:root {
  --navy: #0A2540;
  --navy-light: #13315C;
  --cyan: #00B4D8;
  --cyan-light: #90E0EF;
  --bg: #ffffff;
  --bg-alt: #F6F8FB;
  --bg-navy: #0A2540;
  --text: #1a1a2e;
  --text-light: #5b6472;
  --border-light: #e6eaf0;
  --radius: 12px;
  --radius-lg: 20px;
  --font: 'Noto Sans SC', system-ui, -apple-system, 'Segoe UI', sans-serif;
  --font-serif: 'Noto Serif SC', Georgia, serif;
}
* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  font-family: var(--font);
  color: var(--text);
  background: var(--bg);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}
a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }
ul { list-style: none; }
.container { max-width: 1200px; margin: 0 auto; padding: 0 24px; }

/* ===== Header ===== */
.site-header {
  position: sticky; top: 0; z-index: 100;
  background: rgba(255,255,255,0.92);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border-light);
}
.header-inner {
  max-width: 1200px; margin: 0 auto; padding: 14px 24px;
  display: flex; align-items: center; justify-content: space-between;
}
.logo { display: flex; align-items: center; gap: 10px; font-weight: 700; font-size: 18px; color: var(--navy); }
.logo-mark { 
  width: auto;
  height: 36px; 
  object-fit: contain;
  flex-shrink: 0;
}
.main-nav { display: flex; align-items: center; gap: 30px; }
.header-hotline {
  font-size: 16px; font-weight: 700; color: var(--navy); white-space: nowrap; margin-left: 20px;
}
.main-nav a { font-size: 15px; font-weight: 500; color: var(--text); position: relative; padding: 6px 0; transition: color .2s; }
.main-nav a:hover { color: var(--cyan); }
.main-nav a::after {
  content: ''; position: absolute; left: 0; bottom: 0; height: 2px; width: 0;
  background: var(--cyan); transition: width .25s;
}
.main-nav a:hover::after { width: 100%; }
.main-nav a.nav-cta {
  background: var(--navy); color: #fff; padding: 8px 20px; border-radius: 999px; font-weight: 600;
}
.main-nav a.nav-cta:hover { background: var(--cyan); }
.main-nav a.nav-cta::after { display: none; }

/* ===== 产品中心下拉菜单 ===== */
.nav-item { position: relative; }
.nav-item > .dropdown {
  position: absolute; top: 100%; left: 50%; transform: translateX(-50%);
  background: var(--navy);
  min-width: 190px; padding: 10px 0; border-radius: 10px;
  opacity: 0; visibility: hidden; transition: opacity .2s, visibility .2s;
  box-shadow: 0 12px 30px rgba(0,0,0,0.28); z-index: 100;
}
.nav-item:hover > .dropdown { opacity: 1; visibility: visible; }
.nav-item > .dropdown a {
  display: block; padding: 10px 24px;
  color: #D8DEE8; font-size: 14px; font-weight: 400; white-space: nowrap;
}
.nav-item > .dropdown a:hover { color: var(--cyan); background: rgba(255,255,255,0.06); }
.nav-item > .dropdown a::after { display: none; }

/* ===== 移动端汉堡按钮 ===== */
.nav-toggle {
  display: none; flex-direction: column; justify-content: center; gap: 5px;
  width: 42px; height: 42px; border: none; background: none; cursor: pointer; padding: 10px;
}
.nav-toggle span { display: block; height: 2px; width: 22px; background: var(--navy); border-radius: 2px; transition: all .3s; }
.nav-overlay { display: none; }

/* ===== Hero ===== */
.hero { position: relative; min-height: 620px; display: flex; align-items: center; overflow: hidden; }
.hero-bg { position: absolute; inset: 0; background-size: cover; background-position: center; }
.hero-overlay { position: absolute; inset: 0; background: linear-gradient(120deg, rgba(10,37,64,0.92) 0%, rgba(10,37,64,0.78) 45%, rgba(10,37,64,0.35) 100%); }
.hero-content { position: relative; z-index: 2; max-width: 720px; padding: 80px 24px; color: #fff; }
.hero-eyebrow {
  display: flex; align-items: center; gap: 8px; color: var(--cyan-light);
  font-size: 14px; letter-spacing: 2px; margin-bottom: 20px; text-transform: uppercase;
}
.hero-eyebrow .dot { width: 8px; height: 8px; border-radius: 50%; background: var(--cyan); }
.hero-content h1 {
  font-family: var(--font-serif); font-size: 48px; line-height: 1.25; font-weight: 600; margin-bottom: 24px;
}
.hero-content h1 em { font-style: normal; color: var(--cyan-light); }
.hero-sub { font-size: 17px; color: rgba(255,255,255,0.85); max-width: 560px; margin-bottom: 36px; }
.home-search-bar {
  display: flex; gap: 8px; margin-bottom: 8px;
}
.home-search-bar input {
  width: 280px; max-width: 100%; padding: 10px 18px; border-radius: 999px;
  border: 1px solid var(--border-light); font-size: 14px; outline: none;
}
.home-search-bar input:focus { border-color: var(--cyan); }
.home-search-bar button {
  display: inline-flex; align-items: center; gap: 6px; padding: 10px 22px;
  border-radius: 999px; border: none; background: var(--cyan); color: #0A2540;
  font-size: 14px; font-weight: 600; cursor: pointer; white-space: nowrap;
}
.home-search-bar button:hover { background: #0096B8; }
@media (max-width: 600px) {
  .home-search-bar { width: 100%; }
  .home-search-bar input { flex: 1; width: auto; }
}
.hero-actions { display: flex; gap: 16px; flex-wrap: wrap; justify-content: center; margin-top: 20px; }
.btn {
  display: inline-flex; align-items: center; gap: 8px; padding: 13px 28px;
  border-radius: 999px; font-size: 15px; font-weight: 600; transition: all .25s; cursor: pointer;
}
.btn-primary { background: var(--cyan); color: #0A2540; }
.btn-primary:hover { background: var(--cyan-light); transform: translateY(-2px); }
.btn-ghost { border: 1px solid rgba(255,255,255,0.5); color: #fff; }
.btn-ghost:hover { background: rgba(255,255,255,0.12); }
.btn-outline { border: 1px solid var(--navy); color: var(--navy); }
.btn-outline:hover { background: var(--navy); color: #fff; }
.hero-stats { display: flex; gap: 40px; margin-top: 48px; padding-top: 32px; border-top: 1px solid rgba(255,255,255,0.18); }
.hero-stat-num { font-family: var(--font-serif); font-size: 26px; font-weight: 700; color: #fff; }
.hero-stat-label { font-size: 13px; color: rgba(255,255,255,0.7); }

/* ===== Section ===== */
.section { padding: 84px 0; }
.section-alt { background: var(--bg-alt); }
.section-navy { background: var(--bg-navy); color: #fff; }
.section-header { max-width: 720px; margin-bottom: 48px; }
.section-header.center { margin-left: auto; margin-right: auto; text-align: center; }
.section-eyebrow {
  display: flex; align-items: center; gap: 8px; color: var(--cyan);
  font-size: 13px; letter-spacing: 2px; text-transform: uppercase; margin-bottom: 12px;
}
.section-title { font-family: var(--font-serif); font-size: 34px; font-weight: 700; color: var(--navy); }
.section-navy .section-title { color: #fff; }
.section-desc { color: var(--text-light); margin-top: 12px; font-size: 16px; }

/* ===== Category ===== */
.category-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; }
.category-card {
  background: var(--bg); border: 1px solid var(--border-light); border-radius: var(--radius-lg);
  padding: 28px; transition: all .3s;
}
.category-card:hover { transform: translateY(-4px); box-shadow: 0 16px 40px rgba(10,37,64,0.1); border-color: transparent; }
.category-icon { width: 200px; height: 200px; border-radius: 28px; background: #ffffff; display: flex; align-items: center; justify-content: center; margin-bottom: 20px; overflow: hidden; border: 1px solid var(--border-light); }
.category-icon img { width: 100%; height: 100%; object-fit: cover; }
.category-card h3 { font-size: 18px; margin-bottom: 8px; color: var(--navy); }
.category-card p { font-size: 14px; color: var(--text-light); margin-bottom: 16px; }
.category-link { font-size: 14px; color: var(--cyan); font-weight: 600; }

/* ===== Advantage ===== */
.advantage-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 28px; }
.advantage-item { padding: 12px 4px; }
.advantage-num { font-family: var(--font-serif); font-size: 42px; font-weight: 700; color: var(--cyan); opacity: .6; margin-bottom: 12px; }
.advantage-item h4 { font-size: 20px; margin-bottom: 10px; color: #fff; }
.advantage-item p { font-size: 15px; color: rgba(255,255,255,0.7); }

/* ===== Product ===== */
.product-grid { display: grid; grid-template-columns: repeat(5, 1fr); gap: 20px; }
.product-card {
  background: var(--bg); border-radius: var(--radius-lg); overflow: hidden;
  border: 1px solid var(--border-light); transition: all .3s;
}
.product-card:hover { transform: translateY(-4px); box-shadow: 0 20px 45px rgba(10,37,64,0.12); }
.product-card-img { position: relative; height: 220px; background: #f0f3f8; overflow: hidden; }
.product-card-img img { width: 100%; height: 100%; object-fit: contain; padding: 16px; }
.product-card-tag {
  position: absolute; top: 12px; left: 12px; background: var(--cyan); color: #0A2540;
  font-size: 12px; font-weight: 700; padding: 4px 10px; border-radius: 999px;
}
.product-card-body { padding: 20px 22px 24px; }
.product-card-model { font-size: 12px; color: var(--cyan); font-weight: 700; letter-spacing: 1px; margin-bottom: 6px; }
.product-card-name { font-size: 18px; color: var(--navy); margin-bottom: 8px; font-weight: 700; }
.product-card-desc { font-size: 14px; color: var(--text-light); margin-bottom: 14px; min-height: 44px; }
.product-card-specs { display: flex; flex-wrap: wrap; gap: 8px; margin-bottom: 16px; }
.spec-chip { background: var(--bg-alt); border: 1px solid var(--border-light); color: var(--text-light); font-size: 12px; padding: 3px 10px; border-radius: 999px; }
.product-card-link { font-size: 14px; color: var(--cyan); font-weight: 600; }

/* ===== CTA ===== */
.cta-block { text-align: center; }
.cta-block .section-title { margin-bottom: 12px; }
.cta-block .btn { margin-top: 8px; }

/* ===== Page header ===== */
.page-header { background: var(--bg-navy); color: #fff; padding: 70px 0 60px; }
.page-header .container { max-width: 1200px; margin: 0 auto; padding: 0 24px; }
.page-header h1 { font-family: var(--font-serif); font-size: 38px; font-weight: 700; margin-bottom: 12px; }
.page-header p { font-size: 16px; color: rgba(255,255,255,0.75); }

/* ===== Filter bar ===== */
.filter-bar { display: flex; flex-wrap: wrap; gap: 12px; margin-bottom: 40px; }
.filter-btn {
  padding: 8px 22px; border-radius: 999px; border: 1px solid var(--border-light);
  font-size: 14px; color: var(--text); background: #fff; transition: all .2s;
}
.filter-btn.active, .filter-btn:hover { background: var(--navy); color: #fff; border-color: var(--navy); }

.search-box { margin-left: auto; display: flex; gap: 8px; }
.search-box input {
  width: 240px; padding: 8px 16px; border-radius: 999px;
  border: 1px solid var(--border-light); font-size: 14px; outline: none;
  transition: border-color .2s;
}
.search-box input:focus { border-color: var(--cyan); }
.search-box button {
  padding: 8px 20px; border-radius: 999px; border: none;
  background: var(--cyan); color: #fff; font-size: 14px; cursor: pointer;
  transition: background .2s;
}
.search-box button:hover { background: var(--navy); }
@media (max-width: 768px) {
  .search-box { margin-left: 0; width: 100%; }
  .search-box input { flex: 1; width: auto; }
}

/* ===== Product detail ===== */
.product-detail-hero { padding: 40px 0 60px; }
.breadcrumb { display: flex; gap: 8px; font-size: 14px; color: var(--text-light); margin-bottom: 32px; }
.breadcrumb a:hover { color: var(--cyan); }
.product-detail-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 48px; align-items: start; }
.product-detail-img { border: 1px solid var(--border-light); border-radius: var(--radius-lg); padding: 32px; background: #fafbfd; }
.product-detail-img img { width: 100%; object-fit: contain; }
.model-tag { display: inline-block; background: rgba(0,180,216,0.1); color: var(--cyan); font-weight: 700; font-size: 13px; padding: 4px 12px; border-radius: 999px; margin-bottom: 14px; letter-spacing: 1px; }
.product-detail-info h1 { font-family: var(--font-serif); font-size: 32px; color: var(--navy); margin-bottom: 14px; }
.product-detail-summary { color: var(--text-light); font-size: 15px; margin-bottom: 16px; }
.ai-summary {
  background: #f0f9fc; border-left: 3px solid var(--cyan);
  padding: 14px 18px; border-radius: 0 8px 8px 0;
  font-size: 14px; color: var(--text); line-height: 1.7; margin-bottom: 24px;
}
.product-highlights { margin-bottom: 28px; }
.highlight-item { display: flex; align-items: flex-start; gap: 10px; padding: 8px 0; }
.highlight-icon { width: 20px; height: 20px; border-radius: 50%; background: rgba(0,180,216,0.15); display: flex; align-items: center; justify-content: center; margin-top: 3px; flex-shrink: 0; }
.highlight-item p { font-size: 15px; }
.detail-actions { display: flex; gap: 14px; flex-wrap: wrap; }

.spec-section { padding: 60px 0 80px; }
.spec-table-wrap h3 { font-size: 18px; color: var(--navy); margin-bottom: 12px; }
.spec-table { width: 100%; border-collapse: collapse; margin-bottom: 8px; background: #fff; border-radius: var(--radius); overflow: hidden; }
.spec-table th { width: 200px; text-align: left; padding: 12px 16px; background: var(--bg-alt); font-weight: 600; color: var(--navy); border-bottom: 1px solid var(--border-light); }
.spec-table td { padding: 12px 16px; border-bottom: 1px solid var(--border-light); color: var(--text-light); }
.scene-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.scene-card { background: #fff; border: 1px solid var(--border-light); border-radius: var(--radius); padding: 22px; display: flex; gap: 14px; }
.scene-icon { width: 40px; height: 40px; border-radius: 10px; background: rgba(0,180,216,0.1); display: flex; align-items: center; justify-content: center; flex-shrink: 0; }
.scene-card h4 { font-size: 16px; color: var(--navy); margin-bottom: 6px; }
.scene-card p { font-size: 14px; color: var(--text-light); }

.related-section { padding: 20px 0 84px; }

/* ===== Case ===== */
.case-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 24px; }
.case-card { background: #fff; border: 1px solid var(--border-light); border-radius: var(--radius-lg); overflow: hidden; transition: all .3s; }
.case-card:hover { transform: translateY(-4px); box-shadow: 0 16px 40px rgba(10,37,64,0.1); }
.case-card-img { height: 280px; background: #f0f3f8; overflow: hidden; display: flex; align-items: center; justify-content: center; position: relative; }
.case-card-img img { max-width: 100%; max-height: 100%; object-fit: contain; }
.case-card-img::after {
  content: '重庆迈驰光电科技有限公司';
  position: absolute; top: 50%; left: 50%;
  transform: translate(-50%, -50%) rotate(-30deg);
  font-size: 22px; color: rgba(0,180,216,.3);
  font-weight: 700; letter-spacing: 4px;
  pointer-events: none; white-space: nowrap;
}
.case-card-body { padding: 22px; }
.case-card-tag { display: inline-block; background: rgba(0,180,216,0.1); color: var(--cyan); font-size: 12px; font-weight: 700; padding: 3px 10px; border-radius: 999px; margin-bottom: 10px; }
.case-card-body h3 { font-size: 19px; color: var(--navy); margin-bottom: 8px; }
.case-card-body p { font-size: 14px; color: var(--text-light); margin-bottom: 14px; }
.case-card-meta { display: flex; gap: 16px; font-size: 13px; color: var(--text-light); border-top: 1px solid var(--border-light); padding-top: 12px; }

/* ===== About ===== */
.about-hero { padding: 70px 0; }
.about-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 56px; align-items: center; }
.about-img { border-radius: var(--radius-lg); overflow: hidden; }
.about-img img { width: 100%; object-fit: cover; }
.about-content h2 { font-family: var(--font-serif); font-size: 30px; color: var(--navy); margin-bottom: 18px; }
.about-content p { font-size: 15px; color: var(--text-light); margin-bottom: 16px; }
.about-features { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; margin-top: 24px; }
.about-feature { background: var(--bg-alt); border-radius: var(--radius); padding: 18px; }
.about-feature h5 { font-size: 15px; color: var(--navy); margin-bottom: 6px; }
.about-feature p { font-size: 13px; margin-bottom: 0; }
.timeline-section { padding: 70px 0; }
.timeline { max-width: 640px; margin: 0 auto; position: relative; padding-left: 24px; }
.timeline::before { content: ''; position: absolute; left: 0; top: 0; bottom: 0; width: 2px; background: var(--border-light); }
.timeline-item { position: relative; padding: 0 0 36px 32px; }
.timeline-dot { position: absolute; left: -7px; top: 6px; width: 16px; height: 16px; border-radius: 50%; background: var(--cyan); border: 3px solid #fff; box-shadow: 0 0 0 2px var(--cyan); }
.timeline-year { display: inline-block; background: rgba(0,180,216,0.1); color: var(--cyan); font-weight: 700; font-size: 13px; padding: 3px 12px; border-radius: 999px; margin-bottom: 8px; }
.timeline-content h4 { font-size: 18px; color: var(--navy); margin-bottom: 6px; }
.timeline-content p { font-size: 14px; color: var(--text-light); }

/* ===== Contact ===== */
.contact-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 56px; }
.contact-info h3, .contact-form h3 { font-size: 22px; color: var(--navy); margin-bottom: 24px; }
.contact-item { display: flex; gap: 16px; margin-bottom: 24px; }
.contact-icon { width: 44px; height: 44px; border-radius: 12px; background: rgba(0,180,216,0.1); display: flex; align-items: center; justify-content: center; flex-shrink: 0; }
.contact-icon svg { width: 22px; height: 22px; stroke: var(--cyan); fill: none; }
.contact-item h4 { font-size: 15px; color: var(--navy); margin-bottom: 4px; }
.contact-item p { font-size: 14px; color: var(--text-light); }
.contact-form { background: #fff; border: 1px solid var(--border-light); border-radius: var(--radius-lg); padding: 32px; }
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; margin-bottom: 16px; }
.form-group { display: flex; flex-direction: column; margin-bottom: 16px; }
.form-row + .form-group { margin-top: -16px; }
.form-group label { font-size: 14px; font-weight: 500; color: var(--navy); margin-bottom: 6px; }
.form-group input, .form-group select, .form-group textarea {
  padding: 11px 14px; border: 1px solid var(--border-light); border-radius: 10px; font-size: 14px; font-family: inherit; transition: border .2s; background: #fff;
}
.form-group input:focus, .form-group select:focus, .form-group textarea:focus { outline: none; border-color: var(--cyan); }
.form-submit { background: var(--navy); color: #fff; border: none; padding: 13px 28px; border-radius: 999px; font-size: 15px; font-weight: 600; cursor: pointer; transition: all .25s; }
.form-submit:hover { background: var(--cyan); color: #0A2540; }

/* ===== 智能对话窗口 ===== */
.chat-toggle {
  position: fixed; right: 24px; bottom: 24px; z-index: 300;
  width: 58px; height: 58px; border-radius: 50%;
  background: var(--cyan); color: #fff; border: none; cursor: pointer;
  display: flex; align-items: center; justify-content: center;
  box-shadow: 0 8px 24px rgba(0,180,216,0.4); transition: transform .2s; cursor: grab;
}
.chat-toggle:hover { transform: scale(1.06); }
.chat-toggle-dot {
  position: absolute; top: 4px; right: 4px; width: 12px; height: 12px;
  background: #ff5a5f; border: 2px solid #fff; border-radius: 50%;
}
.chat-panel {
  position: fixed; right: 24px; bottom: 96px; z-index: 300;
  width: 330px; height: 430px; max-width: calc(100vw - 32px);
  background: #fff; border-radius: 18px;
  box-shadow: 0 20px 60px rgba(10,37,64,0.25);
  display: flex; flex-direction: column; overflow: hidden;
  opacity: 0; visibility: hidden; transform: translateY(16px); transition: all .25s;
}
.chat-panel.open { opacity: 1; visibility: visible; transform: translateY(0); }
.chat-head {
  background: var(--navy); color: #fff; padding: 14px 18px;
  display: flex; justify-content: space-between; align-items: center; flex-shrink: 0; cursor: move;
}
.chat-head-title { font-weight: 600; font-size: 15px; }
.chat-close { background: none; border: none; color: #fff; font-size: 24px; cursor: pointer; line-height: 1; }
.chat-body { flex: 1; overflow-y: auto; padding: 16px; background: var(--bg-alt); }
.chat-msg { margin-bottom: 12px; display: flex; }
.chat-msg.user { justify-content: flex-end; }
.chat-bubble { max-width: 82%; padding: 10px 14px; border-radius: 14px; font-size: 14px; line-height: 1.7; word-break: break-word; }
.chat-msg.bot .chat-bubble { background: #fff; border: 1px solid var(--border-light); color: var(--text); border-top-left-radius: 4px; }
.chat-msg.user .chat-bubble { background: var(--cyan); color: #fff; border-top-right-radius: 4px; }
.chat-foot {
  display: flex; gap: 8px; padding: 12px; flex-shrink: 0;
  border-top: 1px solid var(--border-light); background: #fff;
}
.chat-foot input {
  flex: 1; padding: 10px 14px; border: 1px solid var(--border-light);
  border-radius: 999px; font-size: 14px; outline: none; color: var(--text);
}
.chat-foot input:focus { border-color: var(--cyan); }
.chat-foot button {
  background: var(--cyan); color: #fff; border: none; border-radius: 999px;
  padding: 0 18px; font-size: 14px; font-weight: 600; cursor: pointer;
}
@media (max-width: 640px) {
  .chat-toggle { right: 16px; bottom: 16px; width: 52px; height: 52px; }
  .chat-panel { right: 16px; bottom: 80px; width: calc(100vw - 32px); height: 55vh; }
}

/* ===== Footer ===== */
.site-footer { background: #061a2f; color: #cbd5e1; padding: 60px 0 24px; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr 1.4fr; gap: 40px; margin-bottom: 40px; }
.footer-brand .logo { color: #fff; margin-bottom: 16px; }
.footer-brand p { font-size: 14px; color: #94a3b8; line-height: 1.8; }
.footer-col h5 { font-size: 15px; color: #fff; margin-bottom: 16px; font-weight: 600; }
.footer-col ul li { margin-bottom: 10px; }
.footer-col ul li a { font-size: 14px; color: #94a3b8; transition: color .2s; }
.footer-col ul li a:hover { color: var(--cyan); }
.footer-col ul li { font-size: 14px; color: #94a3b8; }
.footer-bottom { border-top: 1px solid rgba(255,255,255,0.08); padding-top: 20px; display: flex; justify-content: space-between; flex-wrap: wrap; gap: 10px; font-size: 13px; color: #64748b; }

/* ===== Responsive ===== */
@media (max-width: 1200px) {
  .product-grid { grid-template-columns: repeat(3, 1fr); }
}
@media (max-width: 992px) {
  .category-grid, .advantage-grid { grid-template-columns: repeat(2, 1fr); }
  .product-grid, .scene-grid { grid-template-columns: repeat(2, 1fr); }
  .product-detail-grid, .about-grid, .contact-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .hero-content h1 { font-size: 38px; }
  .main-nav { gap: 18px; }
}
@media (max-width: 640px) {
  .category-grid, .advantage-grid, .product-grid, .scene-grid, .case-grid, .about-features { grid-template-columns: 1fr; }
  .hero-stats { flex-direction: column; gap: 20px; }
  .form-row { grid-template-columns: 1fr; }
  .section-title { font-size: 28px; }
  .header-inner { justify-content: space-between; }
  .nav-toggle { display: flex; }
  .header-hotline { display: none; }
  .main-nav {
    display: flex; flex-direction: column; gap: 0;
    position: fixed; top: 0; right: -280px; width: 268px; height: 100vh;
    background: var(--bg); box-shadow: -10px 0 30px rgba(10,37,64,0.15);
    padding: 80px 22px 30px; transition: right .3s ease; z-index: 200; overflow-y: auto;
  }
  .main-nav.nav-open { right: 0; }
  .main-nav a { display: block; padding: 13px 4px; font-size: 16px; border-bottom: 1px solid var(--border-light); }
  .main-nav a::after { display: none; }
  .main-nav a.nav-cta { display: inline-flex; margin-top: 16px; }
  .nav-item > .dropdown {
    position: static; transform: none; opacity: 1; visibility: visible;
    background: var(--bg-alt); box-shadow: none; min-width: 0; border-radius: 10px; margin: 8px 0 4px; padding: 6px 0;
  }
  .nav-item > .dropdown a { color: var(--text); padding: 10px 16px; }
  .nav-overlay.show { display: block; position: fixed; inset: 0; background: rgba(10,37,64,0.5); z-index: 150; }
}

.blog-list{display:grid;grid-template-columns:repeat(auto-fill,minmax(340px,1fr));gap:24px;margin-top:30px;}
.blog-card{display:block;padding:28px;border:1px solid var(--border-light);border-radius:12px;transition:all .25s;text-decoration:none;color:inherit;}
.blog-card:hover{border-color:var(--cyan);box-shadow:0 8px 24px rgba(0,180,216,.12);transform:translateY(-2px);}
.blog-card-date{font-size:13px;color:#999;margin-bottom:10px;}
.blog-card h3{font-size:19px;margin-bottom:10px;line-height:1.5;}
.blog-card p{font-size:14px;color:var(--text-light);line-height:1.7;margin-bottom:14px;}
.blog-read{font-size:14px;color:var(--cyan);font-weight:600;}
.article-content h3{font-size:20px;margin:28px 0 12px;color:var(--navy);}
.article-content p{margin-bottom:14px;}
.article-content ul{margin:14px 0 14px 20px;}
.article-content li{margin-bottom:6px;}