:root {
  --ink: #111827;
  --ink-2: #1f2937;
  --paper: #f8fafc;
  --card: #ffffff;
  --line: #dbe3ee;
  --muted: #667085;
  --signal: #f97316;
  --signal-dark: #c2410c;
  --cyan: #0ea5e9;
  --green: #10b981;
  --shadow: 0 20px 50px rgba(17, 24, 39, 0.12);
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  background: var(--paper);
  color: var(--ink);
  font-family: "Helvetica Neue", "PingFang SC", "Microsoft YaHei", Arial, sans-serif;
  line-height: 1.6;
  margin: 0;
  padding-bottom: 4rem;
}
a { color: inherit; text-decoration: none; }
.site-nav {
  align-items: center;
  background: rgba(17, 24, 39, 0.94);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid rgba(255,255,255,0.1);
  display: flex;
  gap: 1.5rem;
  justify-content: space-between;
  left: 0;
  padding: 0.9rem clamp(1rem, 4vw, 4rem);
  position: fixed;
  right: 0;
  top: 0;
  z-index: 20;
}
.brand { color: #fff; font-size: 1.2rem; font-weight: 900; letter-spacing: 0.03em; }
.brand span { color: var(--signal); }
.nav-links { align-items: center; display: flex; gap: 1rem; }
.nav-links a { color: rgba(255,255,255,0.72); font-size: 0.92rem; }
.nav-links a:hover, .nav-main { color: #fff !important; }
.nav-cta, .btn {
  border: 0;
  border-radius: 0.45rem;
  cursor: pointer;
  display: inline-flex;
  font-weight: 800;
  justify-content: center;
  padding: 0.78rem 1.1rem;
}
.nav-cta, .btn-primary { background: var(--signal); color: #1b1007; }
.btn-primary:hover { background: var(--signal-dark); color: #fff; }
.btn-ghost { border: 1px solid rgba(255,255,255,0.45); color: #fff; }
.hero {
  align-items: center;
  display: grid;
  gap: clamp(2rem, 4vw, 5rem);
  grid-template-columns: minmax(0, 1fr) minmax(320px, 0.82fr);
  min-height: 760px;
  padding: 8.5rem clamp(1rem, 5vw, 5rem) 5rem;
}
.hardware-hero {
  background:
    linear-gradient(115deg, rgba(17,24,39,0.98), rgba(17,24,39,0.8) 54%, rgba(249,115,22,0.5)),
    url("https://images.unsplash.com/photo-1485575301924-6891ef935dcd?auto=format&fit=crop&w=1900&q=80");
  background-position: center;
  background-size: cover;
  color: #fff;
}
.eyebrow {
  color: #fdba74;
  font-size: 0.78rem;
  font-weight: 900;
  letter-spacing: 0.16em;
  margin: 0 0 0.7rem;
  text-transform: uppercase;
}
.hero h1 {
  font-size: clamp(2.35rem, 5.2vw, 5.4rem);
  font-weight: 950;
  letter-spacing: 0;
  line-height: 1.03;
  margin: 0;
  max-width: 980px;
}
.hero-lead {
  color: rgba(255,255,255,0.78);
  font-size: 1.12rem;
  margin: 1.5rem 0;
  max-width: 780px;
}
.hero-actions { display: flex; flex-wrap: wrap; gap: 0.85rem; }
.fine-print { color: rgba(255,255,255,0.52); font-size: 0.82rem; margin-top: 1rem; }
.device-rack {
  background: rgba(255,255,255,0.11);
  border: 1px solid rgba(255,255,255,0.22);
  border-radius: 0.7rem;
  box-shadow: 0 30px 70px rgba(0,0,0,0.28);
  padding: 1.2rem;
}
.rack-header {
  align-items: center;
  display: flex;
  justify-content: space-between;
  margin-bottom: 1rem;
}
.rack-header span { color: rgba(255,255,255,0.66); }
.rack-header strong { color: #fdba74; }
.device-card {
  align-items: center;
  background: rgba(255,255,255,0.1);
  border: 1px solid rgba(255,255,255,0.14);
  border-radius: 0.55rem;
  display: flex;
  gap: 0.9rem;
  margin-bottom: 0.8rem;
  padding: 1rem;
}
.device-card i {
  align-items: center;
  background: rgba(249,115,22,0.18);
  border-radius: 0.5rem;
  color: #fdba74;
  display: flex;
  font-size: 1.8rem;
  height: 3.5rem;
  justify-content: center;
  width: 3.5rem;
}
.device-card.cold i { background: rgba(14,165,233,0.18); color: #7dd3fc; }
.device-card.hot { border-color: rgba(249,115,22,0.42); }
.device-card strong, .device-card span { display: block; }
.device-card span { color: rgba(255,255,255,0.62); font-size: 0.86rem; }
.rack-flow {
  align-items: center;
  display: grid;
  gap: 0.45rem;
  grid-template-columns: 1fr auto 1fr auto 1fr auto 1fr;
  margin-top: 1rem;
}
.rack-flow span {
  background: rgba(255,255,255,0.08);
  border-radius: 0.35rem;
  color: rgba(255,255,255,0.76);
  font-size: 0.85rem;
  font-weight: 800;
  padding: 0.45rem;
  text-align: center;
}
.rack-flow i { background: rgba(255,255,255,0.28); display: block; height: 2px; width: 18px; }
.section { padding: 5rem clamp(1rem, 5vw, 5rem); }
.band-light { background: #fff; }
.band-dark { background: var(--ink); color: #fff; }
.section-head { margin: 0 auto 2.2rem; max-width: 860px; text-align: center; }
.section-head.left { margin-left: 0; text-align: left; }
.section-head h2, .bundle-layout h2, .cross-card h2, .contact-copy h2 {
  font-size: clamp(1.9rem, 3.5vw, 3.2rem);
  line-height: 1.15;
  margin: 0 0 0.85rem;
}
.section-head p:not(.eyebrow), .bundle-layout p, .cross-card p, .contact-copy p { color: var(--muted); margin: 0; }
.product-stack { display: grid; gap: 1rem; }
.product-row {
  align-items: flex-start;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 0.6rem;
  box-shadow: 0 14px 34px rgba(17,24,39,0.07);
  display: grid;
  gap: 1.1rem;
  grid-template-columns: auto 1fr;
  padding: 1.5rem;
}
.product-icon {
  align-items: center;
  background: #ffedd5;
  border-radius: 0.55rem;
  color: var(--signal-dark);
  display: flex;
  font-size: 2rem;
  height: 4.2rem;
  justify-content: center;
  width: 4.2rem;
}
.product-row.fuel .product-icon { background: #fef3c7; color: #b45309; }
.product-row.temp .product-icon { background: #e0f2fe; color: #0369a1; }
.product-row span {
  color: var(--signal-dark);
  font-size: 0.78rem;
  font-weight: 900;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}
.product-row h3 { font-size: 1.35rem; margin: 0.25rem 0 0.5rem; }
.product-row p, .product-row li { color: var(--muted); }
.bundle-layout {
  align-items: center;
  display: grid;
  gap: 2rem;
  grid-template-columns: minmax(0, 0.85fr) minmax(320px, 1fr);
}
.bundle-layout .btn { margin-top: 1.2rem; }
.bundle-steps {
  display: grid;
  gap: 0.75rem;
  grid-template-columns: repeat(3, minmax(0, 1fr));
}
.bundle-steps div, .scene-list article, .cross-card, .lead-form {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 0.55rem;
  box-shadow: 0 12px 30px rgba(17,24,39,0.06);
  padding: 1.2rem;
}
.bundle-steps strong {
  color: var(--signal);
  display: block;
  font-family: Consolas, monospace;
  font-size: 1.4rem;
}
.bundle-steps span { color: var(--ink); font-weight: 800; }
.scene-list {
  display: grid;
  gap: 1rem;
  grid-template-columns: repeat(4, minmax(0, 1fr));
}
.scene-list article { background: rgba(255,255,255,0.07); border-color: rgba(255,255,255,0.1); box-shadow: none; }
.scene-list i { color: #fdba74; font-size: 1.8rem; }
.scene-list h3 { font-size: 1.12rem; margin: 0.7rem 0 0.45rem; }
.scene-list p { color: rgba(255,255,255,0.66); margin: 0; }
.cross-card {
  align-items: center;
  display: flex;
  gap: 1rem;
  justify-content: space-between;
  margin: 0 auto;
  max-width: 1100px;
}
.contact-section {
  background:
    linear-gradient(110deg, rgba(17,24,39,0.96), rgba(31,41,55,0.9)),
    url("https://images.unsplash.com/photo-1519003722824-194d4455a60c?auto=format&fit=crop&w=1600&q=80");
  background-size: cover;
  color: #fff;
  display: grid;
  gap: 2rem;
  grid-template-columns: minmax(0, 0.85fr) minmax(320px, 0.7fr);
}
.contact-copy p { color: rgba(255,255,255,0.72); }
.lead-form { background: rgba(255,255,255,0.12); border-color: rgba(255,255,255,0.18); box-shadow: none; }
.lead-form label { color: rgba(255,255,255,0.82); display: block; font-weight: 800; margin-bottom: 0.5rem; }
.lead-form textarea, .lead-form input {
  background: rgba(255,255,255,0.95);
  border: 1px solid transparent;
  border-radius: 0.42rem;
  display: block;
  font: inherit;
  margin-bottom: 0.8rem;
  padding: 0.85rem;
  width: 100%;
}
.lead-form textarea:focus, .lead-form input:focus { border-color: var(--signal); outline: 0; }
.d-none { display: none !important; }
.lead-preview { background: rgba(255,255,255,0.1); border-radius: 0.4rem; color: rgba(255,255,255,0.72); padding: 0.7rem; }
.link-button { background: transparent; border: 0; color: rgba(255,255,255,0.68); cursor: pointer; margin-top: 0.6rem; width: 100%; }
.form-feedback { color: #ffd88a; min-height: 1.2rem; }
.done { color: #fff; text-align: center; }
.done i { color: #fdba74; display: block; font-size: 3rem; }
.done strong, .done span { display: block; }
.site-footer {
  align-items: center;
  background: #090d14;
  color: rgba(255,255,255,0.64);
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  justify-content: center;
  padding: 2rem 1rem;
}
.site-footer a { color: rgba(255,255,255,0.82); }
@media (max-width: 980px) {
  .nav-links { display: none; }
  .hero, .bundle-layout, .contact-section { grid-template-columns: 1fr; }
  .hero { min-height: auto; }
  .bundle-steps, .scene-list { grid-template-columns: 1fr 1fr; }
  .cross-card { align-items: flex-start; flex-direction: column; }
}
@media (max-width: 620px) {
  body { padding-bottom: 0; }
  .site-nav { gap: 0.7rem; }
  .nav-cta { padding: 0.62rem 0.75rem; }
  .hero { padding-top: 7rem; }
  .product-row { grid-template-columns: 1fr; }
  .bundle-steps, .scene-list, .rack-flow { grid-template-columns: 1fr; }
  .rack-flow i { height: 12px; margin: 0 auto; width: 2px; }
}