:root {
  color-scheme: light;
  --primary: #cc785c;
  --primary-active: #a9583e;
  --ink: #141413;
  --body: #3d3d3a;
  --muted: #6c6a64;
  --muted-soft: #8e8b82;
  --line: #e6dfd8;
  --line-soft: #ebe6df;
  --canvas: #faf9f5;
  --soft: #f5f0e8;
  --card: #efe9de;
  --cream-strong: #e8e0d2;
  --dark: #181715;
  --dark-raised: #252320;
  --on-dark: #faf9f5;
  --on-dark-soft: #a09d96;
  --teal: #5db8a6;
  --amber: #e8a55a;
  --serif: "Iowan Old Style", "Palatino Linotype", "Noto Serif SC", "Songti SC", serif;
  --sans: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  --mono: "JetBrains Mono", "SFMono-Regular", Consolas, "Liberation Mono", monospace;
  --container: 1180px;
}

*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 84px; }
body { margin: 0; min-width: 320px; overflow-x: hidden; background: var(--canvas); color: var(--ink); font: 16px/1.65 var(--sans); text-rendering: optimizeLegibility; }
a { color: inherit; }
button { color: inherit; font: inherit; }
::selection { color: white; background: var(--primary); }
:focus-visible { outline: 3px solid color-mix(in srgb, var(--primary) 45%, transparent); outline-offset: 3px; }
.container { width: min(var(--container), calc(100% - 40px)); margin-inline: auto; }
.sr-only { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0, 0, 0, 0); white-space: nowrap; }
.skip-link { position: fixed; z-index: 100; left: 16px; top: -60px; padding: 10px 14px; border-radius: 8px; color: white; background: var(--dark); transition: top .2s; }
.skip-link:focus { top: 16px; }
.progress { position: fixed; z-index: 90; inset: 0 0 auto; height: 2px; background: transparent; }
.progress span { display: block; width: 100%; height: 100%; background: var(--primary); transform: scaleX(0); transform-origin: left center; will-change: transform; }

.site-header { position: sticky; top: 0; z-index: 50; background: color-mix(in srgb, var(--canvas) 94%, transparent); border-bottom: 1px solid transparent; -webkit-backdrop-filter: blur(10px); backdrop-filter: blur(10px); transition: border-color .2s; }
.site-header.scrolled { border-color: var(--line-soft); }
.nav-wrap { min-height: 68px; display: flex; align-items: center; justify-content: space-between; gap: 24px; }
.wordmark { display: inline-flex; align-items: center; color: var(--ink); font-weight: 650; text-decoration: none; letter-spacing: -.02em; }
.spark { margin-right: 9px; font-size: 18px; }
.site-nav { display: flex; align-items: center; gap: 26px; }
.site-nav a { color: var(--ink); font-size: 14px; font-weight: 520; text-decoration: none; }
.site-nav a:not(.nav-cta) { text-decoration-line: underline; text-decoration-color: transparent; text-underline-offset: 6px; transition: text-decoration-color .2s; }
.site-nav a:not(.nav-cta):hover, .site-nav a[aria-current="true"] { text-decoration-color: var(--primary); }
.site-nav .nav-cta { position: relative; min-height: 42px; display: inline-flex; align-items: center; overflow: hidden; padding: 0 18px; border-radius: 8px; color: white; background: var(--primary); font-size: 14px; font-weight: 520; will-change: transform; animation: welcome-breathe 4s ease-in-out infinite; }
.site-nav .nav-cta::after { content: ""; position: absolute; inset: 0 auto 0 -45%; width: 34%; background: linear-gradient(100deg, transparent, rgba(255, 255, 255, .32), transparent); transform: translate3d(0, 0, 0) skewX(-18deg); will-change: transform; animation: welcome-shine 4s ease-in-out infinite; }
@keyframes welcome-breathe { 0%, 72%, 100% { transform: translate3d(0, 0, 0); } 78% { transform: translate3d(0, -2px, 0); } 84% { transform: translate3d(0, 0, 0); } }
@keyframes welcome-shine { 0%, 70% { transform: translate3d(0, 0, 0) skewX(-18deg); } 86%, 100% { transform: translate3d(500%, 0, 0) skewX(-18deg); } }
.menu-button { display: none; width: 44px; height: 44px; border: 1px solid var(--line); border-radius: 8px; background: var(--canvas); }
.menu-button > span:not(.sr-only) { display: block; width: 18px; height: 1.5px; margin: 5px auto; background: var(--ink); transition: transform .2s; }

.hero { min-height: 650px; display: flex; align-items: center; padding-block: 90px 104px; }
.hero-copy { width: 100%; }
.hero-layout { display: grid; grid-template-columns: 1.05fr .95fr; gap: clamp(56px, 7vw, 96px); align-items: center; }
.eyebrow { margin: 0 0 16px; color: var(--muted); font-size: 12px; font-weight: 600; letter-spacing: .15em; text-transform: uppercase; }
.hero h1, .section h2, .contact-card h2 { margin: 0; font: 400 clamp(52px, 6.6vw, 78px)/1.04 var(--serif); letter-spacing: -.04em; }
.hero h1 em { color: var(--primary); font-style: normal; }
.hero-lead { max-width: 640px; margin: 0; color: var(--body); font-size: 18px; line-height: 1.75; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 28px; }
.button { min-height: 44px; display: inline-flex; align-items: center; justify-content: center; padding: 0 20px; border: 1px solid transparent; border-radius: 8px; cursor: pointer; font-size: 14px; font-weight: 600; text-decoration: none; }
.button-primary { color: white; background: var(--primary); }
.button-primary:active { background: var(--primary-active); }
.button-secondary { border-color: var(--line); background: var(--canvas); }
.signal-band { border-block: 1px solid var(--line); }
.signal-grid { display: grid; grid-template-columns: repeat(4, 1fr); }
.signal-grid div { padding: 24px 14px; }
.signal-grid strong, .signal-grid span { display: block; }
.signal-grid strong { font-size: 18px; }
.signal-grid span { margin-top: 2px; color: var(--muted); font-size: 13px; }

.section { padding-block: 108px; }
.section-soft { background: var(--soft); }
.section-dark { color: var(--on-dark); background: var(--dark); }
.section-intro h2 { font-size: clamp(40px, 5vw, 58px); }
.section-intro { display: grid; grid-template-columns: 1.2fr .8fr; gap: 54px; align-items: end; margin-bottom: 48px; }
.section-intro h2 { margin: 0; }
.project-intro h2 em { color: var(--primary); font-style: normal; }
.section-intro > p { margin: 0; color: var(--muted); font-size: 17px; }
.section-dark .section-intro > p, .section-dark .eyebrow { color: var(--on-dark-soft); }

.skill-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.skill-card { position: relative; min-height: 390px; padding: 32px; border: 1px solid var(--line); border-radius: 12px; background: var(--canvas); }
.skill-card.dark { color: var(--on-dark); border-color: var(--dark); background: var(--dark); }
.skill-card.sage { color: var(--ink); border-color: #c8ddd6; background: #dfece7; }
.skill-card.coral { color: white; border-color: var(--primary); background: var(--primary); }
.skill-index { color: var(--muted); font: 12px var(--mono); }
.dark .skill-index { color: var(--on-dark-soft); }
.sage .skill-index { color: #4f7c72; }
.coral .skill-index { color: rgba(255, 255, 255, .72); }
.skill-card h3 { margin: 48px 0 6px; font: 400 31px/1.15 var(--serif); }
.skill-card > p { margin: 0; color: var(--muted); }
.dark > p { color: var(--on-dark-soft); }
.sage > p { color: #526b65; }
.coral > p { color: rgba(255, 255, 255, .8); }
.skill-card ul { margin: 28px 0 0; padding-left: 1.15em; }
.skill-card li { margin: 9px 0; }
.skill-card li::marker { color: var(--primary); }
.dark li::marker { color: var(--teal); }
.sage li::marker { color: #3f8c7c; }
.coral li::marker { color: white; }
.tool-row { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 20px; }
.tool-row span { padding: 7px 12px; border-radius: 999px; color: var(--body); background: var(--card); font-size: 13px; }

.featured-project { display: grid; grid-template-columns: 1.05fr .95fr; overflow: hidden; border-radius: 12px; color: var(--on-dark); background: var(--dark); }
.featured-copy { padding: 42px; }
.project-meta { display: flex; justify-content: space-between; gap: 20px; color: var(--on-dark-soft); font: 11px var(--mono); letter-spacing: .05em; }
.featured-copy h3 { margin: 58px 0 10px; font: 400 48px/1.08 var(--serif); }
.project-lead { max-width: 570px; color: #d9d4cc; font-size: 18px; }
.project-tags { display: flex; flex-wrap: wrap; gap: 7px; margin-top: 26px; }
.project-tags span { padding: 5px 9px; border: 1px solid currentColor; border-radius: 999px; color: inherit; font: 11px var(--mono); opacity: .72; }
.project-diagram { position: relative; min-height: 410px; overflow: hidden; background: var(--dark-raised); }
.project-diagram::before, .project-diagram::after { content: ""; position: absolute; border: 1px solid #48453f; border-radius: 50%; inset: 15%; }
.project-diagram::after { inset: 30%; }
.diagram-core { position: absolute; z-index: 2; inset: 50% auto auto 50%; width: 110px; height: 110px; display: grid; place-content: center; border-radius: 50%; transform: translate(-50%, -50%); color: var(--ink); background: var(--primary); font: 400 25px var(--serif); text-align: center; }
.diagram-core small { display: block; font: 10px var(--mono); }
.node { position: absolute; z-index: 2; padding: 7px 10px; border: 1px solid #4b4842; border-radius: 6px; color: #d8d2ca; background: var(--dark); font: 11px var(--mono); }
.node-a { left: 10%; top: 14%; }.node-b { right: 10%; top: 19%; }.node-c { left: 8%; bottom: 15%; }.node-d { right: 8%; bottom: 14%; }
.case-details { grid-column: 1 / -1; border-top: 1px solid #302f2b; }
.case-details summary { display: flex; justify-content: space-between; padding: 20px 42px; cursor: pointer; list-style: none; }
.case-details summary::-webkit-details-marker, .project-story summary::-webkit-details-marker { display: none; }
.case-details summary span { transition: transform .2s; }
.case-details[open] summary span { transform: rotate(45deg); }
.case-content { display: grid; grid-template-columns: 1fr 1fr; gap: 1px; padding-top: 1px; background: #302f2b; }
.case-content article { padding: 30px 42px; background: var(--dark); }
.case-content h4 { margin: 0 0 9px; font-size: 16px; }
.case-content p { margin: 0; color: var(--on-dark-soft); font-size: 14px; }
.project-list { margin-top: 20px; border-top: 1px solid var(--line); }
.project-story { border-bottom: 1px solid var(--line); }
.project-story summary { display: grid; grid-template-columns: 70px 1fr auto; gap: 20px; align-items: center; min-height: 104px; cursor: pointer; list-style: none; }
.story-no { color: var(--muted); font: 12px var(--mono); }
.story-main { display: grid; gap: 4px; }
.story-main strong { font: 400 25px var(--serif); }
.story-main small { color: var(--muted); font-size: 13px; }
.story-action { color: var(--primary); font-size: 13px; }
.project-story[open] .story-action { font-size: 0; }
.project-story[open] .story-action::after { content: "收起案例"; font-size: 13px; }
.story-content { padding: 4px 0 32px 90px; max-width: 940px; }
.story-content > p { color: var(--body); font-size: 18px; }
.story-content li { margin: 8px 0; color: var(--body); }
.story-content .project-tags { color: var(--primary); }

.ai-practice-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 16px; }
.ai-practice-card { min-height: 245px; padding: 30px; border: 1px solid var(--line); border-radius: 12px; background: var(--canvas); }
.ai-practice-card > span { color: var(--primary); font: 11px var(--mono); letter-spacing: .05em; text-transform: uppercase; }
.ai-practice-card h3 { margin: 42px 0 10px; font: 400 27px/1.15 var(--serif); }
.ai-practice-card p { margin: 0; color: var(--body); }
.ai-toolkit { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 20px; }
.ai-toolkit span { padding: 7px 12px; border: 1px solid var(--line); border-radius: 999px; color: var(--body); background: var(--canvas); font: 12px var(--mono); }

.timeline { border-top: 1px solid #373530; }
.timeline-item { display: grid; grid-template-columns: 170px 1fr; gap: 30px; padding: 30px 0; border-bottom: 1px solid #373530; }
.timeline-item time { color: var(--on-dark-soft); font: 12px var(--mono); }
.timeline-item h3 { margin: 0 0 5px; font: 400 27px var(--serif); }
.timeline-item p { margin: 0 0 6px; color: var(--primary); }
.timeline-item span { color: var(--on-dark-soft); }

.contact-card { padding: clamp(36px, 7vw, 72px); border-radius: 12px; color: white; background: var(--primary); }
.contact-card .eyebrow { color: rgba(255, 255, 255, .72); }
.contact-card h2 { max-width: 850px; font-size: clamp(42px, 6vw, 68px); }
.contact-grid { display: grid; grid-template-columns: minmax(0, 1fr) 300px; gap: clamp(36px, 6vw, 78px); align-items: center; }
.contact-copy > p:not(.eyebrow) { max-width: 690px; color: rgba(255, 255, 255, .82); font-size: 18px; }
.contact-actions { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 28px; }
.button-inverse { color: var(--ink); background: var(--canvas); }
.button-ghost { border-color: rgba(255, 255, 255, .45); color: white; background: transparent; }
.contact-wechat { padding: 18px; border-radius: 12px; color: var(--on-dark); background: var(--dark); }
.contact-qr { width: 100%; aspect-ratio: 1; overflow: hidden; padding: 8px; border-radius: 9px; background: white; }
.contact-qr img { width: 100%; height: 100%; display: block; border-radius: 5px; object-fit: cover; object-position: center center; }
.contact-wechat > div:last-child { display: grid; gap: 2px; padding: 14px 2px 2px; }
.contact-wechat strong { font: 400 22px var(--serif); }
.contact-wechat span { color: var(--on-dark-soft); font-size: 12px; }
.contact-foot { display: flex; flex-wrap: wrap; gap: 28px; margin-top: 60px; padding-top: 20px; border-top: 1px solid rgba(255, 255, 255, .25); font-size: 13px; }
.contact-foot a { text-decoration: none; }

.site-footer { padding-block: 64px 42px; color: var(--on-dark-soft); background: var(--dark); }
.footer-grid { display: grid; grid-template-columns: 1.4fr .8fr 1fr; gap: 40px; }
.footer-mark { color: var(--on-dark); }
.footer-grid p { font-size: 13px; }
.footer-links { display: grid; grid-template-columns: 1fr 1fr; gap: 8px 20px; }
.footer-links a { color: var(--on-dark-soft); text-decoration: none; font-size: 13px; }
.footer-actions { display: flex; align-items: flex-end; flex-direction: column; gap: 12px; font-size: 12px; }
.footer-actions button { padding: 0; border: 0; color: var(--on-dark); background: none; cursor: pointer; text-decoration: underline; text-underline-offset: 5px; }
.toast { position: fixed; z-index: 100; right: 20px; bottom: 20px; padding: 11px 16px; border-radius: 8px; color: white; background: var(--dark); opacity: 0; transform: translate3d(0, 12px, 0); pointer-events: none; transition: opacity .25s, transform .25s; }
.toast.show { opacity: 1; transform: none; }

.js .reveal { opacity: 0; transform: translate3d(0, 16px, 0); backface-visibility: hidden; transition: opacity .55s ease, transform .55s ease; }
.js .reveal.is-visible { opacity: 1; transform: translate3d(0, 0, 0); }

@media (max-width: 860px) {
  .container { width: calc(100% - 28px); }
  .menu-button { display: block; }
  .menu-button[aria-expanded="true"] > span:first-child { transform: translateY(3.25px) rotate(45deg); }
  .menu-button[aria-expanded="true"] > span:nth-child(2) { transform: translateY(-3.25px) rotate(-45deg); }
  .site-nav { position: fixed; inset: 68px 0 auto; display: grid; gap: 0; max-height: 0; overflow: hidden; background: var(--canvas); border-bottom: 1px solid transparent; transition: max-height .25s, border-color .25s; }
  .site-nav.open { max-height: 380px; border-color: var(--line); }
  .site-nav a { padding: 17px 22px; border-top: 1px solid var(--line-soft); }
  .site-nav .nav-cta { margin: 12px 14px 18px; justify-content: center; }
  .hero { min-height: auto; padding-block: 62px 78px; }
  .hero-layout { grid-template-columns: 1fr; gap: 32px; }
  .signal-grid { grid-template-columns: 1fr 1fr; }
  .signal-grid div:nth-child(even) { border-left: 1px solid var(--line); }
  .signal-grid div:nth-child(n+3) { border-top: 1px solid var(--line); }
  .section { padding-block: 76px; }
  .section-intro { grid-template-columns: 1fr; gap: 28px; }
  .skill-grid { grid-template-columns: 1fr; }
  .ai-practice-grid { grid-template-columns: 1fr; }
  .skill-card { min-height: auto; }
  .featured-project { grid-template-columns: 1fr; }
  .project-diagram { min-height: 330px; }
  .case-content { grid-template-columns: 1fr; }
  .story-content { padding-left: 0; }
  .contact-grid { grid-template-columns: 1fr; }
  .contact-wechat { width: min(100%, 320px); }
  .footer-grid { grid-template-columns: 1fr; }
  .footer-actions { align-items: flex-start; }
}

@media (max-width: 560px) {
  .hero h1 { font-size: 46px; }
  .hero-lead { font-size: 17px; }
  .signal-grid strong { font-size: 15px; }
  .section-intro h2 { font-size: 39px; }
  .featured-copy, .case-content article { padding: 28px 22px; }
  .featured-copy h3 { margin-top: 42px; font-size: 39px; }
  .case-details summary { padding-inline: 22px; }
  .project-story summary { grid-template-columns: 38px 1fr; min-height: 98px; }
  .story-action { display: none; }
  .story-main strong { font-size: 22px; }
  .timeline-item { grid-template-columns: 1fr; gap: 8px; }
  .contact-foot { display: grid; gap: 10px; }
}

@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; }
}

@media print {
  :root { --canvas: white; }
  body { font-size: 10.5px; background: white; }
  .site-header, .progress, .hero-actions, .contact-actions, .site-footer, .toast, .project-diagram, .skip-link { display: none !important; }
  .js .reveal { opacity: 1 !important; transform: none !important; }
  .container { width: 100%; }
  .hero { min-height: auto; grid-template-columns: 1.15fr .85fr; padding: 0 0 24px; }
  .hero h1 { font-size: 46px; }
  .hero-lead { font-size: 13px; }
  .section { padding-block: 28px; }
  .section-intro { gap: 28px; }
  .section-intro h2 { font-size: 28px; }
  .skill-card { min-height: 0; padding: 18px; break-inside: avoid; }
  .skill-card h3 { margin-top: 20px; font-size: 20px; }
  .ai-practice-card { min-height: 0; padding: 18px; break-inside: avoid; }
  .ai-practice-card h3 { margin-top: 20px; font-size: 20px; }
  .featured-project { display: block; break-inside: avoid; }
  .featured-copy { padding: 24px; }
  details > * { display: block !important; }
  details summary { display: none !important; }
  .project-story { break-inside: avoid; }
  .project-story summary { display: grid !important; }
  .story-action { display: none; }
  .section-dark { color: var(--ink); background: white; }
  .section-dark .section-intro > p, .section-dark .eyebrow, .timeline-item span { color: var(--muted); }
  .timeline { border-color: var(--line); }
  .timeline-item { padding: 16px 0; border-color: var(--line); }
  .contact-card { padding: 28px; break-inside: avoid; }
}