.045em; }

.sources { padding-bottom: 100px; display: grid; grid-template-columns: 1fr 2fr; gap: 68px; }
.sources-head > p:last-child { margin: 24px 0 0; color: var(--muted); font-size: 12px; line-height: 1.7; }
.sources ol { margin: 0; padding: 0; list-style: none; border-top: 1px solid var(--line); }
.sources li { border-bottom: 1px solid var(--line); }
.sources a { display: block; padding: 15px 4px; color: var(--muted); font-size: 12px; transition: color .2s ease, padding-left .2s ease; }
.sources a:hover, .sources a:focus-visible { color: var(--accent); padding-left: 10px; }

footer { width: min(calc(100% - 48px), var(--max)); margin: 0 auto; padding: 32px 0 42px; display: grid; grid-template-columns: 1fr 1fr 1fr auto; align-items: center; gap: 25px; border-top: 1px solid var(--line); color: var(--muted); font: 600 10px ui-monospace, monospace; letter-spacing: .15em; }
footer > a:first-child { color: var(--text); font-family: Inter, sans-serif; font-size: 20px; font-weight: 800; letter-spacing: -.08em; }
footer > a:last-child { width: 42px; height: 42px; display: grid; place-items: center; border: 1px solid var(--line); border-radius: 50%; color: var(--accent); font-size: 18px; }

.reveal { opacity: 1; transform: none; }
.js-ready .reveal { opacity: 0; transform: translateY(24px); transition: opacity .7s ease, transform .7s cubic-bezier(.2,.7,.2,1); }
.js-ready .reveal.is-visible { opacity: 1; transform: none; }

@media (max-width: 980px) {
  .section-head { grid-template-columns: .5fr 1.8fr; }
  .section-intro { grid-column: 2; }
  .hero { grid-template-columns: 1.1fr .9fr; gap: 38px; }
  .case { grid-template-columns: 45px .72fr 1.2fr; }
  .case-point { grid-column: 2 / -1; padding-left: calc(.72fr + 28px); }
  .dual-line { grid-template-columns: 1fr 42px 1fr; }
  .dual-line .equals { grid-column: 1 / -1; margin: 22px 0; transform: rotate(90deg); }
  .dual-line .fulfill { grid-column: 1 / -1; min-height: 230px; }
  .dual-line .fulfill h3 { margin-top: 45px; }
}

@media (max-width: 820px) {
  .site-header { width: min(calc(100% - 32px), var(--max)); height: 76px; grid-template-columns: 1fr auto; }
  nav { display: none; }
  .hero, .section, .thesis, footer { width: min(calc(100% - 32px), var(--max)); }
  .hero { min-height: 0; padding: 75px 0 85px; grid-template-columns: 1fr; gap: 60px; }
  h1 { font-size: clamp(53px, 15.5vw, 78px); }
  .hero-lead { font-size: 15px; }
  .hero-shift { min-height: 420px; }
  .section { padding: 88px 0 96px; }
  .thesis { padding: 86px 0 96px; grid-template-columns: 1fr; gap: 36px; }
  .thesis > p:last-child { margin: 0; font-size: clamp(35px, 10vw, 52px); }
  .section-head { grid-template-columns: 1fr; gap: 26px; margin-bottom: 50px; }
  .section-head h2 { margin: 0; font-size: clamp(38px, 11vw, 56px); }
  .section-intro { grid-column: auto; }
  .path-compare { grid-template-columns: 1fr; }
  .path-switch { min-height: 74px; grid-auto-flow: column; }
  .path-switch span { writing-mode: initial; }
  .path-switch i { transform: rotate(90deg); }
  .path { padding: 30px 24px 34px; }
  .reason-grid { grid-template-columns: 1fr; }
  .reason-card, .reason-card:nth-child(1), .reason-card:nth-child(2), .reason-card:nth-child(n+3) { grid-column: auto; min-height: 230px; border-right: 0; border-bottom: 1px solid var(--line); }
  .reason-card h3, .reason-card:nth-child(-n+2) h3 { margin-top: 45px; }
  .case { grid-template-columns: 38px 1fr; gap: 20px; }
  .case-shift, .case-point { grid-column: 2; padding-left: 0; }
  .dna-grid { grid-template-columns: 1fr; }
  .dna-card { min-height: 230px; padding: 28px 0; border-right: 0; }
  .dna-card h3 { margin-top: 48px; }
  .compare-row { grid-template-columns: .55fr 1fr 1fr; }
  .compare-row > * { padding: 18px 12px; font-size: 12px; }
  .separate-note { font-size: 18px; }
  .question-list li { grid-template-columns: 50px 1fr; min-height: 140px; }
  .dual-line { grid-template-columns: 1fr; }
  .dual-line .plus, .dual-line .equals { grid-column: auto; margin: 18px 0; transform: none; }
  .dual-line .fulfill { grid-column: auto; }
  .vertical-note { text-align: left; font-size: 18px; }
  .closing > .section-kicker { margin-bottom: 50px; }
  .closing-line { display: block; padding: 22px 0; }
  .closing-line span { display: block; margin-bottom: 8px; font-size: 14px; }
  .closing-line strong { display: block; font-size: clamp(42px, 13.5vw, 68px); }
  .closing-final { margin-top: 65px; }
  .sources { grid-template-columns: 1fr; gap: 38px; }
  footer { grid-template-columns: 1fr auto; }
  footer p { grid-column: 1; }
  footer > a:last-child { grid-column: 2; grid-row: 1 / 3; }
}

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