/* ===========================
   全局变量与重置
   =========================== */
:root {
  --red: #e40b0b;
  --dark-red: #c41212;
  --dark: #071027;
  --dark2: #0a1230;
  --text: #333333;
  --text-light: #ffffff;
  --gray: #f5f5f5;
  --container: 1200px;
  --header-h: 72px;
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: var(--header-h);
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Helvetica Neue", Arial, sans-serif;
  color: var(--text);
  background: #fff;
  line-height: 1.7;
  overflow-x: hidden;
}

a { text-decoration: none; color: inherit; }
ul { list-style: none; }

.container {
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 24px;
}

.section { padding: 90px 0; }

/* ===========================
   导航栏
   =========================== */
.header {
  position: fixed;
  top: 0; left: 0;
  width: 100%;
  height: var(--header-h);
  background: rgba(7, 16, 39, 0.9);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  z-index: 1000;
  border-bottom: 2px solid var(--red);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

.logo {
  font-size: 20px;
  font-weight: 800;
  color: var(--text-light);
  letter-spacing: 1.5px;
  white-space: nowrap;
}

.nav-list { display: flex; gap: 34px; }

.nav-link {
  font-size: 14px;
  font-weight: 600;
  color: rgba(255, 255, 255, 0.85);
  letter-spacing: 0.5px;
  padding: 6px 0;
  position: relative;
  transition: color 0.3s;
}

.nav-link:hover,
.nav-link.active {
  color: var(--text-light);
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: 0; left: 0;
  width: 100%;
  height: 3px;
  background: var(--red);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.35s ease;
}

.nav-link:hover::after,
.nav-link.active::after { transform: scaleX(1); }

/* 汉堡菜单 */
.hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
  z-index: 1001;
}
.hamburger span {
  display: block;
  width: 26px; height: 2px;
  background: #fff;
  border-radius: 2px;
  transition: all 0.3s;
}
.hamburger.active span:nth-child(1) { transform: rotate(45deg) translate(5px, 5px); }
.hamburger.active span:nth-child(2) { opacity: 0; }
.hamburger.active span:nth-child(3) { transform: rotate(-45deg) translate(5px, -5px); }

/* ===========================
   Hero / 首屏
   =========================== */
.hero {
  position: relative;
  height: 100vh;
  min-height: 600px;
  background: linear-gradient(160deg, #1a1a2e 0%, #16213e 35%, #0f3460 65%, #7a0f0f 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background:
    radial-gradient(ellipse at 30% 60%, rgba(228, 11, 11, 0.18) 0%, transparent 55%),
    radial-gradient(ellipse at 75% 25%, rgba(255, 255, 255, 0.06) 0%, transparent 45%),
    repeating-linear-gradient(0deg, transparent, transparent 3px, rgba(255, 255, 255, 0.025) 3px, rgba(255, 255, 255, 0.025) 6px);
}

.hero-overlay {
  position: absolute;
  inset: 0;
  background: rgba(0, 0, 0, 0.3);
}

.hero-content {
  position: relative;
  z-index: 2;
  color: var(--text-light);
  padding: 0 24px;
}

.hero-title {
  font-size: clamp(30px, 5.5vw, 62px);
  font-weight: 800;
  letter-spacing: 4px;
  text-shadow: 0 3px 15px rgba(0, 0, 0, 0.5);
  animation: fadeUp 0.9s ease both;
}

.hero-subtitle {
  font-size: clamp(15px, 2.5vw, 21px);
  font-weight: 300;
  letter-spacing: 3px;
  margin: 22px 0 44px;
  color: rgba(255, 255, 255, 0.85);
  animation: fadeUp 0.9s ease 0.3s both;
}

.btn-hero {
  display: inline-block;
  padding: 14px 50px;
  border: 2px solid #fff;
  color: #fff;
  font-size: 14px;
  font-weight: 700;
  letter-spacing: 2px;
  transition: all 0.35s ease;
  animation: fadeUp 0.9s ease 0.6s both;
}
.btn-hero:hover {
  background: var(--red);
  border-color: var(--red);
  transform: translateY(-3px);
  box-shadow: 0 10px 30px rgba(228, 11, 11, 0.45);
}

@keyframes fadeUp {
  from { opacity: 0; transform: translateY(40px); }
  to   { opacity: 1; transform: translateY(0); }
}

/* ===========================
   区块标题
   =========================== */
.section-title {
  font-size: 30px;
  font-weight: 800;
  color: #222;
  letter-spacing: 1px;
  margin-bottom: 8px;
}

.section-title--light { color: var(--text-light); }
.section-title--center { text-align: center; margin-bottom: 50px; }

.section-subtitle {
  font-size: 14px;
  color: #888;
  letter-spacing: 2px;
  margin-bottom: 20px;
}

.title-underline {
  width: 56px;
  height: 3px;
  background: var(--red);
  margin-bottom: 28px;
}

/* ===========================
   About / 关于我们
   =========================== */
.about { background: #fff; }

.about-top {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
  margin-bottom: 70px;
}

.about-desc {
  font-size: 15px;
  color: #555;
  line-height: 2;
}

.about-images {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

.about-img {
  border-radius: 4px;
  overflow: hidden;
  transition: transform 0.4s ease;
  display: flex;
  align-items: center;
  justify-content: center;
}
.about-img:hover { transform: scale(1.02); }

.about-img-src {
  width: 100%;
  height: 100%;
  object-fit: contain;
  display: block;
}

.about-img--1 {
  aspect-ratio: 1;
  background: #ffffff;
}
.about-img--2 {
  aspect-ratio: 1;
  background:
    radial-gradient(ellipse at 60% 40%, rgba(228,11,11,0.25) 0%, transparent 50%),
    linear-gradient(135deg, #2e2e2e 0%, #505050 55%, #1f1f1f 100%);
}

/* 统计数字 */
.stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  background: var(--gray);
  border-top: 3px solid var(--red);
}

.stat-item {
  padding: 44px 16px;
  text-align: center;
  border-right: 1px solid #e4e4e4;
  transition: background 0.3s;
}
.stat-item:last-child { border-right: none; }
.stat-item:hover { background: #ececec; }

.stat-number {
  display: block;
  font-size: 44px;
  font-weight: 800;
  color: var(--red);
  line-height: 1.1;
}

.stat-plus { font-size: 24px; }

.stat-label {
  display: block;
  margin-top: 10px;
  font-size: 13px;
  color: #666;
  text-transform: uppercase;
  letter-spacing: 1px;
}

/* ===========================
   Products / 产品
   =========================== */
.products { background: var(--gray); }

.products-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 16px;
  margin-bottom: 10px;
}

.btn-view-more {
  display: inline-block;
  padding: 10px 34px;
  border: 2px solid var(--red);
  color: var(--red);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 1.5px;
  transition: all 0.35s ease;
}
.btn-view-more:hover {
  background: var(--red);
  color: #fff;
  box-shadow: 0 4px 18px rgba(228, 11, 11, 0.3);
}

.products-subtitle {
  font-size: 21px;
  font-weight: 700;
  color: #222;
  letter-spacing: 1px;
  margin-bottom: 40px;
}

.product-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 26px;
}

.product-card {
  background: #fff;
  border-radius: 4px;
  overflow: hidden;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.07);
  transition: transform 0.4s ease, box-shadow 0.4s ease;
}
.product-card:hover {
  transform: translateY(-8px);
  box-shadow: 0 14px 35px rgba(0, 0, 0, 0.14);
}

.product-img {
  aspect-ratio: 16 / 10;
  transition: transform 0.5s ease;
  overflow: hidden;
  display: flex;
  align-items: center;
  justify-content: center;
}
.product-card:hover .product-img { transform: scale(1.06); }

.product-img-src {
  max-width: 100%;
  max-height: 100%;
  width: auto;
  height: auto;
  object-fit: contain;
  display: block;
}

.product-img--1 { background: linear-gradient(135deg, #2c3e50 0%, #4a6b8a 60%, #2c3e50 100%); }
.product-img--2 { background: linear-gradient(135deg, #5d2e2e 0%, #9c4141 60%, #5d2e2e 100%); }
.product-img--3 { background: linear-gradient(135deg, #2e3d5d 0%, #4a5d8a 60%, #2e3d5d 100%); }
.product-img--4 { background: linear-gradient(135deg, #3a3a3a 0%, #666 60%, #333 100%); }

.product-info { padding: 18px 24px; }
.product-info h4 {
  font-size: 17px;
  font-weight: 700;
  color: #222;
  transition: color 0.3s;
}
.product-card:hover .product-info h4 { color: var(--red); }

/* ===========================
   Culture / 企业文化
   =========================== */
.culture {
  background: linear-gradient(150deg, var(--dark) 0%, var(--dark2) 100%);
  position: relative;
}

.culture::before {
  content: '';
  position: absolute;
  top: 0; left: 0;
  width: 100%; height: 4px;
  background: linear-gradient(90deg, var(--red), transparent 40%);
}

.culture .section-title {
  text-align: center;
  margin-bottom: 55px;
}

.culture-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 30px;
}

.culture-card {
  text-align: center;
  padding: 46px 26px;
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid rgba(255, 255, 255, 0.08);
  transition: all 0.4s ease;
}
.culture-card:hover {
  background: rgba(228, 11, 11, 0.08);
  border-color: rgba(228, 11, 11, 0.3);
  transform: translateY(-6px);
}

.culture-card-title {
  font-size: 22px;
  font-weight: 800;
  color: var(--text-light);
  letter-spacing: 2px;
  margin-bottom: 20px;
  position: relative;
  padding-bottom: 16px;
}
.culture-card-title::after {
  content: '';
  position: absolute;
  bottom: 0; left: 50%;
  transform: translateX(-50%);
  width: 36px; height: 3px;
  background: var(--red);
}

.culture-desc {
  font-size: 14px;
  color: rgba(255, 255, 255, 0.75);
  line-height: 2;
  letter-spacing: 0.5px;
}

/* ===========================
   News / 新闻
   =========================== */
.news { background: #fff; }

.news-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 30px;
}

.news-card {
  background: #fff;
  border-radius: 4px;
  overflow: hidden;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.07);
  transition: transform 0.4s ease, box-shadow 0.4s ease;
}
.news-card:hover {
  transform: translateY(-8px);
  box-shadow: 0 14px 35px rgba(0, 0, 0, 0.14);
}

.news-img {
  aspect-ratio: 16 / 10;
  transition: transform 0.5s ease;
}
.news-card:hover .news-img { transform: scale(1.05); }

.news-img--1 { background: linear-gradient(135deg, #4a5568 0%, #718096 60%, #4a5568 100%); }
.news-img--2 { background: linear-gradient(135deg, #3b4a5e 0%, #5d748f 60%, #3b4a5e 100%); }
.news-img--3 { background: linear-gradient(135deg, #5e3b3b 0%, #8f5d5d 60%, #5e3b3b 100%); }

.news-content { padding: 22px 24px; }

.news-date {
  font-size: 12px;
  color: #999;
}

.news-title {
  font-size: 16px;
  font-weight: 700;
  color: #222;
  margin: 8px 0 10px;
  line-height: 1.45;
  transition: color 0.3s;
}
.news-card:hover .news-title { color: var(--red); }

.news-excerpt {
  font-size: 13px;
  color: #777;
  line-height: 1.8;
  margin-bottom: 14px;
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.news-tag {
  display: inline-block;
  padding: 4px 12px;
  background: var(--red);
  color: #fff;
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 1px;
}

/* ===========================
   Contact / 联系我们
   =========================== */
.contact {
  background: linear-gradient(150deg, var(--dark) 0%, var(--dark2) 100%);
  position: relative;
}
.contact::before {
  content: '';
  position: absolute;
  top: 0; left: 0;
  width: 100%; height: 4px;
  background: linear-gradient(90deg, transparent 60%, var(--red));
}

.contact-info {
  max-width: 640px;
  margin: 0 auto;
}

.contact-item {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 14px;
  margin-bottom: 22px;
  color: rgba(255, 255, 255, 0.85);
}

.contact-label {
  font-size: 13px;
  font-weight: 700;
  color: var(--red);
  letter-spacing: 1px;
  text-transform: uppercase;
  flex-shrink: 0;
}

.contact-item p {
  font-size: 15px;
  letter-spacing: 0.5px;
}

/* ===========================
   Footer / 页脚
   =========================== */
.footer {
  background: #050a18;
  padding: 26px 0;
  text-align: center;
}

.footer-text {
  font-size: 13px;
  color: rgba(255, 255, 255, 0.45);
  letter-spacing: 0.5px;
}

/* ===========================
   响应式
   =========================== */
@media (max-width: 768px) {
  .section { padding: 65px 0; }

  .nav {
    position: fixed;
    top: 0; right: -100%;
    width: 280px;
    height: 100vh;
    background: var(--dark);
    padding: 100px 30px 40px;
    transition: right 0.4s ease;
    z-index: 999;
  }
  .nav.open { right: 0; }
  .nav-list { flex-direction: column; gap: 22px; }
  .hamburger { display: flex; }

  .about-top { grid-template-columns: 1fr; gap: 40px; }
  .stats { grid-template-columns: repeat(2, 1fr); }
  .stat-item:nth-child(2) { border-right: none; }
  .product-grid { grid-template-columns: 1fr 1fr; }
  .culture-grid { grid-template-columns: 1fr; }
  .news-grid { grid-template-columns: 1fr; }
}

@media (max-width: 480px) {
  .logo { font-size: 15px; }
  .section-title { font-size: 24px; }
  .hero-title { font-size: 24px; letter-spacing: 2px; }
  .stat-number { font-size: 32px; }
  .product-grid { grid-template-columns: 1fr; }
  .products-header { flex-direction: column; align-items: flex-start; }
  .contact-item { flex-direction: column; text-align: center; }
}