:root {
  --ink: #102a2a;
  --muted: #55706d;
  --paper: #f5f2e9;
  --white: #fffdf8;
  --teal: #0d6e65;
  --lime: #c9ef81;
  --orange: #f26b3a;
  --line: rgba(16, 42, 42, .14);
  --shadow: 0 24px 70px rgba(16, 42, 42, .12);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; color: var(--ink); background: var(--paper); font-family: Inter, ui-sans-serif, system-ui, -apple-system, "Segoe UI", sans-serif; }
button, input, textarea { font: inherit; }
a { color: inherit; text-decoration: none; }

.site-header { position: sticky; z-index: 20; top: 0; display: flex; align-items: center; justify-content: space-between; min-height: 72px; padding: 0 5vw; border-bottom: 1px solid var(--line); background: rgba(245, 242, 233, .9); backdrop-filter: blur(14px); }
.brand { display: flex; align-items: center; gap: 10px; font-weight: 800; letter-spacing: -.03em; }
.brand-mark { display: block; width: 38px; height: 38px; border-radius: 9px; }
nav { display: flex; gap: 28px; font-size: .9rem; font-weight: 650; }
nav a:hover { color: var(--teal); }
.language { padding: 8px 13px; border: 1px solid var(--ink); border-radius: 999px; background: transparent; color: var(--ink); cursor: pointer; }

.section { width: min(1180px, 90vw); margin: 0 auto; padding: 110px 0; }
.hero { display: grid; min-height: calc(100vh - 72px); grid-template-columns: 1.35fr .65fr; gap: 8vw; align-items: center; }
.eyebrow { margin: 0 0 20px; color: var(--teal); font-size: .76rem; font-weight: 800; letter-spacing: .16em; }
h1 { max-width: 820px; margin: 0; font-family: Georgia, "Times New Roman", serif; font-size: clamp(3.3rem, 7vw, 6.8rem); font-weight: 500; letter-spacing: -.065em; line-height: .92; }
.lede { max-width: 670px; margin: 34px 0 0; color: var(--muted); font-size: clamp(1.05rem, 1.7vw, 1.35rem); line-height: 1.65; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 34px; }
.button { display: inline-flex; min-height: 48px; align-items: center; justify-content: center; padding: 0 20px; border: 1px solid var(--ink); border-radius: 6px; font-weight: 750; cursor: pointer; }
.primary { border-color: var(--ink); background: var(--ink); color: var(--white); }
.primary:hover { background: var(--teal); border-color: var(--teal); }
.secondary { background: transparent; }
.secondary:hover { background: var(--white); }
.micro { color: var(--muted); font-size: .82rem; }

.hero-card { padding: 28px; border-radius: 20px; background: var(--ink); color: var(--white); box-shadow: var(--shadow); transform: rotate(2deg); }
.status { display: flex; align-items: center; gap: 9px; margin-bottom: 36px; color: #cde1dc; font-size: .78rem; text-transform: uppercase; letter-spacing: .12em; }
.status i { width: 8px; height: 8px; border-radius: 50%; background: var(--lime); box-shadow: 0 0 0 5px rgba(201, 239, 129, .12); }
.flow-step { display: flex; align-items: center; gap: 18px; font-size: 1rem; }
.flow-step b { display: grid; width: 42px; height: 42px; place-items: center; border: 1px solid rgba(255,255,255,.25); border-radius: 50%; color: var(--lime); font-size: .8rem; }
.flow-line { height: 40px; margin-left: 21px; border-left: 1px dashed rgba(255,255,255,.24); }

.proof-strip { display: grid; grid-template-columns: repeat(4, 1fr); border-block: 1px solid var(--line); background: var(--white); }
.proof-strip span { padding: 24px; border-right: 1px solid var(--line); text-align: center; font-size: .82rem; font-weight: 750; }
.proof-strip span:last-child { border: 0; }
.section-heading { display: grid; grid-template-columns: .45fr 1.55fr; gap: 30px; align-items: start; margin-bottom: 56px; }
h2 { max-width: 850px; margin: 0; font-family: Georgia, "Times New Roman", serif; font-size: clamp(2.2rem, 4.7vw, 4.6rem); font-weight: 500; letter-spacing: -.05em; line-height: 1; }
.cards { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; }
.service-card { min-height: 330px; padding: 28px; border: 1px solid var(--line); border-radius: 14px; background: var(--white); display: flex; flex-direction: column; }
.service-card.featured { background: var(--teal); color: var(--white); transform: translateY(-12px); }
.card-number { color: var(--orange); font-size: .78rem; font-weight: 800; }
.service-card h3 { margin: 54px 0 16px; font-size: 1.45rem; letter-spacing: -.025em; }
.service-card p { margin: 0; color: var(--muted); line-height: 1.65; }
.service-card.featured p { color: #d4e7e3; }
.service-card strong { margin-top: auto; padding-top: 28px; font-size: .88rem; }

.demos-section { width: 100%; max-width: none; padding-inline: 5vw; background: var(--ink); color: var(--white); }
.demos-section .eyebrow { color: var(--lime); }
.demo-tabs { display: flex; gap: 8px; margin-bottom: 16px; }
.demo-tab { padding: 11px 16px; border: 1px solid rgba(255,255,255,.2); border-radius: 999px; background: transparent; color: #c3d6d3; cursor: pointer; }
.demo-tab.active { border-color: var(--lime); background: var(--lime); color: var(--ink); }
.demo-panel { display: grid; min-height: 480px; grid-template-columns: 1fr 1fr; gap: 8vw; align-items: center; scroll-margin-top: 88px; padding: 54px; border: 1px solid rgba(255,255,255,.14); border-radius: 18px; background: #143b39; }
.demo-label { color: var(--lime); font-size: .72rem; font-weight: 800; letter-spacing: .14em; }
.demo-copy h3 { margin: 18px 0; font-family: Georgia, serif; font-size: clamp(2rem, 3vw, 3.3rem); font-weight: 500; line-height: 1; }
.demo-copy p { color: #bdd0cd; line-height: 1.65; }
.question-list { display: grid; gap: 8px; margin-top: 25px; }
.question-list button { padding: 12px 15px; border: 1px solid rgba(255,255,255,.2); border-radius: 7px; background: rgba(255,255,255,.04); color: var(--white); text-align: left; cursor: pointer; }
.question-list button:hover { border-color: var(--lime); }
.chat-window { min-height: 310px; padding: 22px; border-radius: 14px; background: var(--white); color: var(--ink); box-shadow: var(--shadow); }
.chat-top { display: flex; align-items: center; gap: 12px; padding-bottom: 18px; border-bottom: 1px solid var(--line); }
.chat-top > span { display: grid; width: 42px; height: 42px; place-items: center; border-radius: 50%; background: var(--orange); color: var(--white); font-weight: 800; }
.chat-top small { display: block; margin-top: 3px; color: var(--muted); }
.message { margin: 28px 0; padding: 16px; border-radius: 5px 14px 14px 14px; background: #e7f3d2; line-height: 1.55; }
.guardrail { color: var(--muted); font-size: .72rem; text-align: center; }
.data-output { display: grid; grid-template-columns: repeat(3, 1fr); gap: 10px; }
.data-output > div { padding: 18px; border-radius: 10px; background: var(--white); color: var(--ink); }
.data-output small { display: block; min-height: 30px; color: var(--muted); font-size: .66rem; font-weight: 800; }
.data-output strong { font-size: 1.7rem; }
.data-output pre { grid-column: 1 / -1; min-height: 170px; overflow: auto; padding: 18px; border-radius: 10px; background: #082624; color: #cce9e4; white-space: pre-wrap; }
.comparison { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; }
.comparison > div { min-height: 260px; padding: 25px; border: 1px solid rgba(255,255,255,.16); border-radius: 12px; color: #abc0bd; }
.comparison .after { border-color: var(--lime); background: var(--white); color: var(--ink); transform: translateY(-12px); }
.comparison span { font-size: .67rem; font-weight: 850; letter-spacing: .15em; }
.comparison h4 { margin-top: 70px; font-size: 1.35rem; }

.process ol { display: grid; grid-template-columns: repeat(4, 1fr); margin: 0; padding: 0; border-top: 1px solid var(--line); list-style: none; }
.process li { padding: 26px 22px 26px 0; border-right: 1px solid var(--line); }
.process li + li { padding-left: 22px; }
.process li > span { color: var(--orange); font-size: .72rem; font-weight: 850; }
.process li b { display: block; margin-top: 42px; }
.process li p { color: var(--muted); font-size: .9rem; line-height: 1.5; }
.case-study { border-top: 1px solid var(--line); }
.case-layout { display: grid; grid-template-columns: 1.2fr .8fr; gap: 5vw; align-items: stretch; }
.case-story, .case-results { padding: 34px; border-radius: 16px; }
.case-story { background: var(--white); box-shadow: var(--shadow); }
.case-story h3 { margin: 22px 0 14px; font-size: 1.8rem; }
.case-story p { color: var(--muted); line-height: 1.7; }
.case-badge { display: inline-block; padding: 7px 10px; border-radius: 999px; background: var(--orange); font-size: .7rem; font-weight: 800; letter-spacing: .06em; }
.case-note { padding-top: 18px; border-top: 1px solid var(--line); font-size: .82rem; }
.case-results { display: grid; gap: 14px; background: var(--teal); color: var(--white); }
.case-results div { display: flex; gap: 8px; align-items: center; padding-bottom: 14px; border-bottom: 1px solid rgba(255,255,255,.18); }
.case-results strong { flex: 0 0 26px; color: var(--lime); font-size: 2.2rem; }
.case-results span { line-height: 1.4; }
.case-results .button { align-self: end; background: var(--lime); color: var(--ink); }
.contact { display: grid; grid-template-columns: 1fr 1fr; gap: 9vw; margin-bottom: 100px; padding: 70px; border-radius: 18px; background: var(--orange); }
.contact h2 { font-size: clamp(2.2rem, 4vw, 4rem); }
.contact > div > p:last-child { line-height: 1.6; }
form { display: grid; gap: 16px; padding: 25px; border-radius: 12px; background: var(--white); }
label span { display: block; margin-bottom: 6px; font-size: .76rem; font-weight: 800; }
input, textarea { width: 100%; padding: 12px; border: 1px solid var(--line); border-radius: 6px; background: #faf9f4; color: var(--ink); }
input:focus, textarea:focus { outline: 2px solid var(--teal); border-color: transparent; }
.form-note { margin: 0; color: var(--muted); font-size: .72rem; line-height: 1.4; }
.wechat-card { display: grid; grid-template-columns: minmax(0, .8fr) minmax(190px, 1.2fr); gap: 22px; align-items: center; padding: 24px; border-radius: 14px; background: var(--white); box-shadow: var(--shadow); }
.wechat-card img { display: block; width: 100%; max-height: 410px; object-fit: contain; border-radius: 8px; }
.wechat-card h3 { margin: 15px 0 10px; font-size: 1.35rem; line-height: 1.25; }
.wechat-card p { color: var(--muted); font-size: .86rem; line-height: 1.55; }
.wechat-card a { display: inline-block; margin-top: 12px; color: var(--teal); font-size: .78rem; font-weight: 750; overflow-wrap: anywhere; }
footer { display: flex; justify-content: space-between; padding: 28px 5vw; border-top: 1px solid var(--line); color: var(--muted); font-size: .78rem; }

@media (max-width: 850px) {
  nav { display: none; }
  .section { padding: 76px 0; }
  .hero { grid-template-columns: 1fr; padding-top: 60px; }
  .hero-card { transform: none; }
  .proof-strip { grid-template-columns: 1fr 1fr; }
  .proof-strip span:nth-child(2) { border-right: 0; }
  .section-heading, .demo-panel, .case-layout, .contact { grid-template-columns: 1fr; }
  .cards { grid-template-columns: 1fr; }
  .service-card.featured { transform: none; }
  .demo-panel { padding: 26px; }
  .demos-section .section-heading { width: 100%; }
  .demos-section .section-heading .eyebrow { text-align: center; }
  .demos-section .section-heading h2 { width: 100%; margin-inline: auto; text-align: center; }
  .process ol { grid-template-columns: 1fr 1fr; }
  .contact { width: 90vw; padding: 30px; }
  .wechat-card { grid-template-columns: 1fr; }
  .wechat-card img { width: min(100%, 320px); margin: 0 auto; }
}

@media (max-width: 520px) {
  h1 { max-width: 100%; font-size: 2.85rem; overflow-wrap: anywhere; }
  .hero-copy { min-width: 0; }
  .hero-actions { display: grid; grid-template-columns: 1fr; }
  .hero-actions .button { width: 100%; }
  .hero-card { min-width: 0; padding: 22px; }
  .flow-step { gap: 12px; font-size: .9rem; }
  .proof-strip, .process ol, .comparison { grid-template-columns: 1fr; }
  .proof-strip span { border-right: 0; border-bottom: 1px solid var(--line); }
  .process li, .process li + li { padding: 28px 12px; border-right: 0; border-bottom: 1px solid var(--line); text-align: center; }
  .process li:last-child { border-bottom: 0; }
  .process li b { margin-top: 16px; }
  .demo-tabs { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); width: 100%; overflow: visible; }
  .demo-tab { min-width: 0; padding: 10px 5px; font-size: .8rem; white-space: nowrap; }
  .data-output { grid-template-columns: 1fr; }
  .data-output pre { grid-column: 1; }
  footer { flex-direction: column; gap: 8px; }
}