*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
:root {
  --green: #30B08F;
  --green-bg: rgba(48,176,143,0.08);
  --red: #ff4d4f;
  --red-bg: rgba(255,77,79,0.06);
  --blue: #409EFF;
  --orange: #E6A23C;
  --dark: #2c3e50;
  --text: #303133;
  --text-secondary: #606266;
  --text-muted: #909399;
  --bg: #f5f7fa;
  --white: #FFFFFF;
  --shadow: 0 4px 24px rgba(0,0,0,0.08);
  --shadow-lg: 0 8px 40px rgba(0,0,0,0.12);
}
html { scroll-behavior: smooth; }
body {
  font-family: "Microsoft YaHei", "PingFang SC", "Helvetica Neue", sans-serif;
  color: var(--text);
  background: var(--white);
  line-height: 1.6;
}

/* Navigation */
.nav {
  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
  background: rgba(255,255,255,0.95);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid rgba(0,0,0,0.06);
  padding: 0 20px; height: 64px;
  display: flex; align-items: center; justify-content: space-between;
}
.nav-brand { display: flex; align-items: center; gap: 10px; }
.nav-logo { width: 40px; height: 40px; }
.nav-title { font-size: 20px; font-weight: 700; color: var(--dark); white-space: nowrap; }
.nav-title span { color: var(--green); }
.nav-links { display: flex; gap: 40px; list-style: none; }
.nav-links a { text-decoration: none; color: var(--text-secondary); font-size: 15px; transition: color .2s; }
.nav-links a:hover { color: var(--green); }

/* Hero */
.hero {
  min-height: 100vh; display: flex; align-items: center; justify-content: center;
  background: var(--dark); position: relative; overflow: hidden; padding: 120px 80px 100px;
}
.hero::before {
  content: ''; position: absolute; top: -50%; right: -20%; width: 800px; height: 800px;
  background: radial-gradient(circle, rgba(48,176,143,0.1) 0%, transparent 70%);
}
.hero::after {
  content: ''; position: absolute; bottom: -20%; left: -10%; width: 600px; height: 600px;
  background: radial-gradient(circle, rgba(64,158,255,0.06) 0%, transparent 70%);
}
.hero-inner { text-align: center; position: relative; z-index: 1; max-width: 960px; }
.hero-line { width: 200px; height: 1px; background: rgba(48,176,143,0.25); margin: 0 auto 60px; }
.hero h1 {
  font-size: 56px; font-weight: 700; color: var(--white); letter-spacing: 4px; margin-bottom: 16px;
}
.hero-subtitle { font-size: 28px; color: rgba(255,255,255,0.7); margin-bottom: 40px; }
.hero-divider { width: 80px; height: 2px; background: rgba(48,176,143,0.4); margin: 0 auto 40px; }
.hero-tags {
  color: var(--green); font-size: 24px; font-weight: 500; letter-spacing: 2px; margin-bottom: 60px;
}
.hero-scroll { color: rgba(255,255,255,0.35); font-size: 22px; }
.hero-scroll::after { content: ' ↓'; }

/* Sections */
section { padding: 120px 80px; }
.section-header { text-align: center; margin-bottom: 80px; }
.section-label {
  display: inline-flex; align-items: center; gap: 10px;
  font-size: 22px; font-weight: 500; color: var(--green); margin-bottom: 20px;
}
.section-label::before { content: ''; width: 8px; height: 8px; border-radius: 50%; background: var(--green); }
.section-header h2 { font-size: 48px; font-weight: 700; color: var(--text); }
.section-header p { font-size: 28px; color: var(--text-muted); margin-top: 16px; max-width: 750px; margin-left: auto; margin-right: auto; }

/* Feature Cards */
.features-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 40px; max-width: 1200px; margin: 0 auto; }
.feature-card {
  background: var(--white); border-radius: 12px; padding: 48px 36px;
  box-shadow: var(--shadow); transition: transform .3s, box-shadow .3s;
  border-top: 4px solid var(--green);
}
.feature-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); }
.feature-card:nth-child(3) { border-top-color: var(--orange); }
.feature-card:nth-child(2) { border-top-color: var(--blue); }
.feature-icon { width: 64px; height: 64px; border-radius: 12px; display: flex; align-items: center; justify-content: center; font-size: 32px; margin-bottom: 24px; }
.feature-icon img { width: 36px; height: 36px; }
.feature-card:nth-child(1) .feature-icon { background: var(--green-bg); color: var(--green); }
.feature-card:nth-child(3) .feature-icon { background: rgba(230,162,60,0.08); color: var(--orange); }
.feature-card:nth-child(2) .feature-icon { background: rgba(64,158,255,0.08); color: var(--blue); }
.feature-card h3 { font-size: 28px; font-weight: 700; margin-bottom: 12px; color: var(--text); }
.feature-card p { font-size: 18px; color: var(--text-muted); line-height: 1.7; }
.feature-card .highlight { color: var(--green); font-weight: 500; }

/* Screenshot Showcase */
.showcase { background: var(--bg); }
.showcase-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 60px; max-width: 1200px; margin: 0 auto; align-items: center; }
.showcase-grid.reverse { direction: rtl; }
.showcase-grid.reverse > * { direction: ltr; }
.showcase-img {
  width: 100%; border-radius: 12px; box-shadow: var(--shadow-lg);
  border: 1px solid rgba(0,0,0,0.06);
}
.skh-img {
  width: 100%; height: 290px; border-radius: 12px; box-shadow: var(--shadow-lg);
  border: 1px solid rgba(0,0,0,0.06);
}
.showcase-text h3 { font-size: 36px; font-weight: 700; margin-bottom: 16px; }
.showcase-text p { font-size: 20px; color: var(--text-muted); line-height: 1.8; margin-bottom: 24px; }
.showcase-text .badge {
  display: inline-block; padding: 6px 18px; border-radius: 20px;
  background: var(--green-bg); color: var(--green); font-size: 18px; font-weight: 500;
}
.showcase-text .badge.red { background: var(--red-bg); color: var(--red); }
.showcase-text .badge.blue { background: rgba(64,158,255,0.08); color: var(--blue); }

/* Alarm Flow */
.flow { background: var(--white); }
.flow-steps { display: grid; grid-template-columns: repeat(4, 1fr); gap: 30px; max-width: 1200px; margin: 0 auto; }
.flow-step { text-align: center; position: relative; }
.flow-step::after {
  content: '→'; position: absolute; right: -30px; top: 36px;
  font-size: 28px; color: var(--text-muted);
}
.flow-step:last-child::after { content: none; }
.flow-num {
  width: 64px; height: 64px; border-radius: 50%; display: flex; align-items: center; justify-content: center;
  color: #fff; font-size: 28px; font-weight: 700; margin: 0 auto 20px;
}
.flow-step:nth-child(1) .flow-num { background: var(--red); }
.flow-step:nth-child(2) .flow-num { background: var(--orange); }
.flow-step:nth-child(3) .flow-num { background: var(--blue); }
.flow-step:nth-child(4) .flow-num { background: var(--green); }
.flow-step h4 { font-size: 22px; font-weight: 700; margin-bottom: 8px; }
.flow-step p { font-size: 16px; color: var(--text-muted); }

/* Device Icons */
.devices { background: var(--bg); }
.device-grid { display: flex; justify-content: center; gap: 60px; flex-wrap: wrap; max-width: 1100px; margin: 60px auto 0; }
.device-item { text-align: center; }
.device-circle {
  width: 80px; height: 80px; border-radius: 50%; background: rgba(64,158,255,0.08);
  display: flex; align-items: center; justify-content: center; margin: 0 auto 16px;
}
.device-circle img { width: 40px; height: 40px; }
.device-item span { font-size: 18px; color: var(--text-secondary); font-weight: 500; }

/* Image Carousel */
.carousel { position: relative; width: 100%; border-radius: 12px; overflow: hidden; box-shadow: var(--shadow-lg); }
.carousel-slides { display: flex; transition: transform .6s cubic-bezier(0.4,0,0.2,1); }
.carousel-slides img { width: 100%; height: 400px; object-fit: contain; background: #f0f0f0; flex-shrink: 0; display: block; }
.carousel-dots { position: absolute; bottom: 16px; left: 50%; transform: translateX(-50%); display: flex; gap: 10px; }
.carousel-dots button { width: 10px; height: 10px; border-radius: 50%; border: none; background: rgba(255,255,255,0.5); cursor: pointer; padding: 0; transition: background .3s, transform .3s; }
.carousel-dots button.active { background: #fff; transform: scale(1.3); }
.carousel-arrow { position: absolute; top: 50%; transform: translateY(-50%); width: 40px; height: 40px; border-radius: 50%; border: none; background: rgba(255,255,255,0.85); cursor: pointer; font-size: 18px; color: var(--text-secondary); display: flex; align-items: center; justify-content: center; opacity: 0; transition: opacity .3s; }
.carousel:hover .carousel-arrow { opacity: 1; }
.carousel-arrow.prev { left: 12px; }
.carousel-arrow.next { right: 12px; }

/* Comparison */
.compare { background: var(--white); }
.compare-flex { display: grid; grid-template-columns: 1fr auto 1fr; gap: 40px; max-width: 1100px; margin: 0 auto; align-items: center; }
.compare-card { border-radius: 12px; padding: 48px 40px; }
.compare-card.old { background: #f0f0f0; }
.compare-card.new { background: var(--white); border: 1px solid rgba(48,176,143,0.3); }
.compare-card h4 { font-size: 24px; margin-bottom: 28px; display: flex; align-items: center; gap: 10px; }
.compare-card.old h4 { color: var(--text-muted); }
.compare-card.new h4 { color: var(--green); }
.compare-card ul { list-style: none; }
.compare-card li { font-size: 20px; padding: 12px 0; display: flex; align-items: center; gap: 12px; }
.compare-card.old li { color: var(--text-muted); }
.compare-card.new li { color: var(--text); font-weight: 500; }
.compare-card.old li::before { content: '✕'; color: var(--red); font-size: 18px; flex-shrink: 0; }
.compare-card.new li::before { content: '✓'; color: var(--green); font-size: 18px; flex-shrink: 0; }
.compare-arrow { font-size: 40px; color: var(--green); text-align: center; }

/* CTA */
.cta { background: var(--dark); text-align: center; padding: 100px 30px; }
.cta h2 { font-size: 36px; color: var(--white); margin-bottom: 16px; }
.cta p { font-size: 22px; color: rgba(255,255,255,0.55); margin-bottom: 20px; }
.cta-line { width: 100px; height: 2px; background: var(--green); margin: 0 auto 32px; }
.cta-qr { width: 160px; height: 160px; border-radius: 8px; background: #fff; padding: 8px; margin: 0 auto 32px; display: block; }
.cta-tagline { font-size: 18px; color: var(--green); font-weight: 500; }

/* Footer */
.footer { background: #1b2a38; text-align: center; padding: 48px 80px; }
.footer p { color: rgba(255,255,255,0.35); font-size: 16px; }

/* FAQ */
.faq { background: var(--bg); }
.faq-list { max-width: 800px; margin: 0 auto; }
.faq-item { background: var(--white); border-radius: 12px; padding: 28px 32px; margin-bottom: 16px; box-shadow: var(--shadow); }
.faq-q { font-size: 18px; font-weight: 600; color: var(--dark); margin-bottom: 12px; }
.faq-a { font-size: 16px; color: var(--text-secondary); line-height: 1.7; }

/* Page Header */
.page-header { text-align: center; padding: 140px 40px 10px; background: var(--bg); }
.page-header h1 { font-size: 40px; color: var(--dark); margin: 16px 0 12px; }
.page-header p { font-size: 18px; color: var(--text-muted); }

/* Nav active */
.nav-links a.active { color: var(--blue); font-weight: 600; }

/* Contact */
.contact-header{ padding-bottom: 60px;}
.inquiry { padding: 80px 40px; }
.inquiry-grid { max-width: 1100px; margin: 0 auto; display: grid; grid-template-columns: 1.5fr 1fr; gap: 60px; align-items: start; }
.inquiry-form { display: flex; flex-direction: column; gap: 20px; }
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; }
.form-group { display: flex; flex-direction: column; gap: 6px; }
.form-group label { font-size: 15px; color: var(--text-secondary); font-weight: 500; }
.required { color: var(--red); }
.form-group input, .form-group select, .form-group textarea {
  padding: 12px 16px; border: 1px solid rgba(0,0,0,0.12); border-radius: 8px;
  font-size: 16px; color: var(--text); background: var(--white);
  transition: border-color .2s, box-shadow .2s; font-family: inherit;
}
.form-group input:focus, .form-group select:focus, .form-group textarea:focus {
  outline: none; border-color: var(--green); box-shadow: 0 0 0 3px rgba(48,176,143,0.12);
}
.form-group textarea { resize: vertical; }
.btn-submit {
  padding: 16px 32px; border: none; border-radius: 8px; cursor: pointer;
  font-size: 18px; font-weight: 600; color: #fff; background: var(--green);
  transition: background .2s, transform .1s; margin-top: 8px;
}
.btn-submit:hover { background: #279a7a; }
.btn-submit:active { transform: scale(0.98); }
.form-note { font-size: 14px; color: var(--text-muted); text-align: center; }
.inquiry-sidebar { display: flex; flex-direction: column; gap: 32px; align-items: center; padding-top: 20px; }
.sidebar-info { width: 100%; display: flex; flex-direction: column; gap: 24px; }
.sidebar-item h3 { font-size: 14px; color: var(--text-muted); margin-bottom: 6px; font-weight: 400; }
.sidebar-item p { font-size: 18px; color: var(--dark); font-weight: 600; }

/* CTA Button */
.cta-btn {
  display: inline-block; padding: 14px 36px; border-radius: 8px;
  font-size: 18px; font-weight: 600; color: #fff; background: var(--green);
  text-decoration: none; transition: background .2s, transform .1s; margin-top: 24px;
}
.cta-btn:hover { background: #279a7a; }
.cta-btn:active { transform: scale(0.98); }
.contact-qr { text-align: center; }
.contact-qr img { width: 260px; height: 260px; border-radius: 12px; box-shadow: var(--shadow); }
.contact-qr-label { margin-top: 16px; font-size: 16px; color: var(--text-muted); }
.contact-info { display: flex; flex-direction: column; gap: 32px; }
.contact-item h3 { font-size: 16px; color: var(--text-muted); margin-bottom: 8px; font-weight: 400; }
.contact-item p { font-size: 20px; color: var(--dark); font-weight: 600; }

/* Customer Cases */
.cases { background: var(--bg); }
.cases-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 32px; max-width: 1200px; margin: 0 auto; }
.case-card {
  background: var(--white); border-radius: 12px; padding: 36px 32px;
  box-shadow: var(--shadow); transition: transform .3s, box-shadow .3s;
  border-top: 4px solid var(--green);
}
.case-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); }
.case-card:nth-child(2) { border-top-color: var(--blue); }
.case-card:nth-child(3) { border-top-color: var(--orange); }
.case-industry {
  display: inline-block; padding: 4px 14px; border-radius: 20px;
  font-size: 14px; font-weight: 500; margin-bottom: 16px;
  background: var(--green-bg); color: var(--green);
}
.case-card:nth-child(2) .case-industry { background: rgba(64,158,255,0.08); color: var(--blue); }
.case-card:nth-child(3) .case-industry { background: rgba(230,162,60,0.08); color: var(--orange); }
.case-card h3 { font-size: 22px; font-weight: 700; color: var(--dark); margin-bottom: 12px; }
.case-card p { font-size: 16px; color: var(--text-secondary); line-height: 1.7; margin-bottom: 20px; }
.case-tags { display: flex; gap: 8px; flex-wrap: wrap; }
.case-tag {
  display: inline-block; padding: 4px 12px; border-radius: 4px;
  font-size: 13px; color: var(--text-muted); background: rgba(0,0,0,0.04);
}

/* Responsive */
@media (max-width: 1024px) {
  .features-grid, .flow-steps { grid-template-columns: 1fr 1fr; }
  .showcase-grid { grid-template-columns: 1fr; }
  .compare-flex { grid-template-columns: 1fr; }
  .compare-arrow { transform: rotate(90deg); }
  .flow-step::after { content: none; }
}
@media (max-width: 768px) {
  .nav { padding: 0 24px; }
  .nav-links { display: none; }
  .hero h1 { font-size: 36px; }
  .hero-subtitle { font-size: 20px; }
  .hero-tags { font-size: 18px; }
  section { padding: 80px 24px; }
  .features-grid, .flow-steps { grid-template-columns: 1fr; }
  .section-header h2 { font-size: 32px; }
}