:root {
  --ink: #17202a;
  --muted: #66717f;
  --paper: #f5f1e8;
  --panel: #fffaf0;
  --steel: #263849;
  --orange: #e66722;
  --amber: #f2b84b;
  --line: rgba(23, 32, 42, .14);
  --shadow: 0 24px 80px rgba(18, 31, 45, .16);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: "Microsoft YaHei", "PingFang SC", sans-serif;
  color: var(--ink);
  background:
    radial-gradient(circle at 12% 10%, rgba(230, 103, 34, .18), transparent 30%),
    radial-gradient(circle at 86% 4%, rgba(38, 56, 73, .18), transparent 28%),
    linear-gradient(135deg, #f7f0e3 0%, #eef0ed 100%);
}

a { color: inherit; text-decoration: none; }

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 18px clamp(18px, 4vw, 58px);
  background: rgba(245, 241, 232, .82);
  backdrop-filter: blur(18px);
  border-bottom: 1px solid var(--line);
}

.brand { display: flex; align-items: center; gap: 12px; }
.brand-mark {
  display: grid;
  place-items: center;
  width: 44px;
  height: 44px;
  border-radius: 14px;
  color: #fff;
  background: linear-gradient(145deg, var(--steel), #0d141c);
  box-shadow: 0 10px 24px rgba(38, 56, 73, .25);
  font-weight: 900;
}
.brand strong { display: block; font-size: 18px; letter-spacing: .06em; }
.brand small { display: block; color: var(--muted); font-size: 10px; letter-spacing: .16em; }

.nav { display: flex; align-items: center; gap: 18px; color: #34404c; font-size: 14px; }
.nav a { transition: color .2s ease; }
.nav a:hover { color: var(--orange); }
.nav-cta {
  padding: 10px 16px;
  color: #fff !important;
  background: var(--orange);
  border-radius: 999px;
  box-shadow: 0 12px 28px rgba(230, 103, 34, .24);
}

.hero {
  display: grid;
  grid-template-columns: minmax(0, 1.08fr) minmax(300px, .92fr);
  gap: clamp(28px, 5vw, 70px);
  align-items: center;
  min-height: 720px;
  padding: 76px clamp(20px, 6vw, 86px) 54px;
  overflow: hidden;
}

.eyebrow {
  margin: 0 0 12px;
  color: var(--orange);
  font-size: 13px;
  font-weight: 800;
  letter-spacing: .18em;
  text-transform: uppercase;
}

h1, h2, h3, p { margin-top: 0; }
h1 {
  margin-bottom: 22px;
  font-size: clamp(42px, 7vw, 82px);
  line-height: .98;
  letter-spacing: -.06em;
}
h1 span { color: var(--steel); }
.lead {
  max-width: 760px;
  color: #3d4a55;
  font-size: clamp(17px, 2vw, 22px);
  line-height: 1.8;
}

.hero-actions { display: flex; flex-wrap: wrap; gap: 14px; margin: 32px 0 26px; }
.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 0 22px;
  border-radius: 999px;
  font-weight: 800;
}
.primary { color: #fff; background: var(--orange); box-shadow: 0 18px 38px rgba(230, 103, 34, .25); }
.ghost { border: 1px solid var(--line); background: rgba(255, 250, 240, .62); }
.trust-row { display: flex; flex-wrap: wrap; gap: 10px; }
.trust-row span {
  padding: 8px 12px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: rgba(255, 255, 255, .36);
  color: #46535f;
  font-size: 13px;
}

.hero-visual {
  position: relative;
  display: grid;
  place-items: center;
  min-height: 520px;
}
.hero-visual::before {
  content: "";
  position: absolute;
  inset: 12% 2% 10% 8%;
  border-radius: 40% 60% 48% 52%;
  background: linear-gradient(145deg, rgba(38, 56, 73, .96), rgba(18, 28, 38, .96));
  box-shadow: var(--shadow);
  transform: rotate(-7deg);
}
.fan-shell {
  position: relative;
  width: min(430px, 82vw);
  aspect-ratio: 1;
  border: 22px solid #f4efe5;
  border-radius: 50%;
  background: radial-gradient(circle, #dce1df 0 8%, #87939c 9% 18%, #263849 19% 100%);
  box-shadow: inset 0 0 0 18px rgba(255,255,255,.08), 0 26px 60px rgba(0,0,0,.26);
  animation: breathe 5s ease-in-out infinite;
}
.fan-ring { position: absolute; inset: 21%; border: 2px dashed rgba(255,255,255,.34); border-radius: 50%; }
.blade {
  position: absolute;
  left: 50%; top: 50%;
  width: 38%; height: 15%;
  border-radius: 80% 20% 80% 20%;
  background: linear-gradient(90deg, var(--amber), var(--orange));
  transform-origin: 0 50%;
  filter: drop-shadow(0 8px 12px rgba(0,0,0,.18));
}
.b1 { transform: rotate(20deg) translateX(8%); }
.b2 { transform: rotate(140deg) translateX(8%); }
.b3 { transform: rotate(260deg) translateX(8%); }
.hub { position: absolute; inset: 39%; border-radius: 50%; background: #f7f0e3; box-shadow: inset 0 0 0 14px #d7d1c5; }
.spec-card {
  position: absolute;
  right: 0;
  bottom: 42px;
  max-width: 285px;
  padding: 18px;
  border: 1px solid rgba(255,255,255,.48);
  border-radius: 22px;
  color: #fff;
  background: rgba(230, 103, 34, .88);
  backdrop-filter: blur(10px);
  box-shadow: 0 20px 44px rgba(0,0,0,.18);
}
.spec-card strong, .spec-card span { display: block; }
.spec-card span { margin-top: 6px; color: rgba(255,255,255,.86); font-size: 14px; line-height: 1.7; }

.section { padding: 72px clamp(20px, 6vw, 86px); }
.intro {
  padding-top: 34px;
  padding-bottom: 34px;
  border-block: 1px solid var(--line);
  background: rgba(255, 250, 240, .48);
}
.intro p { margin: 0; max-width: 1120px; font-size: 22px; line-height: 1.8; }
.section-head { margin-bottom: 28px; }
h2 { font-size: clamp(32px, 4vw, 52px); line-height: 1.05; letter-spacing: -.04em; }
.grid { display: grid; gap: 18px; }
.cards { grid-template-columns: repeat(4, minmax(0, 1fr)); }
.card {
  min-height: 230px;
  padding: 28px;
  border: 1px solid var(--line);
  border-radius: 30px;
  background: rgba(255, 250, 240, .68);
  box-shadow: 0 18px 46px rgba(38, 56, 73, .08);
  transition: transform .22s ease, box-shadow .22s ease;
}
.card:hover { transform: translateY(-6px); box-shadow: 0 24px 60px rgba(38, 56, 73, .14); }
.card h3 { font-size: 24px; }
.card p, .split p, details p { color: var(--muted); line-height: 1.8; }

.split { display: grid; grid-template-columns: .85fr 1fr; gap: 44px; align-items: start; }
.feature-list { display: grid; gap: 14px; margin: 0; padding: 0; list-style: none; }
.feature-list li {
  padding: 22px 24px;
  border-left: 6px solid var(--orange);
  border-radius: 18px;
  background: rgba(255, 250, 240, .72);
  font-weight: 800;
}
.dark-panel {
  margin: 0 clamp(20px, 6vw, 86px);
  padding-inline: clamp(22px, 5vw, 58px);
  border-radius: 42px;
  color: #fff;
  background: linear-gradient(135deg, #17202a, #263849 62%, #412514);
  box-shadow: var(--shadow);
}
.dark-panel .eyebrow { color: var(--amber); }
.advantage-grid { grid-template-columns: repeat(3, 1fr); }
.advantage-grid div { padding: 26px; border: 1px solid rgba(255,255,255,.16); border-radius: 26px; background: rgba(255,255,255,.06); }
.advantage-grid strong { display: block; margin-bottom: 10px; font-size: 24px; }
.advantage-grid span { color: rgba(255,255,255,.76); line-height: 1.75; }

.knowledge details {
  margin-bottom: 12px;
  padding: 22px 24px;
  border: 1px solid var(--line);
  border-radius: 22px;
  background: rgba(255, 250, 240, .72);
}
summary { cursor: pointer; font-weight: 900; font-size: 18px; }

.contact {
  display: grid;
  grid-template-columns: 1fr 380px;
  gap: 36px;
  align-items: center;
}
.contact-card {
  display: grid;
  gap: 8px;
  padding: 30px;
  border-radius: 32px;
  background: var(--panel);
  border: 1px solid var(--line);
  box-shadow: var(--shadow);
}
.contact-card span { color: var(--muted); font-size: 13px; }
.contact-card strong, .contact-card a { font-size: 24px; font-weight: 900; }
.contact-card a { color: var(--orange); }
.footer {
  padding: 32px clamp(20px, 6vw, 86px) 92px;
  border-top: 1px solid var(--line);
  color: var(--muted);
}
.footer p { margin: 6px 0; }
.float-call {
  position: fixed;
  right: 22px;
  bottom: 22px;
  z-index: 30;
  padding: 14px 18px;
  border-radius: 999px;
  color: #fff;
  background: var(--orange);
  box-shadow: 0 18px 40px rgba(230, 103, 34, .34);
  font-weight: 900;
}

@keyframes breathe {
  0%, 100% { transform: rotate(-3deg) scale(1); }
  50% { transform: rotate(3deg) scale(1.025); }
}

@media (max-width: 920px) {
  .nav { display: none; }
  .hero, .split, .contact { grid-template-columns: 1fr; }
  .hero { min-height: auto; padding-top: 46px; }
  .cards, .advantage-grid { grid-template-columns: 1fr; }
  .dark-panel { margin-inline: 20px; }
  .hero-visual { min-height: 420px; }
}