:root {
  color-scheme: dark;
  --bg: #0d1211;
  --surface: #141b19;
  --soft: #19211e;
  --ink: #f1ecdf;
  --muted: #adb4aa;
  --accent: #d6b57c;
  --line: #526158;
  --rule: #303d36;
  --stage: #101714;
  --focus: #e4c488;
  --sans: -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", sans-serif;
  --serif: "Songti SC", "STSong", "Noto Serif CJK SC", "SimSun", serif;
  --gutter: clamp(24px, 5.55vw, 80px);
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.75;
  background: var(--bg);
  color: var(--ink);
}
:root[data-theme="light"] {
  color-scheme: light;
  --bg: #f5f2e9;
  --surface: #fffcf5;
  --soft: #e8e3d7;
  --ink: #202924;
  --muted: #58645c;
  --accent: #75551e;
  --line: #8b958b;
  --rule: #d2d5c9;
  --stage: #ebe7dc;
  --focus: #75551e;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: var(--header-offset, 110px); }
body, h1, h2, h3, h4, p, figure, dl, dd { margin: 0; }
button, a { -webkit-tap-highlight-color: transparent; }
button { font: inherit; cursor: pointer; }
a { color: inherit; text-decoration: none; }
button { color: inherit; }
img { display: block; max-width: 100%; height: auto; }
[hidden] { display: none !important; }
:focus-visible { outline: 3px solid var(--focus); outline-offset: 5px; }
:where(a, button, summary) { touch-action: manipulation; }
:where(section, article, figure, .hero-copy) { min-width: 0; }
::selection { background: var(--accent); color: var(--bg); }
.wrap { width: min(1280px, calc(100% - var(--gutter) * 2)); margin-inline: auto; }
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip-path: inset(50%); white-space: nowrap; border: 0; }
.skip-link { position: fixed; top: 12px; left: 24px; z-index: 30; padding: 10px 18px; background: var(--ink); color: var(--bg); transform: translateY(-160%); }
.skip-link:focus { transform: none; }
.site-header { position: sticky; top: 0; z-index: 10; background: var(--bg); border-bottom: 1px solid var(--rule); }
.header-inner { flex-wrap: wrap; padding-block: 12px; min-height: 80px; display: flex; justify-content: space-between; align-items: center; gap: 24px; }
.wordmark { display: inline-flex; align-items: center; gap: 14px; font-family: Georgia, var(--serif); font-size: 30px; letter-spacing: -.04em; line-height: 1.4; white-space: nowrap; }
.wordmark img { width: 40px; height: 40px; flex-shrink: 0; border-radius: 9px; }
.wordmark span { font-family: var(--serif); font-size: 18px; letter-spacing: .08em; }
nav { display: flex; flex-wrap: wrap; gap: clamp(12px, 1.6vw, 24px); }
nav a { font-size: 14px; padding-block: 12px; color: var(--muted); border-bottom: 1px solid transparent; transition: color .15s, border-color .15s; }
nav a:hover { color: var(--ink); border-color: var(--accent); }
.product { padding-block: 48px 64px; }
.hero-grid { display: grid; grid-template-columns: 1.1fr .9fr; align-items: center; gap: 64px; }
.hero-copy { padding-block: 32px; }
.eyebrow { display: flex; align-items: center; gap: 12px; color: var(--accent); font-size: 13px; line-height: 1.6; letter-spacing: .06em; }
.small-rule { display: inline-block; height: 1px; width: 28px; background: var(--accent); }
h1, h2, h3 { font-weight: 400; text-wrap: balance; }
h1 { font-family: var(--serif); font-size: clamp(40px, 4.8vw, 70px); line-height: 1.25; letter-spacing: -.04em; margin: 28px 0; }
h1 span { color: var(--accent); }
.hero-lead { font-size: 20px; line-height: 1.85; }
.hero-description { max-width: 29em; color: var(--muted); margin-top: 20px; }
.hero-actions { display: flex; flex-wrap: wrap; align-items: center; gap: 24px; margin-top: 36px; }
.button { min-height: 48px; display: inline-flex; align-items: center; justify-content: center; gap: 24px; padding: 12px 24px; border: 1px solid transparent; border-radius: 4px; line-height: 1.5; font-size: 16px; transition: background .16s, border-color .16s, transform .16s; }
.primary { background: var(--ink); color: var(--bg); }
.secondary { background: transparent; border-color: var(--line); }
.text-link { display: inline-flex; flex-wrap: wrap; align-items: center; column-gap: 8px; row-gap: 2px; padding-block: 10px; font-size: 14px; text-decoration: underline; text-underline-offset: 6px; text-decoration-color: var(--line); transition: text-decoration-color .15s; }
.text-link:hover { text-decoration-color: var(--accent); }
.external-note { font-size: 13px; color: var(--muted); text-decoration: none; }
.status-note { color: var(--muted); font-size: 13px; margin-top: 16px; }
.hero-foot { border-top: 1px solid var(--rule); display: flex; flex-wrap: wrap; gap: 8px 28px; font-size: 13px; color: var(--muted); margin-top: 48px; padding-top: 22px; }
.hero-visual { padding: 24px 32px; background: var(--stage); border: 1px solid var(--rule); display: flex; flex-direction: column; align-items: center; gap: 16px; }
.visual-heading { display: flex; justify-content: space-between; width: 100%; font-size: 13px; color: var(--muted); padding-bottom: 16px; border-bottom: 1px solid var(--rule); }
.screen-link { display: block; width: min(100%, 320px); border-radius: 14px; }
.screen-link img { width: 100%; border-radius: 14px; outline: 1px solid var(--rule); }
.hero-visual .screen-link { width: min(100%, 290px); }
.zoom-label { min-height: 44px; display: flex; justify-content: space-between; align-items: center; padding: 12px 0; font-size: 13px; color: var(--muted); }
.screen-link:hover .zoom-label { color: var(--ink); }
figcaption { font-size: 14px; color: var(--muted); }
.section { padding-block: 104px; border-top: 1px solid var(--rule); }
.section-heading { display: flex; justify-content: space-between; gap: 32px; align-items: end; margin-bottom: 48px; }
h2 { font-family: var(--serif); font-size: clamp(34px, 3.35vw, 48px); line-height: 1.35; margin-top: 16px; letter-spacing: -.025em; }
.section-intro { flex-shrink: 0; font-size: 15px; line-height: 1.8; color: var(--muted); }
.demo { background: var(--surface); }
.step-controls { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 0; border-bottom: 1px solid var(--rule); }
.step-controls button { position: relative; border: 0; border-bottom: 2px solid transparent; background: transparent; text-align: left; padding: 18px 12px; min-height: 60px; color: var(--muted); transition: color .15s, background .15s; }
.step-controls button span { margin-right: 16px; font-size: 13px; font-variant-numeric: tabular-nums; }
.step-controls button[aria-pressed="true"] { font-weight: 600; color: var(--ink); border-bottom-color: var(--accent); background: var(--soft); }
.step-controls button:hover { color: var(--ink); background: var(--soft); }
.step-panel { display: grid; grid-template-columns: 1fr 1fr; gap: 64px; padding-top: 48px; align-items: center; }
.step-panel + .step-panel { margin-top: 48px; border-top: 1px solid var(--rule); }
.enhanced .step-panel { margin-top: 0; border: 0; }
.step-copy { max-width: 470px; }
.step-index { font-family: Georgia, serif; font-size: 80px; letter-spacing: -.06em; line-height: 1; margin-bottom: 32px; color: var(--accent); }
.step-index span { letter-spacing: 0; font-family: var(--sans); font-size: 14px; color: var(--muted); }
h3 { font-family: var(--serif); font-size: 32px; line-height: 1.5; }
.step-copy h3 { margin-top: 12px; }
.step-description { margin-top: 28px; }
.step-description dt { font-size: 14px; color: var(--accent); margin-bottom: 4px; }
.step-description dd { margin-bottom: 20px; }
.evidence-note { padding-top: 20px; border-top: 1px solid var(--rule); color: var(--muted); font-size: 14px; }
.content-label { display: inline-block; color: var(--muted); font-size: 13px; margin-top: 20px; }
.step-visual, .project-visual { padding: 32px; background: var(--stage); border: 1px solid var(--rule); display: flex; justify-content: center; }
.demo-note { color: var(--muted); font-size: 13px; padding-top: 32px; border-top: 1px solid var(--rule); margin-top: 32px; }
.ai-case { background: var(--soft); }
.case-grid > div { padding-top: 20px; border-top: 1px solid var(--line); }
.case-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 40px; }
.case-grid h3 { font-family: var(--sans); font-size: 20px; margin-block: 14px; }
.case-grid > div > p:last-child { color: var(--muted); }
.evidence-boundary { display: grid; grid-template-columns: 140px 1fr; gap: 24px; padding-top: 24px; margin-top: 32px; border-top: 1px solid var(--rule); color: var(--muted); font-size: 14px; }
.evidence-boundary > span { color: var(--accent); }
.ai-case.section { padding-block: 72px; }
.contribution { background: var(--surface); }
.project-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 64px; align-items: center; }
.project-copy { max-width: 470px; }
.project-copy h3 { margin-block: 16px 24px; }
.project-copy > p:not(.eyebrow):not(.state-label) { margin-top: 20px; }
.project-lead { font-size: 20px; }

.work-list { list-style: none; padding: 0; margin: 56px 0 0; display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 40px; border-top: 1px solid var(--rule); }
.work-list li { display: flex; gap: 20px; padding-block: 28px; }
.work-list li > span { color: var(--accent); font-size: 13px; padding-top: 7px; }
.work-list h3 { font-family: var(--sans); font-size: 20px; margin-bottom: 12px; }
.work-list p { color: var(--muted); }
.theme-toggle { font-size: 14px; padding: 9px 14px; gap: 8px; white-space: nowrap; }
.theme-toggle:disabled { cursor: default; }
.theme-policy { margin-top: 20px; color: var(--muted); font-size: 14px; }
.upgrade-block { border-top: 1px solid var(--rule); padding-block: 64px; }
.upgrade-block:last-child { padding-bottom: 0; }
.appearance-block { display: grid; grid-template-columns: .8fr 1.2fr; gap: 48px 64px; align-items: start; }
.appearance-block > .proof-pair { width: 100%; margin: 0; }
.appearance-block > .supporting-proof { grid-column: 1 / -1; margin: 0; border-top: 1px solid var(--rule); }
.icon-context { align-self: center; max-width: 32em; }
.icon-context h4 { font-family: var(--serif); font-size: 26px; font-weight: 400; margin: 12px 0 20px; }
.icon-context > p:last-child { color: var(--muted); }
.upgrade-copy { max-width: 680px; }
.upgrade-copy h3 { margin-block: 12px 24px; }
.feedback-description dt { color: var(--accent); font-size: 14px; margin-bottom: 4px; }
.feedback-description dd { margin-bottom: 20px; }
.proof-pair { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 32px; max-width: 640px; margin: 32px auto 0; }
.proof-pair figure { min-width: 0; }
.proof-pair .screen-link { margin-inline: auto; }
.proof-pair figcaption { max-width: 320px; margin-inline: auto; }
.icon-proof { max-width: 640px; }
.icon-proof .screen-link { max-width: 260px; }
.supporting-proof { margin-top: 32px; }
.supporting-proof summary { cursor: pointer; padding: 14px 0; color: var(--accent); text-decoration: underline; text-underline-offset: 5px; }
.upgrade-split { display: grid; grid-template-columns: 1fr 1fr; gap: 64px; align-items: center; }
.upgrade-split > figure { width: 100%; padding: 32px; justify-self: center; background: var(--stage); border: 1px solid var(--rule); }
.upgrade-split > figure .screen-link { margin-inline: auto; }
.upgrade-split > figure figcaption { max-width: 320px; margin-inline: auto; }
.upgrade-split[aria-labelledby="undo-title"] .screen-link { max-width: 280px; }
.optional-note { margin-top: 20px; padding: 16px; background: var(--soft); color: var(--muted); font-size: 14px; }
.delivery-line { border-top: 1px solid var(--rule); padding-top: 24px; display: flex; justify-content: space-between; gap: 24px; color: var(--muted); font-size: 13px; }
.delivery-line span { color: var(--accent); margin-right: 12px; }
.state-label { font-size: 14px; line-height: 1.7; color: var(--accent); margin-block: 20px; padding: 10px 14px; background: var(--soft); border-left: 2px solid var(--accent); }
.hero-description strong { color: var(--ink); font-weight: 500; }
.hero-foot a { color: var(--accent); text-decoration: underline; text-underline-offset: 5px; }
footer { padding-block: 40px; border-top: 1px solid var(--rule); }
.footer-inner { display: flex; align-items: center; justify-content: space-between; gap: 24px; }
.footer-inner p { font-size: 13px; color: var(--muted); }
dialog { width: min(100% - 32px, 1100px); max-width: none; height: min(94dvh, 1100px); max-height: none; padding: 0; border: 1px solid var(--line); background: var(--surface); color: var(--ink); border-radius: 8px; }
dialog::backdrop { background: rgb(0 0 0 / .86); }
.viewer-shell { display: flex; flex-direction: column; height: 100%; padding: 24px; }
.viewer-header { display: flex; align-items: center; justify-content: space-between; gap: 20px; }
.viewer-header h2 { font-family: var(--sans); font-size: 18px; margin: 0; }
.viewer-actions { display: flex; gap: 12px; flex-shrink: 0; }
.viewer-actions .button { padding: 8px 16px; min-height: 44px; font-size: 14px; gap: 12px; }
#viewer-description { color: var(--muted); font-size: 13px; margin-block: 12px 20px; }
.viewer-canvas { min-height: 0; flex: 1; overflow: auto; overscroll-behavior: contain; background: var(--bg); border-radius: 4px; }
#viewer-image { margin-inline: auto; width: auto; max-width: 100%; height: 100%; object-fit: contain; }
.viewer-canvas.is-zoomed #viewer-image { width: 710px; height: auto; max-width: none; }
.viewer-open { overflow: hidden; }
@media (hover: hover) and (pointer: fine) {
  .button:hover { transform: translateY(-1px); }
  .primary:hover { background: var(--accent); }
  .secondary:hover { background: var(--soft); border-color: var(--accent); }
  .button:active { transform: translateY(1px); }
  .screen-link:hover .zoom-label span { transform: translate(2px, -2px); }
  .zoom-label span { transition: transform .16s; }
}
@media (max-width: 1050px) {
  .hero-grid { grid-template-columns: 1.1fr .9fr; gap: 32px; }
  .hero-visual { padding: 20px; }
  .appearance-block { grid-template-columns: 1fr; gap: 32px; }
  .appearance-block > .proof-pair { margin-inline: auto; }
  .icon-context { margin-top: 20px; }
  .step-visual, .project-visual, .upgrade-split > figure { padding: 20px; }
  h1 { font-size: 40px; }
  .hero-lead { font-size: 18px; }
  .desktop-break { display: none; }
  .hero-actions { gap: 12px; }
  .hero-foot { margin-top: 28px; }
  .section { padding-block: 80px; }
  .section-heading { align-items: start; }
  .section-intro { max-width: 260px; }
  .step-panel, .project-grid { gap: 32px; }
  .case-grid, .work-list, .upgrade-split { gap: 24px; }
  h3 { font-size: 26px; }
  .step-index { font-size: 52px; margin-bottom: 24px; }
}
@media (max-width: 700px) {
  html { scroll-padding-top: var(--header-offset, 190px); }
  .header-inner { min-height: 104px; flex-direction: row; align-items: flex-start; justify-content: space-between; gap: 8px; padding-block: 10px; }
  .wordmark { font-size: 26px; }
  .wordmark span { font-size: 16px; }
  nav { order: 3; width: 100%; justify-content: space-between; gap: 12px; flex-wrap: wrap; }
  nav a { min-height: 44px; display: inline-flex; align-items: center; font-size: 13px; padding-block: 8px; }
  .product { padding-block: 40px 56px; }
  .hero-grid { grid-template-columns: 1fr; gap: 40px; }
  .hero-copy { padding: 0; }
  h1 { font-size: clamp(34px, 10.25vw, 48px); margin-block: 24px; }
  .hero-lead { font-size: 18px; }
  .hero-actions { margin-top: 28px; }
  .hero-actions .primary { width: 100%; justify-content: space-between; }
  .hero-actions .text-link { padding-block: 6px; }
  .hero-foot { gap: 4px 16px; font-size: 13px; }
  .hero-visual { padding: 20px; }
  .hero-visual .screen-link { width: min(100%, 300px); }
  .section { padding-block: 64px; }
  .section-heading { flex-direction: column; gap: 20px; margin-bottom: 32px; }
  .section-intro { max-width: none; }
  h2 { font-size: 30px; }
  .step-controls { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .step-controls button { padding: 14px 8px; font-size: 15px; }
  .step-controls button span { margin-right: 10px; }
  .step-panel { grid-template-columns: 1fr; gap: 32px; padding-top: 32px; }
  .step-copy { max-width: none; }
  .step-index { font-size: 44px; margin-bottom: 20px; }
  h3 { font-size: 22px; }
  .step-description { margin-top: 24px; }
  .screen-link { width: min(100%, 320px); }
  .step-visual, .project-visual, .upgrade-split > figure { padding: 20px; }
  .upgrade-block { padding-block: 40px; }
  .proof-pair .screen-link, .icon-proof .screen-link { max-width: 300px; }
  .icon-context h4 { font-size: 23px; }
  .case-grid, .project-grid, .work-list, .upgrade-split { grid-template-columns: 1fr; gap: 28px; }
  .proof-pair { grid-template-columns: 1fr; gap: 32px; }
  .proof-pair figure { justify-self: center; }
  .theme-toggle { padding-inline: 10px; font-size: 13px; }
  .work-list { margin-top: 36px; gap: 0; }
  .work-list li + li { border-top: 1px solid var(--rule); }
  .project-copy { max-width: none; }
  .project-lead { font-size: 18px; }
  .delivery-line { flex-direction: column; gap: 12px; }
  .evidence-boundary { grid-template-columns: 1fr; gap: 12px; }
  .ai-case.section { padding-block: 56px; }
  .footer-inner { align-items: flex-start; flex-direction: column; gap: 16px; }
  dialog { width: calc(100% - 16px); height: calc(100dvh - 16px); }
  .viewer-shell { padding: 16px; }
  .viewer-header { flex-wrap: wrap; gap: 12px; }
  .viewer-header h2 { font-size: 16px; }
  .viewer-actions { justify-content: space-between; width: 100%; }
  #viewer-description { margin-bottom: 12px; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation: none !important; transition: none !important; }
  .button:hover, .button:active, .screen-link:hover .zoom-label span { transform: none; }
}