/* Smart Home Landing - Main Stylesheet */
:root {
  --primary: #00e5cc;
  --primary-dark: #0097b2;
  --bg-dark: #0a1628;
  --bg-mid: #0e2a3a;
  --text-light: #c8d6e5;
  --text-muted: #64748b;
  --white: #ffffff;
  --surface: #f5f7fa;
  --card-bg: #ffffff;
  --border: #e2e8f0;
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; font-size: 16px; }

body {
  font-family: 'PingFang SC', 'Microsoft YaHei', -apple-system, sans-serif;
  color: #1a1a2e;
  background: var(--surface);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

a { text-decoration: none; color: inherit; }
ul { list-style: none; }
img { max-width: 100%; height: auto; display: block; }

.container { max-width: 1280px; margin: 0 auto; padding: 0 40px; }

/* ── Navigation ── */
header {
  background: var(--bg-dark);
  padding: 0 40px;
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: 0 2px 20px rgba(0,0,0,.3);
}
nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
  max-width: 1280px;
  margin: 0 auto;
}
.nav-logo { display: flex; align-items: center; gap: 12px; }
.nav-logo img { height: 44px; width: 44px; border-radius: 10px; object-fit: cover; }
.nav-logo span { color: var(--primary); font-size: 1.25rem; font-weight: 700; letter-spacing: .5px; }
.nav-links { display: flex; gap: 32px; }
.nav-links a {
  color: var(--text-light);
  font-size: .92rem;
  font-weight: 500;
  transition: color .25s;
  padding: 8px 0;
  border-bottom: 2px solid transparent;
}
.nav-links a:hover, .nav-links a.active { color: var(--primary); border-bottom-color: var(--primary); }
.nav-cta {
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  color: var(--bg-dark);
  font-weight: 700;
  padding: 10px 24px;
  border-radius: 8px;
  font-size: .9rem;
  transition: transform .2s, box-shadow .2s;
}
.nav-cta:hover { transform: translateY(-2px); box-shadow: 0 6px 20px rgba(0,229,204,.35); }

/* ── Hero ── */
.hero {
  background: linear-gradient(160deg, var(--bg-dark) 0%, var(--bg-mid) 60%, var(--bg-dark) 100%);
  padding: 80px 40px 100px;
  position: relative;
  overflow: hidden;
}
.hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background: url(/images/hero-bg.jpg) center/cover no-repeat;
  opacity: .12;
}
.hero::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: 0;
  right: 0;
  height: 60px;
  background: linear-gradient(to bottom, transparent, var(--surface));
}
.hero-inner {
  max-width: 1280px;
  margin: 0 auto;
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
}
.badge {
  display: inline-block;
  background: rgba(0,229,204,.15);
  border: 1px solid rgba(0,229,204,.3);
  color: var(--primary);
  font-size: .78rem;
  padding: 4px 14px;
  border-radius: 20px;
  margin-bottom: 24px;
  letter-spacing: .5px;
}
.hero h1 { color: #fff; font-size: 3rem; font-weight: 800; line-height: 1.2; margin-bottom: 20px; }
.hero h1 em { color: var(--primary); font-style: normal; }
.hero p { color: #94a3b8; font-size: 1.1rem; margin-bottom: 32px; max-width: 520px; }
.hero-actions { display: flex; gap: 16px; }
.btn-primary {
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  color: var(--bg-dark);
  font-weight: 700;
  padding: 14px 32px;
  border-radius: 10px;
  font-size: 1rem;
  transition: all .25s;
  border: none;
  cursor: pointer;
  display: inline-block;
}
.btn-primary:hover { transform: translateY(-3px); box-shadow: 0 8px 25px rgba(0,229,204,.4); }
.btn-secondary {
  background: rgba(255,255,255,.08);
  color: #fff;
  border: 1px solid rgba(255,255,255,.2);
  padding: 14px 32px;
  border-radius: 10px;
  font-size: 1rem;
  font-weight: 500;
  transition: all .25s;
  display: inline-block;
  cursor: pointer;
}
.btn-secondary:hover { background: rgba(255,255,255,.15); border-color: rgba(0,229,204,.4); }
.hero-stats { display: flex; gap: 40px; margin-top: 48px; }
.stat-item { text-align: center; }
.stat-number { color: var(--primary); font-size: 2rem; font-weight: 800; }
.stat-label { color: var(--text-muted); font-size: .8rem; margin-top: 4px; }
.hero-image img { width: 100%; border-radius: 20px; box-shadow: 0 30px 80px rgba(0,0,0,.5); border: 1px solid rgba(255,255,255,.08); }

/* ── Section commons ── */
section { padding: 80px 40px; max-width: 1280px; margin: 0 auto; }
.section-label { color: var(--primary); font-size: .8rem; font-weight: 700; letter-spacing: 2px; text-transform: uppercase; margin-bottom: 10px; }
.section-title { color: var(--bg-dark); font-size: 2.2rem; font-weight: 800; margin-bottom: 16px; }
.section-desc { color: var(--text-muted); font-size: 1rem; max-width: 600px; margin-bottom: 48px; }

/* ── Features ── */
.features-section { background: var(--white); }
.features-grid { display: grid; grid-template-columns: repeat(4,1fr); gap: 24px; }
.feature-card {
  background: #f8fafc;
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 32px 24px;
  text-align: center;
  transition: all .3s;
}
.feature-card:hover { transform: translateY(-6px); box-shadow: 0 12px 40px rgba(0,0,0,.08); border-color: var(--primary); }
.feature-icon {
  width: 56px; height: 56px;
  background: linear-gradient(135deg, #e0fcf8, #c7f5ee);
  border-radius: 14px;
  display: flex; align-items: center; justify-content: center;
  margin: 0 auto 20px;
  font-size: 1.6rem;
}
.feature-card h3 { color: var(--bg-dark); font-size: 1.05rem; font-weight: 700; margin-bottom: 10px; }
.feature-card p { color: var(--text-muted); font-size: .85rem; }

/* ── Products ── */
.products-section { background: var(--surface); }
.products-grid { display: grid; grid-template-columns: repeat(3,1fr); gap: 28px; }
.product-card { background: var(--card-bg); border-radius: 16px; overflow: hidden; border: 1px solid var(--border); transition: all .3s; }
.product-card:hover { transform: translateY(-4px); box-shadow: 0 10px 35px rgba(0,0,0,.1); }
.product-img { height: 200px; overflow: hidden; }
.product-img img { width: 100%; height: 100%; object-fit: cover; transition: transform .4s; }
.product-card:hover .product-img img { transform: scale(1.05); }
.product-body { padding: 24px; }
.product-tag { background: #e0fcf8; color: var(--primary-dark); font-size: .72rem; font-weight: 700; padding: 3px 10px; border-radius: 6px; display: inline-block; margin-bottom: 12px; }
.product-body h3 { color: var(--bg-dark); font-size: 1.1rem; font-weight: 700; margin-bottom: 8px; }
.product-body p { color: var(--text-muted); font-size: .85rem; margin-bottom: 16px; }
.product-link { color: #00b8a9; font-weight: 600; font-size: .88rem; display: inline-flex; align-items: center; gap: 6px; transition: color .2s; }
.product-link:hover { color: var(--primary-dark); }
.product-link::after { content: '\2192'; transition: transform .2s; display: inline-block; }
.product-card:hover .product-link::after { transform: translateX(4px); }

/* ── About Section ── */
.about-section { background: var(--white); }
.about-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 60px; align-items: center; }
.about-image img { width: 100%; border-radius: 16px; box-shadow: 0 16px 50px rgba(0,0,0,.1); }
.about-list { margin-top: 24px; }
.about-list li { display: flex; align-items: flex-start; gap: 14px; margin-bottom: 18px; color: #475569; font-size: .95rem; }
.about-list li .check { flex-shrink: 0; width: 24px; height: 24px; background: linear-gradient(135deg, var(--primary), var(--primary-dark)); border-radius: 50%; display: flex; align-items: center; justify-content: center; color: var(--bg-dark); font-size: .75rem; font-weight: 800; margin-top: 2px; }

/* ── Tech Section ── */
.tech-section { background: var(--surface); }
.tech-grid { display: grid; grid-template-columns: repeat(3,1fr); gap: 28px; }
.tech-card { background: var(--card-bg); border-radius: 16px; overflow: hidden; border: 1px solid var(--border); transition: all .3s; }
.tech-card:hover { transform: translateY(-4px); box-shadow: 0 10px 35px rgba(0,0,0,.1); }
.tech-card img { width: 100%; height: 180px; object-fit: cover; }
.tech-card .tech-body { padding: 24px; }
.tech-card h3 { color: var(--bg-dark); font-size: 1.05rem; font-weight: 700; margin-bottom: 8px; }
.tech-card p { color: var(--text-muted); font-size: .85rem; }

/* ── Partners ── */
.partners-section { background: var(--white); }
.partners-grid { display: grid; grid-template-columns: repeat(6,1fr); gap: 20px; }
.partner-item {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 24px 16px;
  text-align: center;
  color: var(--text-muted);
  font-size: .9rem;
  font-weight: 600;
  transition: all .25s;
}
.partner-item:hover { border-color: var(--primary); color: var(--primary); background: #e0fcf8; }

/* ── FAQ ── */
.faq-section { background: var(--surface); }
.faq-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 24px; }
.faq-item { background: var(--card-bg); border: 1px solid var(--border); border-radius: 12px; padding: 24px; }
.faq-item h3 { color: var(--bg-dark); font-size: 1rem; font-weight: 700; margin-bottom: 10px; }
.faq-item p { color: var(--text-muted); font-size: .88rem; line-height: 1.7; }

/* ── Categories ── */
.categories-section { background: var(--white); }
.categories-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 28px; }
.cat-card { background: var(--surface); border-radius: 16px; overflow: hidden; border: 1px solid var(--border); transition: all .3s; position: relative; min-height: 260px; }
.cat-card:hover { transform: translateY(-4px); box-shadow: 0 10px 35px rgba(0,0,0,.1); border-color: var(--primary); }
.cat-card img { width: 100%; height: 100%; position: absolute; inset: 0; object-fit: cover; opacity: .15; }
.cat-card .cat-overlay { position: relative; z-index: 1; padding: 32px; }
.cat-card h3 { color: var(--bg-dark); font-size: 1.3rem; font-weight: 700; margin-bottom: 8px; }
.cat-card p { color: var(--text-muted); font-size: .88rem; margin-bottom: 16px; }
.cat-card a { color: var(--primary-dark); font-weight: 600; font-size: .88rem; }
.cat-card a::after { content: ' \2192'; }

/* ── CTA ── */
.cta-section {
  background: linear-gradient(135deg, var(--bg-dark), var(--bg-mid));
  padding: 80px 40px;
  text-align: center;
  position: relative;
  overflow: hidden;
}
.cta-section::before { content: ''; position: absolute; inset: 0; background: url(/images/section-features.jpg) center/cover no-repeat; opacity: .08; }
.cta-section .section-title { color: var(--white); }
.cta-section .section-desc { color: #94a3b8; margin: 0 auto 40px; }
.cta-section .btn-primary { font-size: 1.1rem; padding: 16px 48px; }

/* ── Footer ── */
footer { background: var(--bg-dark); padding: 48px 40px 24px; color: var(--text-muted); font-size: .85rem; }
.footer-inner {
  max-width: 1280px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 40px;
  margin-bottom: 40px;
}
.footer-brand img { height: 40px; margin-bottom: 16px; }
.footer-brand p { color: var(--text-muted); font-size: .82rem; line-height: 1.7; }
.footer-col h4 { color: var(--text-light); font-size: .9rem; font-weight: 700; margin-bottom: 16px; }
.footer-col ul { line-height: 2.2; }
.footer-col a { color: var(--text-muted); font-size: .85rem; transition: color .2s; }
.footer-col a:hover { color: var(--primary); }
.footer-bottom { border-top: 1px solid rgba(255,255,255,.06); padding-top: 20px; text-align: center; color: #334155; font-size: .78rem; max-width: 1280px; margin: 0 auto; }

/* ── Responsive ── */
@media (max-width: 1024px) {
  .hero-inner { grid-template-columns: 1fr; }
  .hero-image { display: none; }
  .features-grid { grid-template-columns: repeat(2,1fr); }
  .products-grid { grid-template-columns: repeat(2,1fr); }
  .about-grid { grid-template-columns: 1fr; }
  .tech-grid { grid-template-columns: repeat(2,1fr); }
  .partners-grid { grid-template-columns: repeat(3,1fr); }
  .faq-grid { grid-template-columns: 1fr; }
  .footer-inner { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 768px) {
  .nav-links { display: none; }
  .hero h1 { font-size: 2.2rem; }
  .features-grid { grid-template-columns: 1fr; }
  .products-grid { grid-template-columns: 1fr; }
  .tech-grid { grid-template-columns: 1fr; }
  .categories-grid { grid-template-columns: 1fr; }
  .partners-grid { grid-template-columns: repeat(2,1fr); }
  .footer-inner { grid-template-columns: 1fr; }
  section { padding: 60px 20px; }
}