/* ===== 品那高 (北京) 安全科技服务有限公司 官网样式 ===== */

:root {
  --primary: #1a3a5c;
  --primary-dark: #0f2440;
  --accent: #e8492e;
  --accent-hover: #c9351f;
  --text: #333;
  --text-light: #666;
  --bg-light: #f8f9fa;
  --bg-white: #fff;
  --border: #e0e0e0;
  --shadow: 0 2px 12px rgba(0,0,0,0.08);
  --shadow-lg: 0 8px 30px rgba(0,0,0,0.12);
  --radius: 8px;
  --max-width: 1200px;
  --header-height: 72px;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
  color: var(--text);
  line-height: 1.6;
  background: var(--bg-white);
}

a {
  color: var(--primary);
  text-decoration: none;
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

/* ===== Header ===== */
.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: rgba(255,255,255,0.95);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
  height: var(--header-height);
  transition: box-shadow 0.3s;
}

.header.scrolled {
  box-shadow: var(--shadow);
}

.header-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.logo {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 20px;
  font-weight: 700;
  color: var(--primary);
}

.logo img {
  height: 40px;
}

.logo span {
  letter-spacing: 1px;
}

.nav {
  display: flex;
  align-items: center;
  gap: 4px;
}

.nav a {
  display: block;
  padding: 8px 16px;
  border-radius: 6px;
  color: var(--text);
  font-size: 15px;
  transition: all 0.2s;
  white-space: nowrap;
}

.nav a:hover,
.nav a.active {
  color: var(--accent);
  background: rgba(232, 73, 46, 0.06);
}

.nav-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
  flex-direction: column;
  gap: 5px;
}

.nav-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--primary);
  transition: all 0.3s;
}

/* ===== Hero Section ===== */
.hero {
  margin-top: var(--header-height);
  position: relative;
  height: 75vh;
  min-height: 500px;
  overflow: hidden;
  background: #000;
}

.hero video {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  min-width: 100%;
  min-height: 100%;
  width: auto;
  height: auto;
  object-fit: cover;
  opacity: 0.7;
}

.hero-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(15,36,64,0.85) 0%, rgba(15,36,64,0.4) 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 40px;
}

.hero-content {
  max-width: 800px;
  color: #fff;
}

.hero-content h1 {
  font-size: 48px;
  font-weight: 700;
  line-height: 1.3;
  margin-bottom: 20px;
  letter-spacing: 2px;
}

.hero-content p {
  font-size: 20px;
  opacity: 0.9;
  margin-bottom: 36px;
  line-height: 1.8;
}

.hero-buttons {
  display: flex;
  gap: 16px;
  justify-content: center;
  flex-wrap: wrap;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 32px;
  border-radius: 50px;
  font-size: 16px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s;
  border: 2px solid transparent;
}

.btn-primary {
  background: var(--accent);
  color: #fff;
}

.btn-primary:hover {
  background: var(--accent-hover);
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(232, 73, 46, 0.4);
}

.btn-outline {
  background: transparent;
  color: #fff;
  border-color: rgba(255,255,255,0.5);
}

.btn-outline:hover {
  border-color: #fff;
  background: rgba(255,255,255,0.1);
  transform: translateY(-2px);
}

/* ===== Sections ===== */
.section {
  padding: 80px 24px;
}

.section-dark {
  background: var(--bg-light);
}

.section-inner {
  max-width: var(--max-width);
  margin: 0 auto;
}

.section-header {
  text-align: center;
  margin-bottom: 60px;
}

.section-header h2 {
  font-size: 36px;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 12px;
}

.section-header p {
  font-size: 18px;
  color: var(--text-light);
  max-width: 600px;
  margin: 0 auto;
}

/* ===== Page Banner ===== */
.page-banner {
  margin-top: var(--header-height);
  height: 40vh;
  min-height: 300px;
  position: relative;
  overflow: hidden;
  background: var(--primary-dark);
  display: flex;
  align-items: center;
  justify-content: center;
}

.page-banner img,
.page-banner video {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.5;
}

.page-banner-content {
  position: relative;
  z-index: 1;
  text-align: center;
  color: #fff;
}

.page-banner-content h1 {
  font-size: 42px;
  font-weight: 700;
  margin-bottom: 12px;
}

.page-banner-content p {
  font-size: 18px;
  opacity: 0.85;
}

/* ===== Card Grid ===== */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 28px;
}

.card {
  background: var(--bg-white);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow);
  transition: all 0.3s;
  border: 1px solid var(--border);
}

.card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}

.card-image {
  width: 100%;
  height: 200px;
  object-fit: cover;
  background: var(--bg-light);
}

.card-body {
  padding: 24px;
}

.card-body h3 {
  font-size: 20px;
  color: var(--primary);
  margin-bottom: 8px;
}

.card-body p {
  color: var(--text-light);
  font-size: 15px;
  line-height: 1.7;
}

/* ===== Capability Cards ===== */
.capability-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 40px;
  align-items: center;
}

.capability-item {
  display: flex;
  gap: 32px;
  align-items: flex-start;
}

.capability-item .capability-image {
  flex-shrink: 0;
  width: 160px;
  height: 160px;
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow);
}

.capability-item .capability-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.capability-item .capability-text h3 {
  font-size: 22px;
  color: var(--primary);
  margin-bottom: 8px;
}

.capability-item .capability-text p {
  color: var(--text-light);
  font-size: 15px;
  line-height: 1.8;
}

.capability-sub-images {
  display: flex;
  gap: 8px;
  margin-top: 16px;
}

.capability-sub-images img {
  width: 80px;
  height: 60px;
  object-fit: cover;
  border-radius: 4px;
}

/* ===== Product Categories ===== */
.product-category {
  margin-bottom: 48px;
}

.product-category h3 {
  font-size: 24px;
  color: var(--primary);
  margin-bottom: 20px;
  padding-bottom: 8px;
  border-bottom: 3px solid var(--accent);
  display: inline-block;
}

.product-list {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
  gap: 20px;
}

.product-card {
  background: var(--bg-white);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 0;
  text-align: center;
  transition: all 0.3s;
  overflow: hidden;
}

.product-card:hover {
  box-shadow: var(--shadow-lg);
  border-color: var(--accent);
  transform: translateY(-3px);
}

.product-card .product-img-wrap {
  background: linear-gradient(135deg, #f5f5f5 0%, #e8e8e8 100%);
  padding: 20px;
  display: flex;
  align-items: center;
  justify-content: center;
  height: 180px;
}

.product-card .product-img-wrap img {
  max-width: 100%;
  max-height: 140px;
  object-fit: contain;
  transition: transform 0.3s;
}

.product-card:hover .product-img-wrap img {
  transform: scale(1.05);
}

.product-card .product-info {
  padding: 16px 20px 20px;
}

.product-card h4 {
  font-size: 16px;
  color: var(--primary);
  margin-bottom: 6px;
}

.product-card p {
  font-size: 13px;
  color: var(--text-light);
  line-height: 1.6;
}

.product-card h4 {
  font-size: 16px;
  color: var(--primary);
  margin-bottom: 8px;
}

.product-card p {
  font-size: 13px;
  color: var(--text-light);
  line-height: 1.6;
}

/* ===== Case Cards ===== */
.case-card {
  background: var(--bg-white);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow);
  border: 1px solid var(--border);
  margin-bottom: 32px;
  transition: all 0.3s;
}

.case-card:hover {
  box-shadow: var(--shadow-lg);
}

.case-card .case-image {
  width: 100%;
  height: 280px;
  object-fit: cover;
}

.case-card .case-body {
  padding: 28px;
}

.case-card .case-body h3 {
  font-size: 22px;
  color: var(--primary);
  margin-bottom: 12px;
}

.case-card .case-body p {
  color: var(--text-light);
  line-height: 1.9;
  font-size: 15px;
}

/* ===== About Page ===== */
.about-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
  align-items: start;
}

.about-image {
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow-lg);
}

.about-text h3 {
  font-size: 24px;
  color: var(--primary);
  margin-bottom: 16px;
}

.about-text p {
  color: var(--text-light);
  line-height: 1.9;
  margin-bottom: 16px;
}

.values {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
  margin-top: 24px;
}

.value-item {
  background: var(--bg-light);
  padding: 20px;
  border-radius: var(--radius);
  text-align: center;
}

.value-item h4 {
  color: var(--primary);
  margin-bottom: 4px;
}

.value-item p {
  font-size: 14px;
  color: var(--text-light);
  margin: 0;
}

/* ===== Advantages ===== */
.advantages {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  text-align: center;
}

.advantage-item {
  padding: 32px 20px;
}

.advantage-item .adv-icon {
  width: 80px;
  height: 80px;
  margin: 0 auto 16px;
  background: var(--bg-light);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 32px;
}

.advantage-item h4 {
  color: var(--primary);
  margin-bottom: 8px;
}

.advantage-item p {
  color: var(--text-light);
  font-size: 14px;
}

/* ===== Footer ===== */
.footer {
  background: var(--primary-dark);
  color: rgba(255,255,255,0.7);
  padding: 48px 24px 24px;
}

.footer-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: 40px;
}

.footer h4 {
  color: #fff;
  margin-bottom: 16px;
  font-size: 16px;
}

.footer p, .footer a {
  font-size: 14px;
  line-height: 2;
}

.footer a {
  color: rgba(255,255,255,0.7);
  transition: color 0.2s;
}

.footer a:hover {
  color: #fff;
}

.footer-bottom {
  max-width: var(--max-width);
  margin: 32px auto 0;
  padding-top: 20px;
  border-top: 1px solid rgba(255,255,255,0.1);
  text-align: center;
  font-size: 13px;
}

/* ===== Responsive ===== */
@media (max-width: 768px) {
  .hero-content h1 {
    font-size: 32px;
  }

  .hero-content p {
    font-size: 16px;
  }

  .nav {
    display: none;
    position: absolute;
    top: var(--header-height);
    left: 0;
    right: 0;
    background: var(--bg-white);
    flex-direction: column;
    padding: 16px;
    box-shadow: var(--shadow);
  }

  .nav.open {
    display: flex;
  }

  .nav-toggle {
    display: flex;
  }

  .capability-grid {
    grid-template-columns: 1fr;
    gap: 24px;
  }

  .capability-item {
    flex-direction: column;
    gap: 16px;
  }

  .advantages {
    grid-template-columns: repeat(2, 1fr);
  }

  .about-grid {
    grid-template-columns: 1fr;
  }

  .footer-inner {
    grid-template-columns: 1fr;
    gap: 24px;
  }

  .hero-buttons {
    flex-direction: column;
    align-items: center;
  }
}

@media (max-width: 480px) {
  .section {
    padding: 48px 16px;
  }

  .section-header h2 {
    font-size: 28px;
  }

  .advantages {
    grid-template-columns: 1fr;
  }

  .card-grid {
    grid-template-columns: 1fr;
  }
}