/* ============================================
   军华钢结构 - v8 圆角卡片风格
   配色：深蓝导航 / 橙色点缀 / 白色内容区
   断点：320 / 768 / 1024 / 1440 (mobile-first)
   ============================================ */

:root {
  --primary: #1b2f4b;
  --primary-dark: #122038;
  --accent: #e8722c;
  --accent-dark: #d05f1f;
  --bg: #f5f6f8;
  --bg-light: #ffffff;
  --text: #2b2f36;
  --text-light: #6b7280;
  --line: #e5e7eb;
  --radius: 14px;           /* v8 大圆角 */
  --radius-sm: 8px;
  --shadow: 0 4px 16px rgba(0,0,0,.06);
  --shadow-hover: 0 10px 28px rgba(0,0,0,.12);
  --container: 1200px;
}

* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  font-family: "Microsoft YaHei", "PingFang SC", "Helvetica Neue", Arial, sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.6;
}
img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
ul { list-style: none; }

.container {
  width: 100%;
  padding: 0 16px;
  margin: 0 auto;
  max-width: var(--container);
}

/* ---------- 顶部栏 ---------- */
.topbar { background: var(--primary-dark); color: #cfd6e0; font-size: 12px; display: none; }
.topbar-inner { display: flex; justify-content: space-between; align-items: center; height: 36px; }
.topbar-phone a { color: var(--accent); font-weight: 700; }

/* ---------- 头部导航 ---------- */
.header {
  background: var(--primary);
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: 0 2px 10px rgba(0,0,0,.18);
}
.header-inner { display: flex; align-items: center; justify-content: space-between; height: 64px; }
.logo a { display: flex; align-items: center; gap: 10px; }
.logo-mark {
  background: var(--accent);
  color: #fff;
  font-size: 20px;
  font-weight: 700;
  padding: 4px 10px;
  border-radius: var(--radius-sm);
  letter-spacing: 2px;
}
.logo-text { color: #fff; font-size: 18px; font-weight: 700; line-height: 1.2; display: flex; flex-direction: column; }
.logo-text small { font-size: 10px; font-weight: 400; color: #9fb0c4; letter-spacing: 1px; }

.nav-toggle { display: flex; flex-direction: column; gap: 5px; background: none; border: none; cursor: pointer; padding: 6px; }
.nav-toggle span { width: 24px; height: 2px; background: #fff; border-radius: 2px; transition: .3s; }

.nav {
  display: none;
  position: absolute;
  top: 64px;
  left: 0;
  right: 0;
  background: var(--primary);
  border-top: 1px solid rgba(255,255,255,.08);
}
.nav.open { display: block; }
.nav ul { flex-direction: column; }
.nav li a {
  display: block;
  color: #e6ebf2;
  padding: 14px 24px;
  border-bottom: 1px solid rgba(255,255,255,.06);
  font-size: 15px;
}
.nav li a:hover, .nav li a.active { color: var(--accent); }

/* ---------- 首屏 Banner ---------- */
.hero {
  background:
    linear-gradient(rgba(18,32,56,.72), rgba(18,32,56,.82)),
    url("../images/hero-bg.jpg") center/cover no-repeat,
    var(--primary-dark);
  color: #fff;
  padding: 72px 0;
  text-align: center;
}
.hero h1 { font-size: 28px; font-weight: 700; margin-bottom: 16px; letter-spacing: 1px; }
.hero p { font-size: 15px; color: #d7dee8; max-width: 640px; margin: 0 auto 28px; }
.hero-actions { display: flex; flex-direction: column; gap: 12px; align-items: center; }

.btn { display: inline-block; padding: 13px 30px; border-radius: 999px; font-size: 15px; font-weight: 700; transition: .2s; }
.btn-primary { background: var(--accent); color: #fff; box-shadow: 0 4px 14px rgba(232,114,44,.35); }
.btn-primary:hover { background: var(--accent-dark); transform: translateY(-2px); }
.btn-outline { border: 2px solid #fff; color: #fff; }
.btn-outline:hover { background: rgba(255,255,255,.12); }

/* ---------- 通用 section ---------- */
.section { padding: 48px 0; }
.section-head { text-align: center; margin-bottom: 32px; }
.section-head h2 { font-size: 24px; color: var(--primary); margin-bottom: 8px; position: relative; }
.section-head h2::after {
  content: "";
  display: block;
  width: 48px;
  height: 3px;
  background: var(--accent);
  margin: 12px auto 0;
  border-radius: 2px;
}
.section-head p { color: var(--text-light); font-size: 14px; }
.section-head.light h2 { color: #fff; }
.section-head.light p { color: #c3ccd8; }

/* ---------- 内页 Banner ---------- */
.page-hero {
  background:
    linear-gradient(rgba(18,32,56,.78), rgba(18,32,56,.86)),
    url("../images/hero-bg.jpg") center/cover no-repeat,
    var(--primary-dark);
  color: #fff;
  text-align: center;
  padding: 56px 0;
}
.page-hero h1 { font-size: 26px; font-weight: 700; margin-bottom: 8px; }
.page-hero p { font-size: 14px; color: #d7dee8; }

/* ---------- 公司介绍内容 ---------- */
.about-content { max-width: 860px; }
.about-content h2 {
  font-size: 20px;
  color: var(--primary);
  margin: 32px 0 12px;
  padding-left: 14px;
  border-left: 4px solid var(--accent);
}
.about-content h2:first-child { margin-top: 0; }
.about-content p {
  font-size: 15px;
  color: var(--text);
  line-height: 2;
  text-indent: 2em;
  margin-bottom: 8px;
}

/* ---------- 产品展示（v8 圆角卡片） ---------- */
.product-grid { display: grid; gap: 20px; grid-template-columns: 1fr; }
.product-card {
  background: var(--bg-light);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  overflow: hidden;
  transition: .25s;
  border: 1px solid var(--line);
}
.product-card:hover { transform: translateY(-6px); box-shadow: var(--shadow-hover); }
.product-img { position: relative; overflow: hidden; }
.product-img img { width: 100%; height: 200px; object-fit: cover; transition: .35s; }
.product-card:hover .product-img img { transform: scale(1.05); }
.product-img .tag {
  position: absolute;
  top: 12px;
  left: 12px;
  background: var(--accent);
  color: #fff;
  font-size: 13px;
  font-weight: 700;
  padding: 4px 14px;
  border-radius: 999px;
  box-shadow: 0 2px 8px rgba(0,0,0,.2);
}
.product-body { padding: 18px 20px 20px; }
.product-body h3 { font-size: 18px; color: var(--primary); margin-bottom: 8px; }
.product-body p { font-size: 13px; color: var(--text-light); margin-bottom: 12px; }
.card-link { color: var(--accent); font-size: 14px; font-weight: 700; }
.card-link:hover { color: var(--accent-dark); }

/* ---------- 产品展示（v8 圆角卡片） ---------- */
.product-grid-lg .product-card { display: flex; flex-direction: column; }
@media (min-width: 1024px) {
  .product-grid-lg .product-card {
    flex-direction: row;
    align-items: stretch;
  }
  .product-grid-lg .product-img { width: 42%; flex-shrink: 0; }
  .product-grid-lg .product-img img { height: 100%; }
  .product-grid-lg .product-body { flex: 1; display: flex; flex-direction: column; }
  .product-grid-lg .product-body .btn { margin-top: auto; align-self: flex-start; }
}
.prod-points {
  margin: 8px 0 16px;
  padding-left: 0;
}
.prod-points li {
  font-size: 13px;
  color: var(--text-light);
  padding: 3px 0 3px 18px;
  position: relative;
}
.prod-points li::before {
  content: "";
  position: absolute;
  left: 2px;
  top: 10px;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--accent);
}
.btn-sm { padding: 9px 22px; font-size: 14px; }
.product-grid-lg { gap: 24px; }

/* ---------- 公司优势 ---------- */
.advantage { background: var(--primary); }
.adv-grid { display: grid; gap: 16px; grid-template-columns: repeat(2, 1fr); }
.adv-item {
  background: rgba(255,255,255,.06);
  border: 1px solid rgba(255,255,255,.12);
  border-radius: var(--radius);
  text-align: center;
  padding: 26px 12px;
}
.adv-item b { display: block; font-size: 20px; color: var(--accent); margin-bottom: 4px; }
.adv-item span { color: #e6ebf2; font-size: 14px; }

/* ---------- 工程案例 ---------- */
.case-grid { display: grid; gap: 16px; grid-template-columns: 1fr; }
.case-item {
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow);
}
.case-item img { width: 100%; height: 200px; object-fit: cover; transition: .35s; }
.case-item:hover img { transform: scale(1.06); }
.case-item-txt { position: relative; }
.case-overlay {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  padding: 28px 16px 12px;
  background: linear-gradient(transparent, rgba(18,32,56,.88));
  color: #fff;
}
.case-overlay h3 { font-size: 16px; font-weight: 700; margin-bottom: 2px; }
.case-overlay p { font-size: 12px; color: #d7dee8; }

/* ---------- 成单流程 ---------- */
.process-steps { display: grid; gap: 16px; grid-template-columns: 1fr; }
.step {
  background: var(--bg-light);
  border-radius: var(--radius);
  border: 1px solid var(--line);
  padding: 22px 18px;
  box-shadow: var(--shadow);
  text-align: center;
}
.step b { display: inline-block; font-size: 28px; color: var(--accent); margin-bottom: 8px; }
.step span { display: block; font-size: 16px; font-weight: 700; color: var(--primary); margin-bottom: 6px; }
.step p { font-size: 13px; color: var(--text-light); }

/* ---------- 新闻 ---------- */
.news-list {
  background: var(--bg-light);
  border-radius: var(--radius);
  border: 1px solid var(--line);
  box-shadow: var(--shadow);
  overflow: hidden;
}
.news-list-lg .news-item { padding: 18px 20px; }
.news-list-lg .news-item a { font-size: 15px; }
.news-list-lg .news-date { font-size: 13px; }
@media (min-width: 1024px) {
  .news-list-lg {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
    background: transparent;
    border: none;
    box-shadow: none;
    overflow: visible;
  }
  .news-list-lg .news-item {
    background: var(--bg-light);
    border: 1px solid var(--line);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    gap: 8px;
    padding: 20px;
    transition: .25s;
  }
  .news-list-lg .news-item:hover {
    box-shadow: var(--shadow-hover);
    transform: translateY(-3px);
  }
  .news-list-lg .news-item a {
    font-size: 15px;
    font-weight: 700;
    color: var(--primary);
    line-height: 1.5;
  }
  .news-list-lg .news-item a:hover { color: var(--accent); }
}
.news-item {
  display: flex;
  gap: 12px;
  align-items: center;
  padding: 14px 16px;
  border-bottom: 1px solid var(--line);
  font-size: 14px;
}
.news-item:last-child { border-bottom: none; }
.news-item a { color: var(--text); flex: 1; }
.news-item a:hover { color: var(--accent); }
.news-date {
  background: var(--primary);
  color: #fff;
  font-size: 12px;
  border-radius: 999px;
  padding: 2px 10px;
  flex-shrink: 0;
}

/* ---------- 联系我们 ---------- */
.contact { background: var(--primary); }
.contact-grid { display: grid; gap: 16px; grid-template-columns: 1fr; }
.contact-item {
  background: rgba(255,255,255,.06);
  border: 1px solid rgba(255,255,255,.12);
  border-radius: var(--radius);
  padding: 18px 20px;
}
.contact-item span { display: block; font-size: 12px; color: #9fb0c4; margin-bottom: 4px; }
.contact-item b { color: #fff; font-size: 15px; }
.contact-item b a { color: var(--accent); }

/* ---------- 联系信息卡片 ---------- */
.contact-info {
  display: grid;
  gap: 16px;
  grid-template-columns: 1fr;
  margin-bottom: 40px;
}
.contact-info-card {
  background: var(--bg-light);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 24px;
  display: flex;
  align-items: flex-start;
  gap: 16px;
  transition: .25s;
}
.contact-info-card:hover { box-shadow: var(--shadow-hover); transform: translateY(-3px); }
.ci-icon {
  font-size: 32px;
  line-height: 1;
  flex-shrink: 0;
  background: rgba(232,114,44,.12);
  border-radius: var(--radius-sm);
  padding: 10px;
}
.contact-info-card h3 {
  font-size: 15px;
  color: var(--primary);
  margin-bottom: 6px;
}
.contact-info-card p { font-size: 15px; color: var(--text); }
.contact-info-card p a { color: var(--accent); font-weight: 700; }
.contact-cta {
  text-align: center;
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  border-radius: var(--radius);
  padding: 48px 24px;
  color: #fff;
}
.contact-cta h2 { font-size: 22px; margin-bottom: 8px; }
.contact-cta p { color: #c3ccd8; margin-bottom: 24px; font-size: 14px; }
@media (min-width: 768px) {
  .contact-info { grid-template-columns: repeat(2, 1fr); }
  .contact-cta { padding: 56px 32px; }
}
@media (min-width: 1024px) {
  .contact-info { grid-template-columns: repeat(2, 1fr); }
}

/* ---------- 页脚 ---------- */
.footer { background: var(--primary-dark); color: #9fb0c4; text-align: center; padding: 24px 0; font-size: 12px; }
.footer-inner p { margin: 4px 0; }

/* ============================================
   响应式断点
   ============================================ */

/* ≥768px 平板 */
@media (min-width: 768px) {
  .topbar { display: block; }
  .hero { padding: 96px 0; }
  .hero h1 { font-size: 36px; }
  .hero-actions { flex-direction: row; justify-content: center; }
  .product-grid { grid-template-columns: repeat(3, 1fr); }
  .adv-grid { grid-template-columns: repeat(4, 1fr); }
  .case-grid { grid-template-columns: repeat(2, 1fr); }
  .process-steps { grid-template-columns: repeat(4, 1fr); }
  .contact-grid { grid-template-columns: repeat(2, 1fr); }
  .section { padding: 64px 0; }
}

/* ≥1024px 桌面 */
@media (min-width: 1024px) {
  .nav-toggle { display: none; }
  .nav { display: block; position: static; border-top: none; background: transparent; }
  .nav ul { display: flex; flex-direction: row; gap: 28px; }
  .nav li a { padding: 0; border: none; font-size: 15px; }
  .case-grid { grid-template-columns: repeat(3, 1fr); }
  .container { padding: 0 24px; }
}

/* ≥1440px 大屏 */
@media (min-width: 1440px) {
  .container { padding: 0 32px; }
  .hero h1 { font-size: 42px; }
}