:root {
  --ink: #1d1f1c;
  --paper: #f2efe5;
  --cream: #fffdf7;
  --acid: #d8ff3e;
  --orange: #ff6338;
  --blue: #225f8d;
  --line: rgba(29, 31, 28, 0.18);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  color: var(--ink);
  background:
    radial-gradient(circle at 16% 8%, rgba(216, 255, 62, .2), transparent 21%),
    linear-gradient(135deg, rgba(255,255,255,.55), transparent 42%), var(--paper);
  font-family: Arial, "PingFang SC", "Microsoft YaHei", sans-serif;
}
button, input { font: inherit; }
button { color: inherit; }
a { color: inherit; text-decoration: none; }
p { text-wrap: pretty; }
button:focus-visible, a:focus-visible, summary:focus-visible {
  outline: 3px solid var(--orange);
  outline-offset: 4px;
}

.nav-shell {
  width: min(1400px, calc(100% - 56px));
  margin: 0 auto;
  height: 84px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-bottom: 1px solid var(--line);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: .08em;
}
.brand { display: flex; align-items: center; gap: 12px; }
.brand-mark {
  display: grid; place-items: center;
  width: 34px; height: 34px;
  background: var(--ink); color: var(--paper);
  font-size: 15px; letter-spacing: 0;
}
.nav-links { display: flex; gap: 30px; color: #5b5e57; }
.nav-links a { transition: color .2s ease; }
.nav-links a:hover { color: var(--orange); }
.nav-meta { display: flex; align-items: center; gap: 9px; color: #686b63; }
.status-dot { display: inline-block; flex: 0 0 auto; width: 8px; height: 8px; border-radius: 50%; background: var(--acid); box-shadow: 0 0 0 4px rgba(216,255,62,.22); }

.hero {
  width: min(1400px, calc(100% - 56px));
  min-height: 760px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1.05fr .95fr;
  align-items: center;
  gap: 70px;
  padding: 72px 0 86px;
}
.eyebrow { margin: 0 0 24px; font-size: 12px; font-weight: 800; letter-spacing: .18em; }
h1 { margin: 0; font-size: clamp(64px, 7.2vw, 118px); line-height: .94; letter-spacing: -.08em; font-weight: 900; }
h1 span { color: var(--orange); }
.hero-lead { max-width: 650px; margin: 34px 0; font-size: 18px; line-height: 1.8; color: #55594f; }
.hero-actions { display: flex; gap: 12px; flex-wrap: wrap; }
.button { padding: 17px 22px; border: 1px solid var(--ink); font-size: 14px; font-weight: 700; transition: .2s ease; }
.button:hover { transform: translateY(-2px); box-shadow: 5px 5px 0 var(--ink); }
.button-primary { background: var(--ink); color: white; }
.button-quiet { background: rgba(255,255,255,.32); }
.hero-stats { display: flex; gap: 0; margin: 58px 0 0; }
.hero-stats div { min-width: 142px; padding: 0 22px; border-left: 1px solid var(--line); }
.hero-stats div:first-child { padding-left: 0; border-left: 0; }
.hero-stats dt { font-size: 20px; font-weight: 900; letter-spacing: -.04em; }
.hero-stats dd { margin: 7px 0 0; font-size: 12px; color: #6b6e66; }

.hero-stage { position: relative; min-height: 620px; display: grid; place-items: center; }
.hero-stage::before {
  content: ""; position: absolute; inset: 35px 6% 30px 15%;
  border: 1px solid var(--ink); transform: rotate(4deg); background: var(--acid);
}
.poster-card {
  position: relative; z-index: 1; width: 390px; aspect-ratio: 3 / 4;
  overflow: hidden; background: linear-gradient(165deg, #f9d49b, #ffd2ad 43%, #d9eecc);
  border: 1px solid var(--ink); box-shadow: 14px 16px 0 rgba(29,31,28,.9);
}
.poster-scene { position: absolute; width: 260px; height: 260px; border-radius: 50%; top: 92px; right: -50px; background: radial-gradient(circle at 40% 40%, #fff9c7, #ff8455 70%); }
.poster-card::after { content: ""; position: absolute; width: 430px; height: 210px; background: #66906f; border-radius: 50% 50% 0 0; bottom: -80px; left: -80px; transform: rotate(-8deg); }
.poster-label { position: absolute; top: 25px; left: 25px; border-top: 2px solid; padding-top: 7px; font-size: 10px; letter-spacing: .2em; }
.poster-copy { position: absolute; z-index: 2; left: 28px; top: 175px; font-size: 28px; line-height: 1.32; letter-spacing: -.04em; }
.poster-copy strong { font-size: 44px; font-weight: 900; }
.poster-date { position: absolute; z-index: 3; left: 28px; bottom: 25px; display: flex; align-items: flex-end; gap: 10px; color: #fffdf7; }
.poster-date b { font-size: 92px; line-height: .75; letter-spacing: -.08em; }
.poster-date span { font-size: 11px; line-height: 1.1; font-weight: 800; letter-spacing: .08em; }
.poster-line { position: absolute; z-index: 3; right: 22px; bottom: 29px; height: 54px; border-left: 1px solid white; }
.stage-note { position: absolute; z-index: 2; padding: 9px 12px; border: 1px solid var(--ink); background: var(--cream); font-size: 10px; font-weight: 800; letter-spacing: .12em; }
.note-top { right: 1%; top: 65px; transform: rotate(3deg); }
.note-bottom { left: 2%; bottom: 62px; transform: rotate(-5deg); background: var(--orange); color: white; }

.trust-strip { min-height: 76px; padding: 0 max(28px, calc((100vw - 1400px) / 2)); background: var(--acid); display: flex; align-items: center; justify-content: center; gap: 24px; border-block: 1px solid var(--ink); font-size: 12px; font-weight: 800; letter-spacing: .06em; }
.trust-strip > span { padding: 10px 13px; background: var(--ink); color: white; }
.trust-strip p { margin: 0; }
.trust-strip i { font-style: normal; color: rgba(29,31,28,.35); }

.section-heading { width: min(1400px, calc(100% - 56px)); margin: 0 auto 60px; display: grid; grid-template-columns: 1fr .42fr; gap: 70px; align-items: end; }
.section-heading h2, .workflow-title h2, .standard-intro h2, .stack-copy h2, .status-section h2, .details-section > h2 { margin: 0; font-size: clamp(42px, 4.8vw, 76px); line-height: 1.06; letter-spacing: -.065em; }
.section-heading > p { margin: 0; color: #62655f; font-size: 15px; line-height: 1.8; }

.experience-section { padding: 120px 0 130px; color: var(--cream); background: var(--ink); }
.section-heading.light > p { color: #b5b8b1; }
.demo-layout { width: min(1400px, calc(100% - 56px)); margin: 0 auto; display: grid; grid-template-columns: .65fr 1.05fr .72fr; gap: 22px; align-items: stretch; }
.scenario-picker { display: flex; flex-direction: column; gap: 8px; }
.scenario-picker button { width: 100%; padding: 20px; border: 1px solid rgba(255,255,255,.16); background: rgba(255,255,255,.035); color: white; text-align: left; cursor: pointer; display: grid; grid-template-columns: 34px 1fr; gap: 5px 9px; transition: .2s ease; }
.scenario-picker button:hover, .scenario-picker button.selected { border-color: var(--acid); background: rgba(216,255,62,.1); }
.scenario-picker button.selected { box-shadow: inset 3px 0 var(--acid); }
.scenario-picker button span { grid-row: 1 / 3; color: var(--acid); font-size: 11px; font-weight: 800; }
.scenario-picker button b { font-size: 15px; }
.scenario-picker button small { font-size: 12px; line-height: 1.5; color: #aeb1aa; }

.demo-console { min-height: 560px; border: 1px solid rgba(255,255,255,.25); background: #282b27; padding: 20px; display: flex; flex-direction: column; box-shadow: 10px 10px 0 var(--orange); }
.demo-topbar { display: flex; justify-content: space-between; border-bottom: 1px solid rgba(255,255,255,.18); padding-bottom: 18px; font-weight: 700; }
.demo-topbar span { display: flex; gap: 9px; align-items: center; }
.demo-topbar i { width: 8px; height: 8px; background: var(--acid); border-radius: 50%; }
.demo-topbar small { color: #adb0a9; letter-spacing: .12em; }
.chat-area { flex: 1; display: flex; flex-direction: column; min-height: 0; }
.message { max-width: 82%; margin: 26px 0 20px auto; padding: 14px 17px; background: var(--cream); color: var(--ink); border-radius: 16px 16px 2px 16px; font-size: 13px; line-height: 1.55; }
.idle-state { margin: auto; text-align: center; color: #aeb1aa; }
.idle-state::before { content: "↗"; display: grid; place-items: center; width: 48px; height: 48px; margin: 0 auto 14px; border: 1px solid rgba(255,255,255,.2); border-radius: 50%; color: var(--acid); font-size: 22px; }
.idle-state p { margin: 0 0 7px; color: white; font-weight: 700; }
.idle-state span { font-size: 12px; }
.step-list { display: grid; gap: 5px; margin: 0 0 16px; }
.step-list > div { display: grid; grid-template-columns: 24px 1fr auto; align-items: center; padding: 8px 10px; border-left: 2px solid rgba(255,255,255,.12); background: rgba(255,255,255,.025); color: #777b74; transition: .25s ease; }
.step-list > div.active { color: white; border-left-color: var(--acid); background: rgba(216,255,62,.08); }
.step-list > div.complete { color: #bfc2bb; }
.step-list > div span { font-size: 10px; }
.step-list > div.complete span { color: var(--acid); }
.step-list p { margin: 0; font-size: 12px; font-weight: 700; }
.step-list small { font-size: 9px; letter-spacing: .06em; }
.result-message { margin-top: auto; padding: 13px; background: rgba(216,255,62,.1); border: 1px solid rgba(216,255,62,.3); }
.result-message span { font-size: 11px; font-weight: 800; color: var(--acid); }
.result-message p { margin: 5px 0 0; font-size: 10px; line-height: 1.5; color: #bec1ba; }
.run-button { width: 100%; min-height: 48px; border: 0; background: var(--acid); color: var(--ink); font-weight: 800; cursor: pointer; transition: .2s ease; }
.run-button:hover:not(:disabled) { background: var(--orange); color: white; }
.run-button:disabled { cursor: wait; opacity: .75; }

.result-poster { position: relative; min-height: 560px; overflow: hidden; color: #1d1f1c; border: 1px solid rgba(255,255,255,.26); background: #f5d7ad; transition: background .3s ease; }
.result-poster.poster-warm { background: linear-gradient(155deg, #f7e5c7 0 48%, #f3a46d 100%); }
.result-poster.poster-green { background: linear-gradient(160deg, #dce9d1, #f5d8a8 54%, #86a889); }
.result-poster.poster-blue { background: linear-gradient(155deg, #d6eaf0, #8bc0d1 52%, #ff895f 120%); }
.result-visual { position: absolute; width: 390px; height: 320px; border-radius: 50%; left: -130px; bottom: -70px; background: rgba(35,83,62,.88); transform: rotate(-12deg); }
.poster-warm .result-visual { background: rgba(220,101,67,.82); }
.poster-blue .result-visual { background: rgba(26,78,119,.83); }
.result-visual::after { content: ""; position: absolute; width: 200px; height: 200px; border-radius: 50%; left: 235px; top: -140px; background: rgba(255,112,54,.92); }
.result-kicker { position: absolute; top: 24px; left: 24px; font-size: 9px; font-weight: 800; letter-spacing: .18em; border-top: 2px solid; padding-top: 7px; }
.result-copy { position: absolute; z-index: 2; top: 155px; left: 24px; right: 20px; display: flex; flex-direction: column; font-size: 24px; font-weight: 700; line-height: 1.25; letter-spacing: -.05em; }
.result-copy .emphasis { font-size: clamp(30px, 2.5vw, 45px); font-weight: 900; }
.result-visual-note { position: absolute; z-index: 2; top: 282px; left: 24px; right: 20px; font-size: 9px; letter-spacing: .08em; border-left: 1px solid; padding-left: 8px; }
.result-date { position: absolute; z-index: 2; left: 24px; bottom: 25px; color: white; display: flex; align-items: flex-end; gap: 10px; }
.result-date strong { font-size: 82px; line-height: .74; letter-spacing: -.08em; }
.result-date span { font-size: 9px; line-height: 1.2; font-weight: 800; letter-spacing: .06em; }
.demo-watermark { position: absolute; z-index: 3; right: 12px; bottom: 14px; padding: 6px 8px; background: rgba(255,255,255,.78); font-size: 8px; font-weight: 800; letter-spacing: .08em; }

.capability-section { padding: 130px 0; }
.capability-grid { width: min(1400px, calc(100% - 56px)); margin: 0 auto; display: grid; grid-template-columns: repeat(3, 1fr); border-top: 1px solid var(--ink); border-left: 1px solid var(--ink); }
.capability-grid article { position: relative; min-height: 250px; padding: 28px; border-right: 1px solid var(--ink); border-bottom: 1px solid var(--ink); transition: .25s ease; }
.capability-grid article:hover { background: var(--acid); }
.capability-grid article > span { font-size: 11px; font-weight: 800; }
.capability-grid h3 { margin: 58px 0 14px; font-size: 25px; letter-spacing: -.04em; }
.capability-grid p { max-width: 320px; margin: 0; color: #64675f; font-size: 13px; line-height: 1.7; }
.capability-grid i { position: absolute; right: 24px; top: 21px; font-size: 21px; font-style: normal; }

.workflow-section { padding: 130px max(28px, calc((100vw - 1400px) / 2)); background: var(--orange); display: grid; grid-template-columns: .72fr 1.28fr; gap: 100px; }
.workflow-title { position: sticky; top: 80px; align-self: start; }
.workflow-title > p:last-child { max-width: 430px; margin: 30px 0 0; font-size: 14px; line-height: 1.8; }
.workflow-list { margin: 0; padding: 0; list-style: none; border-top: 1px solid var(--ink); }
.workflow-list li { display: grid; grid-template-columns: 55px 130px 1fr; gap: 15px; align-items: center; min-height: 86px; border-bottom: 1px solid var(--ink); }
.workflow-list li > span { font-size: 11px; font-weight: 800; }
.workflow-list h3 { margin: 0; font-size: 22px; }
.workflow-list p { margin: 0; font-size: 13px; }

.standard-section { padding: 130px max(28px, calc((100vw - 1400px) / 2)); background: #d9e6d4; display: grid; grid-template-columns: .85fr 1.15fr; gap: 100px; align-items: center; }
.standard-intro > p:last-child { max-width: 450px; margin-top: 30px; font-size: 14px; line-height: 1.8; }
.quality-card { border: 1px solid var(--ink); background: rgba(255,255,255,.36); box-shadow: 12px 12px 0 var(--ink); display: grid; grid-template-columns: 170px 1fr; }
.quality-score { display: flex; flex-direction: column; justify-content: space-between; padding: 28px; color: var(--cream); background: var(--ink); }
.quality-score strong { font-size: 92px; line-height: .85; letter-spacing: -.08em; }
.quality-score span { font-size: 12px; }
.quality-card ul { margin: 0; padding: 17px 28px; list-style: none; }
.quality-card li { display: grid; grid-template-columns: 105px 1fr; padding: 13px 0; border-bottom: 1px solid var(--line); font-size: 12px; }
.quality-card li:last-child { border-bottom: 0; }
.quality-card li span { color: #64675f; }

.boundaries-section { padding: 130px 0; }
.boundary-grid { width: min(1400px, calc(100% - 56px)); margin: 0 auto; display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
.boundary-card { min-height: 480px; padding: 30px; border: 1px solid var(--ink); display: flex; flex-direction: column; }
.boundary-card.yes { background: var(--acid); }
.boundary-card.no { background: var(--ink); color: var(--cream); }
.boundary-card.human { background: var(--cream); }
.boundary-card > span { font-size: 10px; font-weight: 800; letter-spacing: .16em; }
.boundary-card h3 { margin: 45px 0 auto; font-size: clamp(42px, 4vw, 62px); letter-spacing: -.07em; }
.boundary-card ul { margin: 40px 0 0; padding: 0; list-style: none; }
.boundary-card li { position: relative; padding: 12px 0 12px 21px; border-top: 1px solid currentColor; font-size: 13px; }
.boundary-card li::before { content: "↳"; position: absolute; left: 0; }

.stack-section { padding: 120px max(28px, calc((100vw - 1400px) / 2)); background: var(--ink); color: var(--cream); display: grid; grid-template-columns: .78fr 1.22fr; gap: 100px; }
.stack-list { display: grid; gap: 12px; }
.stack-list article { display: grid; grid-template-columns: 68px 1fr; gap: 20px; align-items: center; padding: 24px; border: 1px solid rgba(255,255,255,.2); }
.stack-list article > span { display: grid; place-items: center; width: 60px; height: 60px; border: 1px solid var(--acid); color: var(--acid); font-size: 19px; font-weight: 900; }
.stack-list h3 { margin: 0 0 7px; font-size: 21px; }
.stack-list p { margin: 0; color: #b8bbb4; font-size: 13px; line-height: 1.6; }

.status-section { padding: 120px max(28px, calc((100vw - 1400px) / 2)); display: grid; grid-template-columns: 150px 1fr .7fr; gap: 60px; align-items: center; }
.status-stamp { display: grid; place-items: center; aspect-ratio: 1; border: 2px solid var(--orange); border-radius: 50%; color: var(--orange); font-size: 13px; line-height: 1.2; font-weight: 900; text-align: center; transform: rotate(-10deg); }
.status-section h2 { font-size: clamp(38px, 4vw, 65px); }
.status-section > div:nth-child(2) > p:last-child { max-width: 700px; color: #62655f; line-height: 1.8; font-size: 13px; }
.status-section ul { margin: 0; padding: 0; list-style: none; border-top: 1px solid var(--line); }
.status-section li { display: flex; gap: 12px; padding: 13px 0; border-bottom: 1px solid var(--line); font-size: 12px; color: #898c84; }
.status-section li.done { color: var(--ink); }
.status-section li.done span { color: #61851a; }

.details-section { padding: 120px max(28px, calc((100vw - 1400px) / 2)); background: #e8e1d2; }
.details-section > h2 { margin-bottom: 58px; }
.details-list { border-top: 1px solid var(--ink); }
.details-list details { border-bottom: 1px solid var(--ink); }
.details-list summary { min-height: 88px; display: grid; grid-template-columns: 55px 1fr 30px; align-items: center; cursor: pointer; list-style: none; font-size: 20px; font-weight: 800; }
.details-list summary::-webkit-details-marker { display: none; }
.details-list summary span { font-size: 10px; }
.details-list summary i { font-style: normal; font-size: 24px; transition: transform .2s ease; }
.details-list details[open] summary i { transform: rotate(45deg); }
.details-list details > p { max-width: 820px; margin: 0 0 34px 55px; color: #5f625b; line-height: 1.8; font-size: 14px; }
.details-list code { padding: 3px 6px; background: rgba(255,255,255,.6); color: var(--ink); }

footer { min-height: 120px; padding: 28px max(28px, calc((100vw - 1400px) / 2)); background: var(--ink); color: white; display: flex; justify-content: space-between; align-items: center; font-size: 12px; }
footer > p { color: #b3b6af; }
footer > div { display: flex; gap: 10px; align-items: center; font-weight: 700; letter-spacing: .08em; }

@media (max-width: 1100px) {
  .nav-links { display: none; }
  .demo-layout { grid-template-columns: .65fr 1.35fr; }
  .result-poster { grid-column: 1 / -1; min-height: 620px; }
  .result-copy { font-size: 32px; }
  .result-copy .emphasis { font-size: 58px; }
  .workflow-section, .standard-section, .stack-section { grid-template-columns: 1fr; gap: 60px; }
  .workflow-title { position: static; }
  .status-section { grid-template-columns: 120px 1fr; }
  .status-section ul { grid-column: 2; }
}

@media (max-width: 820px) {
  .nav-shell, .hero, .section-heading, .demo-layout, .capability-grid, .boundary-grid { width: calc(100% - 32px); }
  .nav-meta { font-size: 0; }
  .hero { grid-template-columns: 1fr; padding-top: 54px; gap: 36px; }
  h1 { font-size: clamp(56px, 16vw, 90px); }
  .hero-stage { min-height: 530px; }
  .poster-card { width: min(330px, 82vw); }
  .hero-stats { flex-wrap: wrap; gap: 20px 0; }
  .trust-strip { flex-wrap: wrap; gap: 10px 15px; padding-block: 18px; }
  .trust-strip > span { width: 100%; text-align: center; }
  .section-heading { grid-template-columns: 1fr; gap: 25px; }
  .demo-layout { grid-template-columns: 1fr; }
  .scenario-picker { display: grid; grid-template-columns: repeat(3, 1fr); }
  .scenario-picker button { display: block; }
  .scenario-picker button span, .scenario-picker button small { display: none; }
  .demo-console { min-height: 520px; }
  .result-poster { grid-column: auto; min-height: 620px; }
  .capability-grid { grid-template-columns: repeat(2, 1fr); }
  .boundary-grid { grid-template-columns: 1fr; }
  .boundary-card { min-height: 420px; }
  .status-section { grid-template-columns: 90px 1fr; gap: 35px; }
  .quality-card { grid-template-columns: 125px 1fr; }
  .quality-score { padding: 20px; }
  .quality-score strong { font-size: 66px; }
  footer { align-items: flex-start; gap: 25px; flex-direction: column; }
}

@media (max-width: 540px) {
  .brand span:last-child { font-size: 10px; }
  .hero { padding-bottom: 60px; }
  .hero-lead { font-size: 16px; }
  .hero-stats div { min-width: 50%; margin-bottom: 14px; }
  .poster-copy { font-size: 24px; }
  .poster-copy strong { font-size: 38px; }
  .experience-section, .capability-section, .workflow-section, .standard-section, .boundaries-section, .stack-section, .status-section, .details-section { padding-block: 90px; }
  .capability-grid { grid-template-columns: 1fr; }
  .workflow-list li { grid-template-columns: 38px 82px 1fr; }
  .workflow-list h3 { font-size: 18px; }
  .workflow-list p { font-size: 11px; }
  .quality-card { grid-template-columns: 1fr; }
  .quality-score { min-height: 140px; }
  .quality-card li { grid-template-columns: 90px 1fr; }
  .status-section { grid-template-columns: 1fr; }
  .status-stamp { width: 100px; }
  .status-section ul { grid-column: 1; }
  .details-list summary { grid-template-columns: 40px 1fr 24px; font-size: 16px; }
  .details-list details > p { margin-left: 40px; }
}

@media (prefers-reduced-motion: reduce) {
  * { scroll-behavior: auto !important; transition-duration: 0.01ms !important; }
}