:root {
  --bg: #050c1e;
  --bg-2: #0a1730;
  --bg-alt: #081120;
  --card: rgba(255, 255, 255, 0.04);
  --card-bd: rgba(120, 180, 255, 0.14);
  --text: #e8eefb;
  --dim: #9fb2d4;
  --blue: #2f7df6;
  --blue-2: #4fa8f5;
  --cyan: #00d8f0;
  --cyan-2: #26c6da;
  --gold: #fbbf24;
  --purple: #a78bfa;
  --radius: 16px;
  --maxw: 1180px;
  --font: "PingFang SC", "Microsoft YaHei", "Source Han Sans SC", "Noto Sans CJK SC", system-ui, -apple-system, sans-serif;
}

* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}
a { color: inherit; text-decoration: none; }
small { font-size: 0.62em; opacity: 0.8; font-weight: 400; }

/* ===== Nav ===== */
.nav {
  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
  backdrop-filter: blur(14px);
  background: rgba(5, 12, 30, 0.72);
  border-bottom: 1px solid rgba(120, 180, 255, 0.08);
  transition: background 0.3s;
}
.nav__inner {
  max-width: 1360px; margin: 0 auto; padding: 14px 24px;
  display: flex; align-items: center; gap: 16px;
}
.brand { display: flex; align-items: center; gap: 12px; font-weight: 800; font-size: 19px; }
.brand__mark {
  width: 38px; height: 38px; border-radius: 10px; display: grid; place-items: center;
  background: linear-gradient(135deg, var(--blue), var(--cyan));
  color: #04101e; font-weight: 900; font-size: 22px;
  box-shadow: 0 6px 18px rgba(47, 125, 246, 0.45);
}
.brand__text small { display: block; letter-spacing: 1px; color: var(--cyan); }
.nav__links { display: flex; gap: 15px; margin-left: auto; font-size: 13.5px; }
.nav__links a { color: var(--dim); transition: color 0.2s; position: relative; white-space: nowrap; }
.nav__links a:hover { color: var(--cyan); }
.nav__cta {
  background: linear-gradient(135deg, var(--blue), var(--cyan));
  color: #04101e !important; font-weight: 700; padding: 9px 18px; border-radius: 999px;
  box-shadow: 0 6px 18px rgba(47, 125, 246, 0.4);
}
.nav__cta:hover { filter: brightness(1.08); }
.nav__toggle { display: none; background: none; border: 0; color: var(--text); font-size: 26px; cursor: pointer; margin-left: auto; }

/* ===== Hero ===== */
.hero { position: relative; min-height: 100vh; display: flex; align-items: center; overflow: hidden; }
.hero__bg {
  position: absolute; inset: 0;
  background:
    radial-gradient(900px 500px at 75% 15%, rgba(0, 216, 240, 0.18), transparent 60%),
    radial-gradient(800px 500px at 10% 80%, rgba(47, 125, 246, 0.20), transparent 60%),
    linear-gradient(160deg, #061127, #040a18 70%);
}
.hero__bg::after {
  content: ""; position: absolute; inset: 0; opacity: 0.5;
  background-image:
    linear-gradient(rgba(120, 180, 255, 0.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(120, 180, 255, 0.05) 1px, transparent 1px);
  background-size: 44px 44px;
  mask-image: radial-gradient(circle at 50% 40%, #000 30%, transparent 75%);
}
.hero__inner { position: relative; max-width: var(--maxw); margin: 0 auto; padding: 120px 24px 80px; width: 100%; }
.hero__badge {
  display: inline-block; padding: 8px 16px; border-radius: 999px; font-size: 13.5px;
  background: rgba(0, 216, 240, 0.1); border: 1px solid rgba(0, 216, 240, 0.35); color: var(--cyan);
  margin-bottom: 26px; letter-spacing: 0.5px;
}
.hero__title { font-size: clamp(30px, 5vw, 56px); line-height: 1.2; font-weight: 900; letter-spacing: 0.5px; }
.hero__title .hl { background: linear-gradient(120deg, var(--cyan), var(--blue-2)); -webkit-background-clip: text; background-clip: text; color: transparent; }
.hero__sub { margin: 24px 0 28px; max-width: 760px; color: var(--dim); font-size: clamp(15px, 1.6vw, 18px); }
.hero__actions { display: flex; gap: 16px; flex-wrap: wrap; }
.btn { padding: 13px 26px; border-radius: 999px; font-weight: 700; font-size: 15px; transition: transform 0.2s, filter 0.2s; }
.btn:hover { transform: translateY(-2px); }
.btn--primary { background: linear-gradient(135deg, var(--blue), var(--cyan)); color: #04101e; box-shadow: 0 10px 28px rgba(47, 125, 246, 0.45); }
.btn--ghost { border: 1px solid rgba(120, 180, 255, 0.4); color: var(--text); }
.btn--ghost:hover { border-color: var(--cyan); color: var(--cyan); }
.hero__stats { display: grid; grid-template-columns: repeat(4, 1fr); gap: 18px; margin-top: 48px; max-width: 880px; }
.stat { background: var(--card); border: 1px solid var(--card-bd); border-radius: var(--radius); padding: 18px 16px; }
.stat b { display: block; font-size: 30px; font-weight: 900; background: linear-gradient(120deg, var(--cyan), var(--blue-2)); -webkit-background-clip: text; background-clip: text; color: transparent; }
.stat span { font-size: 13px; color: var(--dim); }
.hero__scroll { position: absolute; bottom: 22px; left: 50%; transform: translateX(-50%); color: var(--dim); font-size: 13px; animation: bob 2s infinite; }
@keyframes bob { 0%,100%{ transform: translate(-50%,0);} 50%{ transform: translate(-50%,8px);} }

/* ===== Section ===== */
.section { max-width: var(--maxw); margin: 0 auto; padding: 84px 24px; }
.section--alt { max-width: none; background: linear-gradient(180deg, rgba(8,17,32,0.6), rgba(5,12,30,0.2)); border-top: 1px solid rgba(120,180,255,0.06); border-bottom: 1px solid rgba(120,180,255,0.06); }
.section--alt > * { max-width: var(--maxw); margin-left: auto; margin-right: auto; }
.section--dark { max-width: none; background: linear-gradient(180deg, #061325, #040a18); }
.section--dark > * { max-width: var(--maxw); margin-left: auto; margin-right: auto; }
.section__head { text-align: center; margin-bottom: 42px; }
.kicker { font-size: 13px; letter-spacing: 3px; color: var(--cyan); font-weight: 700; }
.section__head h2 { font-size: clamp(24px, 3.4vw, 38px); margin: 14px 0 18px; font-weight: 900; }
.lead { max-width: 820px; margin: 0 auto; color: var(--dim); font-size: clamp(15px, 1.6vw, 17.5px); }
.lead strong { color: var(--text); }

/* ===== FDE flow ===== */
.fde-flow { display: flex; align-items: stretch; justify-content: center; gap: 14px; flex-wrap: wrap; margin-bottom: 46px; }
.fde-node { flex: 1 1 240px; min-width: 220px; background: var(--card); border: 1px solid var(--card-bd); border-radius: var(--radius); padding: 26px 20px; text-align: center; }
.fde-node__icon { font-size: 40px; margin-bottom: 10px; }
.fde-node h4 { font-size: 18px; margin-bottom: 8px; }
.fde-node p { font-size: 13.5px; color: var(--dim); }
.fde-node--up { border-color: rgba(167,139,250,0.4); }
.fde-node--mid { border-color: rgba(0,216,240,0.5); background: rgba(0,216,240,0.06); }
.fde-node--down { border-color: rgba(47,125,246,0.4); }
.fde-arrow { display: flex; align-items: center; justify-content: center; color: var(--cyan); font-weight: 700; font-size: 13px; padding: 8px 4px; white-space: nowrap; }

.fde-grid, .tech-grid, .eco-grid, .cases, .products, .engines, .steps { display: grid; gap: 20px; }
.fde-grid { grid-template-columns: repeat(4, 1fr); margin-top: 20px; }
.card { background: var(--card); border: 1px solid var(--card-bd); border-radius: var(--radius); padding: 24px 22px; transition: transform 0.25s, border-color 0.25s; }
.card:hover { transform: translateY(-4px); border-color: rgba(0,216,240,0.45); }
.card h4 { font-size: 17px; margin-bottom: 10px; }
.card p { color: var(--dim); font-size: 14.5px; }

/* ===== Engines ===== */
.engines { grid-template-columns: repeat(3, 1fr); }
.engine { border-radius: var(--radius); padding: 30px 26px; border: 1px solid var(--card-bd); background: var(--card); position: relative; overflow: hidden; }
.engine::before { content: ""; position: absolute; top: 0; left: 0; right: 0; height: 4px; }
.engine--deliver::before { background: linear-gradient(90deg, var(--blue), var(--cyan)); }
.engine--platform::before { background: linear-gradient(90deg, var(--cyan-2), var(--purple)); }
.engine--eco::before { background: linear-gradient(90deg, var(--gold), var(--blue-2)); }
.engine__tag { font-size: 12.5px; color: var(--cyan); font-weight: 700; letter-spacing: 1px; margin-bottom: 10px; }
a.engine { color: inherit; cursor: pointer; }
a.engine:hover { color: inherit; }
.engine h3 { font-size: 22px; margin-bottom: 12px; }
.engine p { color: var(--dim); font-size: 14.5px; margin-bottom: 14px; }
.engine ul { list-style: none; display: grid; gap: 8px; }
.engine li { font-size: 13.5px; color: var(--text); padding-left: 18px; position: relative; }
.engine li::before { content: "▸"; position: absolute; left: 0; color: var(--cyan); }
.position-note { margin-top: 28px; padding: 22px 24px; border-radius: var(--radius); background: rgba(0,216,240,0.08); border: 1px solid rgba(0,216,240,0.3); font-size: 16px; }
.position-note strong { color: var(--cyan); }

/* ===== Products ===== */
.products { grid-template-columns: repeat(2, 1fr); }
.product { background: var(--card); border: 1px solid var(--card-bd); border-radius: var(--radius); padding: 30px 28px; position: relative; transition: transform 0.25s, border-color 0.25s; }
.product:hover { transform: translateY(-4px); border-color: rgba(0,216,240,0.5); }
.product--platform { grid-column: 1 / -1; background: linear-gradient(135deg, rgba(0,216,240,0.08), rgba(167,139,250,0.06)); border-color: rgba(0,216,240,0.35); }
.product--wide { grid-column: 1 / -1; }
.product__no { position: absolute; top: 20px; right: 24px; font-size: 30px; font-weight: 900; color: rgba(120,180,255,0.18); }
.product h3 { font-size: 21px; margin-bottom: 8px; }
.product__pill { display: inline-block; font-size: 12.5px; color: var(--cyan); border: 1px solid rgba(0,216,240,0.35); border-radius: 999px; padding: 3px 12px; margin-bottom: 14px; }
.product p { color: var(--dim); font-size: 14.5px; margin-bottom: 10px; }
.product p strong { color: var(--text); }
.product__point { color: var(--text) !important; font-size: 13.5px !important; }
.product__note { font-size: 12.5px !important; color: var(--gold) !important; opacity: 0.85; }

/* ===== Tech ===== */
.tech-grid { grid-template-columns: repeat(3, 1fr); }

/* ===== Steps ===== */
.steps { grid-template-columns: repeat(4, 1fr); }
.step { background: var(--card); border: 1px solid var(--card-bd); border-radius: var(--radius); padding: 28px 22px; position: relative; }
.step__no { font-size: 40px; font-weight: 900; background: linear-gradient(120deg, var(--cyan), var(--blue-2)); -webkit-background-clip: text; background-clip: text; color: transparent; margin-bottom: 8px; }
.step h4 { font-size: 17px; margin-bottom: 8px; }
.step p { color: var(--dim); font-size: 14px; }

/* ===== Cases ===== */
.cases { grid-template-columns: repeat(3, 1fr); }
.case { background: var(--card); border: 1px solid var(--card-bd); border-radius: var(--radius); padding: 26px 24px; transition: transform 0.25s, border-color 0.25s; }
.case:hover { transform: translateY(-4px); border-color: rgba(0,216,240,0.5); }
.case__tag { display: inline-block; font-size: 12px; color: var(--gold); border: 1px solid rgba(251,191,36,0.4); border-radius: 999px; padding: 2px 12px; margin-bottom: 12px; }
.case h3 { font-size: 18px; margin-bottom: 10px; line-height: 1.4; }
.case p { color: var(--dim); font-size: 14px; }
a.case { display: block; color: inherit; cursor: pointer; }
a.case:hover { color: inherit; }
.case__more { display: inline-flex; align-items: center; gap: 6px; margin-top: 14px; font-size: 13.5px; font-weight: 600; color: var(--cyan); }
a.case:hover .case__more { gap: 10px; }

/* ===== Eco ===== */
.eco-grid { grid-template-columns: repeat(4, 1fr); }

/* ===== About / Contact ===== */
.about-grid { display: grid; grid-template-columns: 1.2fr 1fr; gap: 36px; }
.about-col h4 { color: var(--cyan); font-size: 16px; margin: 18px 0 6px; }
.about-col p { color: var(--dim); font-size: 15px; }
.about-col--contact { background: var(--card); border: 1px solid var(--card-bd); border-radius: var(--radius); padding: 30px 28px; }
.contact-list { list-style: none; display: grid; gap: 14px; margin-top: 6px; }
.contact-list li { font-size: 14.5px; color: var(--text); display: flex; gap: 10px; align-items: baseline; }
.contact-list li span { color: var(--cyan); min-width: 54px; font-weight: 700; }
.contact-note { margin-top: 18px; font-size: 12.5px; color: var(--gold); opacity: 0.85; }

/* ===== Footer ===== */
.footer { border-top: 1px solid rgba(120,180,255,0.08); background: #040a18; }
.footer__inner { max-width: var(--maxw); margin: 0 auto; padding: 26px 24px; display: flex; justify-content: space-between; gap: 16px; flex-wrap: wrap; color: var(--dim); font-size: 13px; }
.footer__inner .icp a { color: inherit; text-decoration: none; border-bottom: 1px dashed currentColor; opacity: .85; }
.footer__inner .icp a:hover { opacity: 1; }

/* ===== Reveal animation ===== */
.reveal { opacity: 0; transform: translateY(22px); transition: opacity 0.6s ease, transform 0.6s ease; }
.reveal.in { opacity: 1; transform: none; }

/* ===== Responsive ===== */
@media (max-width: 980px) {
  .fde-grid, .tech-grid, .eco-grid, .cases, .steps { grid-template-columns: repeat(2, 1fr); }
  .engines, .products { grid-template-columns: 1fr; }
  .about-grid { grid-template-columns: 1fr; }
}
@media (max-width: 1150px) {
  .nav__links { display: none; position: absolute; top: 64px; left: 0; right: 0; flex-direction: column; background: rgba(5,12,30,0.97); padding: 18px 24px; gap: 14px; border-bottom: 1px solid rgba(120,180,255,0.12); }
  .nav__links.open { display: flex; }
  .nav__toggle { display: block; }
  .nav__cta { display: none; }
}
@media (max-width: 720px) {
  .hero__stats { grid-template-columns: repeat(2, 1fr); }
  .fde-grid, .tech-grid, .eco-grid, .cases, .steps { grid-template-columns: 1fr; }
  .fde-arrow { transform: rotate(90deg); }
  .section { padding: 64px 18px; }
  .hero__inner { padding-top: 100px; }
}

/* ===== 首屏价值标签 ===== */
.hero__tags { display: flex; flex-wrap: wrap; gap: 12px; margin: 0 0 30px; justify-content: flex-start; }
.hero__tag { font-size: 13.5px; color: var(--cyan); background: rgba(0,216,240,0.08); border: 1px solid rgba(0,216,240,0.28); border-radius: 999px; padding: 8px 16px; }

/* ===== 数据指标收益说明 ===== */
.hero__stats-cap { margin-top: 16px; font-size: 13px; color: var(--gold); opacity: 0.9; text-align: center; }

/* ===== 术语人话翻译 ===== */
.glossary { margin-top: 36px; background: rgba(0,216,240,0.05); border: 1px solid rgba(0,216,240,0.2); border-radius: var(--radius); padding: 24px 26px; }
.glossary h4 { color: var(--cyan); font-size: 16px; margin-bottom: 12px; }
.glossary ul { list-style: none; display: grid; gap: 12px; }
.glossary li { font-size: 14.5px; color: var(--dim); line-height: 1.7; }
.glossary li b { color: var(--text); }

/* ===== SVG 图 ===== */
.fde-diagram, .method-diagram { margin: 26px auto 0; max-width: 860px; }
.fde-diagram svg, .method-diagram svg { width: 100%; height: auto; }
.diagram-cap { margin-top: 12px; text-align: center; font-size: 13px; color: var(--dim); }

/* ===== 卡片一句话价值 slogan ===== */
.slogan { display: inline-block; margin: 6px 0 10px; font-size: 13.5px; font-weight: 700; color: var(--gold); background: rgba(255,212,121,0.1); border-left: 3px solid var(--gold); padding: 6px 12px; border-radius: 0 8px 8px 0; }

/* ===== 案例量化成果 ===== */
.case__metric { margin-top: 12px; font-size: 13px; color: var(--cyan); font-weight: 700; background: rgba(0,216,240,0.07); border-radius: 8px; padding: 8px 12px; }

/* ===== 固定侧边锚点导航 ===== */
.side-nav { position: fixed; right: 16px; top: 50%; transform: translateY(-50%); z-index: 40; display: flex; flex-direction: column; gap: 11px; }
.side-nav a { width: 10px; height: 10px; border-radius: 50%; background: rgba(120,180,255,0.25); position: relative; transition: all 0.2s; }
.side-nav a:hover { background: var(--cyan); transform: scale(1.3); }
.side-nav a.active { background: var(--cyan); box-shadow: 0 0 0 4px rgba(0,216,240,0.18); }
.side-nav a::after { content: attr(data-label); position: absolute; right: 18px; top: 50%; transform: translateY(-50%); white-space: nowrap; font-size: 12px; color: var(--text); background: rgba(5,12,30,0.95); border: 1px solid rgba(120,180,255,0.18); padding: 3px 8px; border-radius: 6px; opacity: 0; pointer-events: none; transition: opacity 0.2s; }
.side-nav a:hover::after { opacity: 1; }

@media (max-width: 980px) {
  .side-nav { display: none; }
}

/* ===== P1 转化升级：客户类型 / 留资 / 卡片行动区 ===== */
.cta-row { margin-top: 26px; display: flex; gap: 18px; flex-wrap: wrap; align-items: center; }

.start-types { display: flex; flex-wrap: wrap; align-items: center; justify-content: center; gap: 12px; max-width: 880px; margin: 6px auto 34px; }
.start-types__label { color: var(--cyan); font-weight: 700; font-size: 14px; }
.chip {
  font-size: 13.5px; color: var(--text); border: 1px solid rgba(120,180,255,0.3);
  border-radius: 999px; padding: 8px 18px; cursor: pointer; transition: all 0.2s;
}
.chip:hover { border-color: var(--cyan); color: var(--cyan); background: rgba(0,216,240,0.08); }

.engine__actions { display: flex; align-items: center; gap: 16px; flex-wrap: wrap; margin-top: 18px; }
.btn--sm { padding: 9px 18px; font-size: 13.5px; }

.lead-form-wrap {
  max-width: 720px; margin: 44px auto 0; background: var(--card);
  border: 1px solid var(--card-bd); border-radius: var(--radius); padding: 30px 28px;
}
.lead-form__title { color: var(--cyan); font-size: 17px; margin-bottom: 16px; text-align: center; }
.lead-form { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }
.lead-form input {
  background: rgba(255,255,255,0.05); border: 1px solid var(--card-bd); border-radius: 10px;
  padding: 12px 14px; color: var(--text); font-size: 14.5px; font-family: inherit;
}
.lead-form input::placeholder { color: var(--dim); }
.lead-form input:focus { outline: none; border-color: var(--cyan); }
.lead-form input[name="phone"] { grid-column: 1 / -1; }
.lead-form button { grid-column: 1 / -1; margin-top: 4px; }
.lead-form__hint { margin-top: 14px; font-size: 12.5px; color: var(--dim); text-align: center; }

@media (max-width: 720px) {
  .lead-form { grid-template-columns: 1fr; }
  .start-types { margin-bottom: 28px; }
}

/* ===== 企业 AI 原生转型业务线 ===== */
.section__subhead {
  margin: 40px 0 18px; text-align: center;
  font-size: 15px; font-weight: 700; color: var(--gold); letter-spacing: 0.5px;
}
.section__subhead::before, .section__subhead::after { content: "—"; margin: 0 10px; opacity: 0.5; }
.step h4 small { display: inline-block; margin-left: 6px; font-size: 12px; font-weight: 600; color: var(--cyan); opacity: 1; letter-spacing: 0; }

/* 开始合作：四条业务线 2×2，避免 3 列缺块 */
.engines--2x2 { grid-template-columns: repeat(2, 1fr); }
@media (max-width: 980px) {
  .engines--2x2 { grid-template-columns: 1fr; }
}