:root {
  --blue:#2d59ad;
  --blue-2:#3768bf;
  --blue-deep:#183d83;
  --teal:#11b8ad;
  --green:#92c83e;
  --ink:#152033;
  --muted:#687386;
  --line:#e7edf6;
  --soft:#f4f7fb;
  --white:#fff;
  --radius:22px;
  --shadow:0 20px 55px rgba(24,61,131,.10);
  --container:1220px;
}

*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;font-family:"PingFang SC","Microsoft YaHei",system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;color:var(--ink);background:#fff;line-height:1.72;-webkit-font-smoothing:antialiased}
img{max-width:100%;display:block}
a{color:inherit;text-decoration:none}
button{font:inherit}
.container{width:min(var(--container),calc(100% - 48px));margin-inline:auto}
.section{padding:108px 0}
.soft{background:var(--soft)}
.eyebrow{margin:0 0 8px;color:var(--blue);font-size:13px;font-weight:800;letter-spacing:.18em}
.eyebrow.light{color:#cfe0ff}
.section-heading{text-align:center;max-width:800px;margin:0 auto 58px}
.section-heading h2{font-size:42px;line-height:1.25;margin:0 0 16px;font-weight:720;letter-spacing:-.04em}
.section-heading p:last-child{margin:0;color:var(--muted);font-size:17px}

.site-header{height:88px;background:rgba(255,255,255,.94);position:sticky;top:0;z-index:50;border-bottom:1px solid rgba(231,237,246,.85);backdrop-filter:blur(18px);-webkit-backdrop-filter:blur(18px)}
.nav-shell{height:100%;width:min(1320px,calc(100% - 48px));margin:auto;display:flex;align-items:center;justify-content:space-between;gap:32px}
.brand img{width:244px;height:auto}
.main-nav{display:flex;align-items:center;gap:38px;font-size:15px;font-weight:600;color:#2e3747}
.main-nav a{position:relative;padding:31px 0 29px;white-space:nowrap}
.main-nav a::after{content:"";position:absolute;left:0;right:100%;bottom:19px;height:2px;background:linear-gradient(90deg,var(--teal),var(--blue));transition:.25s;border-radius:2px}
.main-nav a:hover,.main-nav a.active{color:var(--blue)}
.main-nav a:hover::after,.main-nav a.active::after{right:0}
.nav-toggle{display:none;width:42px;height:42px;border:0;background:transparent;padding:8px;cursor:pointer}
.nav-toggle span{display:block;height:2px;background:#23334c;margin:6px 0;border-radius:4px;transition:.2s}

.hero{position:relative;height:min(720px,calc(100vh - 88px));min-height:540px;overflow:hidden;background:#0d1c16}
.hero-video{width:100%;height:100%;object-fit:cover;display:block}
.hero-shade{position:absolute;inset:0;background:linear-gradient(90deg,rgba(7,20,19,.62) 0%,rgba(7,20,19,.25) 48%,rgba(7,20,19,.08) 100%)}
.hero-copy{position:absolute;left:50%;top:50%;transform:translate(-50%,-48%);color:white}
.hero-copy h1{font-size:58px;line-height:1.13;max-width:760px;margin:0 0 22px;font-weight:760;letter-spacing:-.05em;text-shadow:0 2px 24px rgba(0,0,0,.16)}
.hero-copy>p:not(.eyebrow){max-width:680px;margin:0;font-size:19px;color:rgba(255,255,255,.88)}
.hero-actions{display:flex;gap:14px;margin-top:34px}
.btn{display:inline-flex;align-items:center;justify-content:center;min-height:50px;padding:0 25px;border-radius:999px;font-weight:700;font-size:15px;transition:.25s;border:1px solid transparent}
.btn-primary{background:linear-gradient(135deg,var(--teal),#148cc9);color:#fff;box-shadow:0 12px 30px rgba(17,184,173,.27)}
.btn-primary:hover{transform:translateY(-2px);box-shadow:0 18px 35px rgba(17,184,173,.34)}
.btn-ghost{border-color:rgba(255,255,255,.55);color:#fff;background:rgba(255,255,255,.08);backdrop-filter:blur(8px)}
.btn-ghost:hover{background:rgba(255,255,255,.18)}
.btn-light{background:#fff;color:var(--blue);margin-top:20px}
.sound-toggle{position:absolute;right:28px;bottom:26px;border:1px solid rgba(255,255,255,.25);background:rgba(0,0,0,.28);color:#fff;width:48px;height:48px;border-radius:50%;cursor:pointer;backdrop-filter:blur(8px)}

.feature-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:28px}
.feature-card{background:#fff;border:1px solid #e9eff8;border-radius:var(--radius);overflow:hidden;box-shadow:0 12px 40px rgba(31,70,133,.06);transition:.3s}
.feature-card:hover{transform:translateY(-7px);box-shadow:var(--shadow);border-color:#d7e4f8}
.feature-media{height:224px;display:flex;align-items:center;justify-content:center;background:linear-gradient(180deg,#f9fbfe,#f1f6fd);overflow:hidden}
.feature-media img{width:100%;height:100%;object-fit:cover}
.feature-body{position:relative;padding:26px 28px 30px}
.feature-index{position:absolute;right:24px;top:22px;font-size:12px;font-weight:800;color:#b6c9e8;letter-spacing:.1em}
.feature-body h3{margin:0 0 12px;font-size:22px;color:#1b2b44}
.feature-body p{margin:0;color:var(--muted);font-size:15px}

.rescue-system{position:relative;max-width:1050px;margin:auto;padding:72px 58px 46px;border-radius:36px;background:
radial-gradient(circle at 50% 36%,rgba(53,97,185,.09) 0 18%,transparent 18.5%),
radial-gradient(circle at 50% 36%,rgba(53,97,185,.06) 0 36%,transparent 36.5%),
linear-gradient(180deg,#f8faff,#f0f5ff);border:1px solid #dfe9f8;overflow:hidden}
.rescue-top{width:170px;height:116px;border-radius:28px;background:linear-gradient(145deg,var(--blue-2),var(--blue));color:#fff;display:flex;flex-direction:column;justify-content:center;align-items:center;margin:-10px auto 54px;font-size:20px;box-shadow:0 18px 30px rgba(45,89,173,.18)}
.rescue-top strong{font-size:27px;line-height:1.15}
.rescue-line{height:1px;background:repeating-linear-gradient(90deg,var(--blue) 0 5px,transparent 5px 9px);width:78%;position:absolute;top:208px;left:11%}
.device-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:28px;position:relative;z-index:2}
.device-column{text-align:center}
.device-pill{display:inline-flex;min-width:122px;min-height:44px;align-items:center;justify-content:center;background:var(--blue);color:#fff;padding:0 20px;border-radius:999px;font-size:17px;box-shadow:0 8px 20px rgba(45,89,173,.16)}
.device-orb{width:142px;height:142px;border-radius:50%;background:linear-gradient(145deg,#3769bd,#244f9d);color:#fff;margin:30px auto 0;display:flex;align-items:center;justify-content:center;font-size:17px;font-weight:650;line-height:1.45;box-shadow:0 16px 34px rgba(45,89,173,.18)}
.service-panel{margin-top:52px;border:1px dashed #5f84c7;border-radius:22px;padding:24px;display:grid;grid-template-columns:repeat(4,1fr);gap:12px;background:rgba(255,255,255,.62)}
.service-panel span{min-height:42px;border-radius:8px;background:linear-gradient(135deg,#2b59ab,#4774c6);display:flex;align-items:center;justify-content:center;color:#fff;font-size:14px;font-weight:650}

.roles-layout{display:grid;grid-template-columns:1fr 430px 1fr;gap:34px;align-items:center}
.role-notes{display:grid;gap:20px}
.role-notes article{background:#fff;border:1px solid #e7edf7;border-radius:18px;padding:22px 22px 20px;box-shadow:0 10px 28px rgba(37,76,140,.055)}
.role-notes h3{margin:0 0 7px;color:var(--blue);font-size:18px}
.role-notes p{margin:0;color:var(--muted);font-size:14px}
.role-wheel{width:390px;height:390px;border-radius:50%;margin:auto;position:relative;background:conic-gradient(from -32deg,var(--blue) 0 64deg,#ffd100 64deg 132deg,var(--blue) 132deg 205deg,#284f9b 205deg 278deg,#f0b900 278deg 360deg);box-shadow:0 25px 70px rgba(45,89,173,.13)}
.role-wheel::after{content:"";position:absolute;inset:78px;background:var(--soft);border-radius:50%;box-shadow:inset 0 0 0 1px rgba(45,89,173,.10)}
.wheel-center{position:absolute;inset:0;display:flex;align-items:center;justify-content:center;text-align:center;z-index:3;color:var(--blue);font-size:25px;font-weight:800;line-height:1.25}
.wheel-label{position:absolute;z-index:4;color:#fff;font-weight:800;font-size:15px;text-shadow:0 1px 1px rgba(0,0,0,.06);white-space:nowrap}
.wheel-label.top{top:32px;left:50%;transform:translateX(-50%)}
.wheel-label.right{right:7px;top:49%;transform:translateY(-50%);color:#174fa0}
.wheel-label.bottom-right{right:60px;bottom:54px}
.wheel-label.bottom-left{left:50px;bottom:54px}
.wheel-label.left{left:12px;top:42%;transform:translateY(-50%);color:#174fa0}

.tech-list{border-top:1px solid var(--line)}
.tech-row{min-height:180px;display:grid;grid-template-columns:90px 280px 1fr;align-items:center;border-bottom:1px solid var(--line);gap:28px;padding:28px 20px;transition:.25s}
.tech-row:hover{background:#f8fafe}
.tech-letter{font-size:68px;font-weight:300;color:#d9e3f2;line-height:1}
.tech-title h3{margin:0;color:#0678bf;font-size:25px;line-height:1.35}
.tech-row p{margin:0;color:#596477;font-size:16px}

.future-section{background:var(--blue);padding:88px 0 94px;color:#fff;overflow:hidden}
.future-grid{display:grid;grid-template-columns:1fr 1fr;gap:56px;align-items:center}
.future-map img{width:100%;max-width:570px;margin:auto;mix-blend-mode:screen}
.future-copy h2{font-size:43px;line-height:1.2;margin:0 0 22px;letter-spacing:-.035em}
.future-copy p:not(.eyebrow){font-size:17px;color:rgba(255,255,255,.84);margin:0;max-width:620px}

.footer{background:#11151d;color:#fff;padding-top:60px}
.footer-grid{display:grid;grid-template-columns:1fr 1.1fr;gap:70px;align-items:start;padding-bottom:48px}
.footer-brand>img{width:290px;filter:brightness(0) invert(1);opacity:.92;margin-bottom:26px}
.footer-brand h3{font-size:19px;margin:0 0 14px}
.footer-brand p{margin:7px 0;color:#c8d0dc;font-size:14px}
.footer-contact h3{margin:0 0 22px;font-size:18px}
.qr-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:18px}
.qr-grid figure{margin:0;text-align:center;color:#e9eef7;font-size:14px}
.qr-grid img{width:132px;aspect-ratio:1/1;object-fit:cover;background:#fff;padding:6px;margin:0 auto 10px;border-radius:8px}
.footer-bottom{border-top:1px solid rgba(255,255,255,.08);padding:18px 0 22px;color:#7f8a9a;font-size:12px;text-align:center}
.back-top{position:fixed;right:24px;bottom:24px;width:46px;height:46px;border-radius:50%;border:0;background:var(--blue);color:#fff;box-shadow:0 10px 28px rgba(31,73,147,.28);cursor:pointer;opacity:0;pointer-events:none;transform:translateY(10px);transition:.25s;z-index:40}
.back-top.show{opacity:1;pointer-events:auto;transform:none}

.reveal{opacity:0;transform:translateY(24px);transition:opacity .7s ease,transform .7s ease}
.reveal.visible{opacity:1;transform:none}

@media (max-width:1100px){
  .main-nav{gap:22px;font-size:14px}.brand img{width:210px}
  .feature-grid{grid-template-columns:repeat(2,1fr)}
  .roles-layout{grid-template-columns:1fr 370px 1fr;gap:20px}.role-wheel{width:350px;height:350px}.role-wheel::after{inset:72px}
  .tech-row{grid-template-columns:70px 230px 1fr}
}

@media (max-width:900px){
  .site-header{height:72px}.nav-shell{width:min(100% - 32px,1320px)}
  .brand img{width:190px}.nav-toggle{display:block}.main-nav{position:absolute;left:16px;right:16px;top:78px;padding:14px;background:rgba(255,255,255,.98);border:1px solid var(--line);border-radius:18px;box-shadow:0 22px 50px rgba(31,62,113,.15);display:none;flex-direction:column;align-items:stretch;gap:0}.main-nav.open{display:flex}.main-nav a{padding:13px 15px;border-radius:10px}.main-nav a::after{display:none}.main-nav a:hover{background:#f3f6fb}
  .hero{height:650px;min-height:0}.hero-copy h1{font-size:46px}.hero-shade{background:linear-gradient(90deg,rgba(7,20,19,.63),rgba(7,20,19,.30))}
  .roles-layout{grid-template-columns:1fr}.role-notes{grid-template-columns:repeat(2,1fr)}.role-notes.right{grid-template-columns:repeat(3,1fr)}.role-wheel{order:-1}.role-notes.left{order:2}.role-notes.right{order:3}
  .future-grid{grid-template-columns:1fr}.future-map{order:2}.future-copy{text-align:center}.future-copy p:not(.eyebrow){margin-inline:auto}
  .footer-grid{grid-template-columns:1fr}
}

@media (max-width:680px){
  .container{width:min(100% - 30px,var(--container))}.section{padding:76px 0}.section-heading{margin-bottom:38px}.section-heading h2{font-size:34px}.section-heading p:last-child{font-size:15px}
  .hero{height:610px}.hero-copy{top:52%}.hero-copy h1{font-size:38px}.hero-copy>p:not(.eyebrow){font-size:16px}.hero-actions{flex-wrap:wrap}.sound-toggle{right:16px;bottom:16px}
  .feature-grid{grid-template-columns:1fr}.feature-media{height:220px}
  .rescue-system{padding:56px 18px 26px;border-radius:24px}.rescue-line{display:none}.device-grid{grid-template-columns:repeat(2,1fr);gap:26px 10px}.device-pill{min-width:118px;font-size:15px}.device-orb{width:122px;height:122px;font-size:14px;margin-top:18px}.service-panel{grid-template-columns:repeat(2,1fr);margin-top:34px;padding:14px}.service-panel span{font-size:13px}
  .role-wheel{width:310px;height:310px}.role-wheel::after{inset:62px}.wheel-label{font-size:13px}.wheel-label.bottom-right{right:46px;bottom:44px}.wheel-label.bottom-left{left:36px;bottom:45px}.role-notes,.role-notes.right{grid-template-columns:1fr}
  .tech-row{grid-template-columns:56px 1fr;gap:12px 18px;padding:26px 10px}.tech-letter{font-size:48px}.tech-title h3{font-size:21px}.tech-row p{grid-column:1/-1;font-size:15px}
  .future-copy h2{font-size:34px}.future-section{padding:74px 0}
  .footer-grid{gap:42px}.qr-grid{gap:8px}.qr-grid img{width:100%;max-width:116px}.footer-brand>img{width:240px}
}