/* ============================================
   中网慧通官网 · 黑底金缀风格
   ============================================ */

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

:root {
  --color-bg: #0a0a0a;
  --color-bg-2: #131313;
  --color-bg-3: #1a1a1a;
  --color-gold: #B8902C;
  --color-gold-bright: #D4A93C;
  --color-gold-dim: #8A6E1F;
  --color-gold-glow: rgba(184, 144, 44, 0.4);
  --color-text: #FFFFFF;
  --color-text-2: rgba(255, 255, 255, 0.72);
  --color-text-3: rgba(255, 255, 255, 0.45);
  --color-border: rgba(184, 144, 44, 0.2);
  --color-border-bright: rgba(184, 144, 44, 0.5);
  --font-cn: "PingFang SC", "Microsoft YaHei", "Source Han Sans CN", sans-serif;
  --font-en: "Sora", "Inter", -apple-system, sans-serif;
  --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
}

html {
  scroll-behavior: smooth;
}

body {
  background: var(--color-bg);
  color: var(--color-text);
  font-family: var(--font-cn), var(--font-en);
  line-height: 1.6;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* ============================================
   导航
   ============================================ */
.nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 100;
  padding: 1.5rem 4rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  background: linear-gradient(to bottom, rgba(0,0,0,0.6), transparent);
  transition: background 0.3s;
}

.nav.scrolled {
  background: rgba(0, 0, 0, 0.92);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--color-border);
}

.nav-logo {
  display: flex;
  flex-direction: column;
  text-decoration: none;
  gap: 0.1rem;
}
.logo-cn {
  font-size: 1.3rem;
  font-weight: 500;
  color: var(--color-gold);
  letter-spacing: 0.15em;
}
.logo-en {
  font-size: 0.7rem;
  color: var(--color-text-3);
  letter-spacing: 0.25em;
  font-weight: 400;
}

.nav-menu {
  display: flex;
  gap: 2.5rem;
}
.nav-menu a {
  color: var(--color-text);
  text-decoration: none;
  font-size: 0.95rem;
  font-weight: 400;
  transition: color 0.3s;
  position: relative;
}
.nav-menu a::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 1px;
  background: var(--color-gold);
  transition: width 0.3s;
}
.nav-menu a:hover { color: var(--color-gold); }
.nav-menu a:hover::after { width: 100%; }

/* ============================================
   通用 Section
   ============================================ */
.section {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  padding: 6rem 4rem;
}

.section-inner {
  max-width: 1280px;
  width: 100%;
  margin: 0 auto;
}

.section-tag {
  font-family: var(--font-en);
  font-size: 0.75rem;
  color: var(--color-gold);
  letter-spacing: 0.3em;
  margin-bottom: 1rem;
  font-weight: 500;
}
.section-arch .section-tag {
  letter-spacing: 0.16em;
}

.section-title {
  font-size: 3rem;
  font-weight: 500;
  color: var(--color-text);
  margin-bottom: 1.5rem;
  letter-spacing: 0.08em;
  line-height: 1.2;
}

.section-lead {
  font-size: 1.15rem;
  color: var(--color-text-2);
  margin-bottom: 3rem;
  font-weight: 300;
}

/* ============================================
   首屏 Hero
   ============================================ */
.section-hero {
  position: relative;
  overflow: hidden;
  padding: 0;
  min-height: 100vh;
}

.hero-bg {
  position: absolute;
  inset: 0;
  background: radial-gradient(ellipse at center, #1a1410 0%, var(--color-bg) 70%);
}

.hero-radar {
  position: absolute;
  top: 50%; left: 50%;
  width: 100vmax; height: 100vmax;
  transform: translate(-50%, -50%);
  background: conic-gradient(
    from 0deg,
    transparent 0deg,
    rgba(255, 205, 110, 0.072) 4deg,
    rgba(255, 205, 110, 0.144) 8deg,
    rgba(255, 205, 110, 0.22) 12deg,
    rgba(255, 205, 110, 0.312) 20deg,
    rgba(255, 205, 110, 0.38) 28deg,
    rgba(255, 225, 140, 0.40) 42deg,
    rgba(255, 205, 110, 0.368) 48deg,
    rgba(255, 205, 110, 0.26) 58deg,
    rgba(255, 205, 110, 0.168) 66deg,
    rgba(255, 205, 110, 0.08) 74deg,
    rgba(255, 205, 110, 0.024) 80deg,
    transparent 86deg
  );
  border-radius: 50%;
  animation: radar-spin 8s linear infinite;
  opacity: 1;
  filter: blur(30px) drop-shadow(0 0 30px rgba(255, 205, 110, 0.056));
  -webkit-mask-image: radial-gradient(circle at center, black 0%, black 85%, transparent 100%);
  mask-image: radial-gradient(circle at center, black 0%, black 85%, transparent 100%);
  will-change: transform;
}

@keyframes radar-spin {
  to { transform: translate(-50%, -50%) rotate(360deg); }
}

.hero-glow {
  position: absolute;
  top: 50%; left: 50%;
  width: 800px; height: 800px;
  transform: translate(-50%, -50%);
  background: radial-gradient(circle, rgba(255, 205, 110, 0.30) 0%, transparent 70%);
  filter: blur(50px);
}

.hero-content {
  position: relative;
  z-index: 1;
  text-align: center;
  padding: 0 2rem;
  max-width: 1000px;
}

.hero-title {
  font-size: 6rem;
  font-weight: 500;
  letter-spacing: 0.3em;
  color: var(--color-gold);
  text-shadow: 0 0 60px var(--color-gold-glow);
  margin-bottom: 0.5rem;
  font-family: var(--font-cn);
}

.hero-tagline {
  font-family: var(--font-en);
  font-size: 0.9rem;
  color: var(--color-text-3);
  letter-spacing: 0.5em;
  margin-bottom: 3rem;
  font-weight: 400;
}

.hero-subtitle {
  font-size: 1.5rem;
  color: var(--color-text);
  letter-spacing: 0.15em;
  margin-bottom: 1rem;
  font-weight: 400;
}

.hero-desc {
  font-size: 1.05rem;
  color: var(--color-text-2);
  letter-spacing: 0.1em;
  font-weight: 300;
}

.hero-scroll {
  position: absolute;
  bottom: -120px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.8rem;
}
.scroll-line {
  width: 1px;
  height: 60px;
  background: linear-gradient(to bottom, transparent, var(--color-gold), transparent);
  animation: scroll-pulse 2s ease-in-out infinite;
}
.scroll-text {
  font-family: var(--font-en);
  font-size: 0.7rem;
  color: var(--color-text-3);
  letter-spacing: 0.4em;
}
@keyframes scroll-pulse {
  0%, 100% { opacity: 0.3; transform: scaleY(0.6); }
  50% { opacity: 1; transform: scaleY(1); }
}

/* ============================================
   关于
   ============================================ */
.section-about {
  background: linear-gradient(180deg, var(--color-bg) 0%, var(--color-bg-2) 100%);
}

.about-grid {
  display: grid;
  gap: 1.5rem;
  max-width: 900px;
}
.about-text {
  font-size: 1.05rem;
  color: var(--color-text-2);
  line-height: 1.9;
  letter-spacing: 0.02em;
}

/* 关于我们章节 "了解更多" 按钮（SpaceX 风格） */
.about-cta-wrap {
  max-width: 900px;
  margin-top: 2rem;
}
/* 按钮缩到约 50% 大小（叶总 09-03 要求） */
.about-cta {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  padding: 0.55rem 1.2rem;
  border: 1px solid rgba(255, 255, 255, 0.55);
  background: transparent;
  color: #fff;
  font-size: 0.7rem;
  font-weight: 400;
  letter-spacing: 0.18em;
  text-decoration: none;
  border-radius: 2px;
  transition: background 0.35s ease, color 0.35s ease, border-color 0.35s ease;
}
.about-cta:hover,
.about-cta:focus-visible {
  background: #fff;
  color: #000;
  border-color: #fff;
  outline: none;
}
.cta-arrow {
  display: inline-block;
  font-size: 1em;
  line-height: 1;
  transition: transform 0.35s ease;
}
.about-cta:hover .cta-arrow,
.about-cta:focus-visible .cta-arrow {
  transform: translateX(5px);
}

/* ============================================
   关于我们详细页 · 三章节全屏视频（SpaceX 风）
   ============================================ */
.about-chapter {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  overflow: hidden;
  padding: 9rem 6vw 6rem;
  background: var(--color-bg);
}
.about-chapter .bg-video {
  position: absolute;
  top: 50%;
  left: 50%;
  min-width: 100%;
  min-height: 100%;
  width: auto;
  height: auto;
  transform: translate(-50%, -50%);
  object-fit: cover;
  z-index: 0;
  opacity: 0.55;
  filter: brightness(0.6) contrast(1.05) saturate(0.95);
}
.about-chapter .bg-kenburns {
  position: absolute;
  inset: -16%;
  z-index: 0;
  background: #050505 url('../assets/images/m300-blueprint-wide-v3.png') left center / cover no-repeat;
  opacity: 0.85;
  filter: brightness(0.6) contrast(1.05) saturate(0.95);
  animation: kenburns-slide 48s linear infinite;
  will-change: transform;
}
.about-chapter.right .bg-kenburns {
  background-position: left center;
}
@keyframes kenburns-slide {
  0%   { transform: translateX(-12%); opacity: 0; }
  12%  { opacity: 0.85; }
  88%  { opacity: 0.85; }
  100% { transform: translateX(-2%); opacity: 0; }
}

/* ============================================
   产品页蓝图背景（与关于我们"有眼·有脑·有手"章节同款）
   用法：<body class="bp-bg"> + 两个固定层 .page-bg-blueprint / .page-bg-overlay
   ============================================ */
body.bp-bg { background: #050505; }

.page-bg-blueprint {
  position: fixed;
  inset: -16%;
  z-index: 0;
  background: #050505 url('../assets/images/m300-blueprint-wide-v3.png') center / cover no-repeat;
  opacity: 0.85;
  filter: brightness(0.58) contrast(1.05) saturate(0.95);
  will-change: transform;
  pointer-events: none;
  /* 完全复用关于页"有眼·有脑·有手"的同款动画：从左淡入 → 右移 → 淡出 → 从左重新淡入 → 右移，循环 */
  animation: kenburns-slide 48s linear infinite;
}
/* ============================================
   详情页背景按产品分类切换
   由 product.js 给 body 加 bg-cat-lowalt / bg-cat-station / bg-cat-ground
   - ground(M300 系列, 白底蓝图)  → 沿用 base 的 m300 + brightness(0.58) 压暗
   - lowalt(M450 系列, 黑底白线) → M450BLUE.jpg, 不压暗, 浅遮罩保白线可见
   - station(A304/K系列, 黑底白线) → A304blue.png, 同上
   ============================================ */
body.bg-cat-lowalt .page-bg-blueprint {
  background-image: url('../assets/images/products/M450BLUE.jpg');
  background-size: 75% auto;
  background-position: center center;
  background-repeat: no-repeat;
  filter: brightness(0.33) contrast(1.05);
}
body.bg-cat-station .page-bg-blueprint {
  background-image: url('../assets/images/products/A304blue.png');
  background-size: 75% auto;
  background-position: center center;
  background-repeat: no-repeat;
  filter: brightness(0.26) contrast(1.05);
}
/* 黑底白线类（lowalt / station）遮罩减淡，让蓝图白线清晰可见 */
body.bg-cat-lowalt .page-bg-overlay,
body.bg-cat-station .page-bg-overlay {
  background: linear-gradient(180deg, rgba(0,0,0,0.3) 0%, rgba(0,0,0,0.5) 50%, rgba(0,0,0,0.7) 100%);
}
.page-bg-overlay {
  position: fixed;
  inset: 0;
  z-index: 1;
  pointer-events: none;
  background: linear-gradient(180deg, rgba(0,0,0,0.55) 0%, rgba(0,0,0,0.78) 42%, rgba(0,0,0,0.9) 100%);
}

/* 内容浮于蓝图之上 */
body.bp-bg .nav { z-index: 100; }
body.bp-bg > .section,
body.bp-bg > .product-detail,
body.bp-bg > .footer {
  position: relative;
  z-index: 2;
}

/* 顶层容器透明，露出蓝图底图 */
body.bp-bg .section-allproducts,
body.bp-bg .product-detail,
body.bp-bg .footer {
  background: transparent !important;
}
body.bp-bg .footer { border-top-color: rgba(255,255,255,0.08); }

/* 详情页内部面板半透明 + 轻微模糊，让蓝图透出且保证文字可读 */
body.bp-bg .pd-main-img,
body.bp-bg .pd-thumb,
body.bp-bg .pd-spec-group,
body.bp-bg .pd-feature,
body.bp-bg .pd-other-item {
  background: rgba(18, 18, 18, 0.72);
  backdrop-filter: blur(2px);
  -webkit-backdrop-filter: blur(2px);
}
.about-chapter .video-overlay {
  position: absolute;
  inset: 0;
  z-index: 1;
  pointer-events: none;
}
.about-chapter.left .video-overlay {
  background: linear-gradient(90deg, rgba(0,0,0,0.82) 0%, rgba(0,0,0,0.45) 46%, rgba(0,0,0,0.2) 100%);
}
.about-chapter.right .video-overlay {
  background: linear-gradient(270deg, rgba(0,0,0,0.82) 0%, rgba(0,0,0,0.45) 46%, rgba(0,0,0,0.2) 100%);
}
.about-chapter-inner {
  position: relative;
  z-index: 2;
  width: 100%;
  max-width: 1280px;
  margin: 0 auto;
  display: flex;
}
.about-chapter.left .about-chapter-inner { justify-content: flex-start; }
.about-chapter.right .about-chapter-inner { justify-content: flex-end; }
.about-chapter-text { max-width: 680px; }
.about-chapter.right .about-chapter-text { text-align: left; }
.about-chapter-title {
  font-size: 2.2rem;
  font-weight: 700;
  color: var(--color-text);
  letter-spacing: 0.04em;
  line-height: 1.3;
  margin-bottom: 1.4rem;
  text-wrap: balance;
}
.about-chapter-title::after {
  content: '';
  display: block;
  width: 56px;
  height: 3px;
  background: var(--color-gold);
  margin-top: 1.1rem;
}
.about-chapter.right .about-chapter-title::after { margin-left: 0; }
.about-chapter-body {
  font-size: 1rem;
  line-height: 2;
  color: var(--color-text-2);
  letter-spacing: 0.02em;
  text-wrap: pretty;
}
.about-back {
  position: relative;
  z-index: 2;
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  margin-top: 2.6rem;
  padding: 0.6rem 1.4rem;
  border: 1px solid rgba(255,255,255,0.5);
  color: #fff;
  font-size: 0.85rem;
  letter-spacing: 0.15em;
  text-decoration: none;
  border-radius: 2px;
  transition: background 0.35s ease, color 0.35s ease;
}
.about-back:hover { background: #fff; color: #000; }

@media (max-width: 768px) {
  .about-chapter { padding: 7rem 1.6rem 4rem; }
  .about-chapter-inner { justify-content: center !important; }
  .about-chapter-text { max-width: 100%; text-align: left !important; }
  .about-chapter.right .about-chapter-title::after { margin-left: 0; }
  .about-chapter .video-overlay { background: rgba(0,0,0,0.62); }
}

/* ============================================
   体系化防御架构
   ============================================ */
.section-arch {
  background: var(--color-bg-2);
}

.arch-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2rem;
  margin-top: 2rem;
}

.arch-card {
  background: var(--color-bg-3);
  border: 1px solid var(--color-border);
  padding: 2.5rem;
  border-radius: 4px;
  transition: all 0.4s var(--ease-out);
  position: relative;
  overflow: hidden;
}
.arch-card::before {
  content: '';
  position: absolute;
  top: 0; left: 0;
  width: 100%; height: 2px;
  background: linear-gradient(90deg, transparent, var(--color-gold), transparent);
  transform: translateX(-100%);
  transition: transform 0.6s;
}
.arch-card:hover {
  border-color: var(--color-border-bright);
  transform: translateY(-6px);
  box-shadow: 0 20px 40px rgba(184, 144, 44, 0.1);
}
.arch-card:hover::before {
  transform: translateX(0);
}

.arch-number {
  font-family: var(--font-en);
  font-size: 0.85rem;
  color: var(--color-gold);
  letter-spacing: 0.3em;
  margin-bottom: 1rem;
  font-weight: 500;
}
.arch-card h3 {
  font-size: 1.6rem;
  color: var(--color-text);
  margin-bottom: 0.8rem;
  font-weight: 500;
  letter-spacing: 0.1em;
}
.arch-headline {
  font-size: 1rem;
  color: var(--color-gold-bright);
  margin-bottom: 1.2rem;
  font-weight: 400;
}
.arch-detail {
  font-size: 0.9rem;
  color: var(--color-text-2);
  line-height: 1.7;
}
.arch-bullets {
  margin: 0.4rem 0 0;
  padding: 0;
  list-style: none;
}
.arch-bullets li {
  position: relative;
  font-size: 0.9rem;
  color: var(--color-text-2);
  line-height: 1.7;
  padding-left: 1.1rem;
  margin-bottom: 0.55rem;
}
.arch-bullets li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0.62em;
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background: var(--color-gold);
}

/* ============================================
   产品中心
   ============================================ */
.section-products {
  background: linear-gradient(180deg, var(--color-bg-2) 0%, var(--color-bg) 100%);
}

.products-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
}
/* 首页 4 款主推：一排四个对称摆放（叶总 09-05 要求） */
.products-grid-4 {
  grid-template-columns: repeat(4, 1fr);
}

.product-card {
  background: var(--color-bg-3);
  border: 1px solid var(--color-border);
  padding: 1.5rem;
  border-radius: 4px;
  transition: all 0.4s var(--ease-out);
  cursor: pointer;
}
.product-card:hover {
  border-color: var(--color-border-bright);
  transform: translateY(-4px);
  box-shadow: 0 16px 32px rgba(0, 0, 0, 0.5);
}

/* 产品封面改为竖版（叶总 09-05 要求）：原 180px 定高横版容器已废弃 */
.product-img {
  width: 100%;
  aspect-ratio: 2 / 3;
  height: auto;
  display: block;
  background: linear-gradient(135deg, rgba(184, 144, 44, 0.05), rgba(0,0,0,0));
  border-radius: 4px;
  margin-bottom: 1.2rem;
  overflow: hidden;
}
.product-img img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center;
}
.product-img-software {
  background: linear-gradient(135deg, rgba(184, 144, 44, 0.15), rgba(184, 144, 44, 0.03));
}
.software-icon {
  font-size: 5rem;
  color: var(--color-gold);
  font-weight: 300;
}

.product-tag {
  display: inline-block;
  font-family: var(--font-en);
  font-size: 0.7rem;
  color: var(--color-gold);
  letter-spacing: 0.2em;
  margin-bottom: 0.8rem;
  padding: 0.2rem 0.6rem;
  border: 1px solid var(--color-border-bright);
  border-radius: 2px;
}

.product-card h3 {
  font-size: 1.3rem;
  color: var(--color-text);
  margin-bottom: 0.4rem;
  font-weight: 500;
  letter-spacing: 0.05em;
  font-family: var(--font-en);
}
.product-card > p {
  font-size: 0.9rem;
  color: var(--color-text-2);
  margin-bottom: 1rem;
}

.product-features-label {
  font-size: 0.7rem;
  color: var(--color-accent, #B8902C);
  letter-spacing: 0.18em;
  text-transform: uppercase;
  font-weight: 600;
  margin-bottom: 0.4rem;
  margin-top: -0.2rem;
}
.product-features {
  list-style: none;
  font-size: 0.8rem;
  color: var(--color-text-3);
}
.product-features li {
  padding: 0.3rem 0;
  border-top: 1px solid rgba(255,255,255,0.05);
  letter-spacing: 0.03em;
}
.product-features li:first-child {
  border-top: none;
}

/* ============================================
   应用场景
   ============================================ */
.section-apps {
  background: var(--color-bg-2);
}

.apps-grid {
  display: grid;
  grid-template-columns: repeat(6, 1fr);
  gap: 1rem;
}

.app-item {
  padding: 1.5rem 1rem;
  background: var(--color-bg-3);
  border: 1px solid var(--color-border);
  text-align: center;
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--color-text-2);
  border-radius: 4px;
  transition: all 0.3s;
  cursor: default;
}
.app-item:hover {
  border-color: var(--color-gold);
  color: var(--color-gold-bright);
  background: rgba(184, 144, 44, 0.05);
  transform: translateY(-2px);
}

/* ============================================
   联系
   ============================================ */
.section-contact {
  background: linear-gradient(180deg, var(--color-bg-2) 0%, var(--color-bg) 100%);
}

.contact-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2rem;
  margin-top: 2rem;
}

.contact-item {
  padding: 2.5rem 2rem;
  background: var(--color-bg-3);
  border: 1px solid var(--color-border);
  border-radius: 4px;
  transition: all 0.3s;
}
.contact-item:hover {
  border-color: var(--color-border-bright);
  transform: translateY(-4px);
}

.contact-label {
  font-family: var(--font-en);
  font-size: 0.75rem;
  color: var(--color-gold);
  letter-spacing: 0.3em;
  margin-bottom: 1rem;
}
.contact-value {
  font-size: 1.5rem;
  color: var(--color-text);
  margin-bottom: 0.8rem;
  font-weight: 500;
  letter-spacing: 0.05em;
}
.contact-sub {
  font-size: 0.9rem;
  color: var(--color-text-3);
}
/* 第二个联系电话（董先生）与上一组拉开间距 */
.contact-extra {
  margin-top: 0.9rem;
}
.contact-link {
  display: inline-block;
  margin-top: 0.5rem;
  color: var(--color-gold);
  text-decoration: none;
  font-size: 0.9rem;
  letter-spacing: 0.05em;
  transition: letter-spacing 0.3s;
}
.contact-link:hover {
  letter-spacing: 0.1em;
}

/* 公司地址 · 点击跳转百度地图（09-07 新增） */
.map-link {
  color: var(--color-gold);
  text-decoration: none;
  border-bottom: 1px solid var(--color-border-bright);
  padding-bottom: 1px;
  transition: color 0.3s, border-color 0.3s;
}
.map-link:hover {
  color: var(--color-gold-bright);
  border-bottom-color: var(--color-gold-bright);
}

/* ============================================
   页脚
   ============================================ */
.footer {
  background: var(--color-bg);
  border-top: 1px solid var(--color-border);
  padding: 3rem 4rem;
}

.footer-inner {
  max-width: 1280px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 2rem;
}

.footer-logo {
  font-size: 1.2rem;
  font-weight: 500;
  color: var(--color-gold);
  letter-spacing: 0.15em;
  margin-bottom: 0.5rem;
}
.footer-tag {
  font-size: 0.85rem;
  color: var(--color-text-3);
}

.footer-right {
  text-align: right;
  font-size: 0.85rem;
  color: var(--color-text-3);
  line-height: 1.8;
}
.footer-beian {
  font-family: var(--font-en);
  font-size: 0.75rem;
}

/* ============================================
   响应式
   ============================================ */
@media (max-width: 1024px) {
  .arch-grid { grid-template-columns: 1fr; }
  .products-grid { grid-template-columns: repeat(2, 1fr); }
  .products-grid-4 { grid-template-columns: repeat(2, 1fr); }
  .contact-grid { grid-template-columns: 1fr; }
  .apps-grid { grid-template-columns: repeat(4, 1fr); }
}

@media (max-width: 768px) {
  .nav { padding: 1rem 1.5rem; }
  .nav-menu { gap: 1.2rem; }
  .nav-menu a { font-size: 0.8rem; }
  .section { padding: 4rem 1.5rem; min-height: auto; }
  .section-title { font-size: 2rem; }
  .hero-title { font-size: 3rem; letter-spacing: 0.2em; }
  .hero-subtitle { font-size: 1.1rem; }
  .hero-desc { font-size: 0.9rem; }
  .products-grid { grid-template-columns: 1fr; }
  .apps-grid { grid-template-columns: repeat(3, 1fr); }
  .footer-inner { flex-direction: column; text-align: center; }
  .footer-right { text-align: center; }
}

@media (max-width: 480px) {
  .nav-menu { gap: 0.8rem; }
  .nav-menu a { font-size: 0.75rem; }
  .logo-en { display: none; }
}

/* ============================================
   视频背景（SpaceX 滚动风）
   ============================================ */
.section-with-video {
  position: relative;
  overflow: hidden;
}

.bg-video {
  position: absolute;
  top: 50%;
  left: 50%;
  min-width: 100%;
  min-height: 100%;
  width: auto;
  height: auto;
  transform: translate(-50%, -50%);
  object-fit: cover;
  z-index: 0;
  opacity: 0.45;
  filter: brightness(0.55) contrast(1.1) saturate(0.9);
}

.video-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(
    180deg,
    rgba(0, 0, 0, 0.55) 0%,
    rgba(0, 0, 0, 0.7) 100%
  );
  z-index: 1;
  pointer-events: none;
}

.section-with-video .section-inner,
.section-with-video .hero-content {
  position: relative;
  z-index: 2;
}

/* 移动端视频降低不透明度避免性能问题 */
@media (max-width: 768px) {
  .bg-video {
    opacity: 0.35;
  }
}

/* ============================================
   Logo 图片（用 logo 替代文字，叶总 09-01 要求）
   ============================================ */
.nav-logo-img {
  height: 28px;
  width: auto;
  display: block;
}

.hero-logo { margin-bottom: 1.2rem; }
.hero-logo-img {
  height: 38px;
  width: auto;
  max-width: 100%;
  filter: drop-shadow(0 0 34px rgba(184, 144, 44, 0.5));
}

@media (max-width: 768px) {
  .nav-logo-img { height: 22px; }
  .hero-logo-img { height: 24px; }
}


/* ============================================
   雷达目标亮点（模拟真实雷达扫到目标）
   ============================================ */
.hero-blips {
  position: absolute;
  inset: 0;
  pointer-events: none;
  z-index: 1;
  overflow: hidden;
}

.radar-blip {
  position: absolute;
  width: 7px;
  height: 7px;
  margin: -3.5px 0 0 -3.5px;
  border-radius: 50%;
  background: rgba(255, 236, 168, 0.95);
  box-shadow: 0 0 16px 4px rgba(255, 220, 130, 0.85);
  opacity: 0;
  animation: blip-flash 8s linear infinite;
}

@keyframes blip-flash {
  0%   { opacity: 0;    transform: scale(0.4); }
  3%   { opacity: 1;    transform: scale(1.5); }
  7%   { opacity: 0.9;  transform: scale(1); }
  18%  { opacity: 0.5;  transform: scale(0.9); }
  34%  { opacity: 0;    transform: scale(0.7); }
  100% { opacity: 0;    transform: scale(0.7); }
}

/* ============================================
   产品卡片链接：去掉浏览器默认蓝色 + 下划线
   ============================================ */
a.product-card,
a.product-card:link,
a.product-card:visited,
a.product-card:hover,
a.product-card:focus,
a.product-card:active {
  color: inherit;
  text-decoration: none;
}
a.product-card * {
  text-decoration: none;
}


/* ============================================
   页脚 Logo 图片（叶总 09-02 要求）
   ============================================ */
.footer-logo-img {
  display: block;
  height: auto;
  margin-bottom: 0.45rem;
  max-width: 260px;   /* CSS 兜底：JS 不执行时也不会撑满容器 */
  width: auto;
}


/* ============================================
   产品中心改版（叶总 09-05 要求）
   1) 首页 4 款下方"浏览所有产品"按钮容器
   2) 全部产品总览页：顶部留白 + 三类筛选导航
   ============================================ */
.products-more {
  display: flex;
  justify-content: center;
  margin-top: 2.5rem;
}

.section-allproducts {
  padding-top: 9rem;
  background: var(--color-bg);
}

.cat-nav {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 1rem;
  margin: 2rem 0 2.5rem;
}
.cat-btn {
  padding: 0.55rem 1.4rem;
  border: 1px solid rgba(255, 255, 255, 0.28);
  background: transparent;
  color: var(--color-text-2);
  font-family: inherit;
  font-size: 0.8rem;
  letter-spacing: 0.06em;
  border-radius: 2px;
  cursor: pointer;
  transition: all 0.35s var(--ease-out);
}
.cat-btn:hover,
.cat-btn:focus-visible {
  border-color: rgba(255, 255, 255, 0.65);
  color: #fff;
  outline: none;
}
.cat-btn.active {
  border-color: var(--color-gold);
  color: var(--color-gold);
  background: rgba(184, 144, 44, 0.08);
}

@media (max-width: 768px) {
  .section-allproducts { padding-top: 6rem; }
  .cat-btn { font-size: 0.75rem; padding: 0.5rem 1rem; }
}