/* ============================================================
   xrn.cn - 武汉水泥制品官网
   高级亮蓝色商务风格
   ============================================================ */

/* ---- CSS Reset ---- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; scroll-padding-top: 80px; }
body {
  font-family: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", Helvetica, Arial, sans-serif;
  font-size: 16px; line-height: 1.7; color: #222;
  background: #ffffff; -webkit-font-smoothing: antialiased;
  -webkit-text-size-adjust: 100%;
}
img { max-width: 100%; height: auto; display: block; border: 0; }
a { color: inherit; text-decoration: none; transition: color .2s; }
a:hover { color: #0057b8; }
ul, ol { list-style: none; }
h1, h2, h3, h4, h5, h6 { font-weight: 700; line-height: 1.3; }
button { cursor: pointer; border: 0; background: none; font: inherit; }
figure { margin: 0; }
address { font-style: normal; }

/* ---- 配色变量 ---- */
:root {
  --blue-900: #003a8c;   /* 深蓝 */
  --blue-800: #0047a3;
  --blue-700: #0057b8;   /* 主色 */
  --blue-600: #0066cc;
  --blue-500: #0077e6;
  --blue-400: #3b92ee;
  --blue-300: #7ab4f5;
  --blue-100: #e8f1fc;
  --blue-50:  #f2f7fd;
  --navy:     #0b2545;
  --gold:     #d4a54b;
  --gray-900: #1a1a1a;
  --gray-700: #444;
  --gray-500: #888;
  --gray-300: #ddd;
  --gray-100: #f4f6f9;
  --white:    #ffffff;
  --shadow-sm: 0 2px 8px rgba(0,55,139,.08);
  --shadow-md: 0 6px 20px rgba(0,55,139,.10);
  --shadow-lg: 0 12px 40px rgba(0,55,139,.14);
}

.container { max-width: 1240px; margin: 0 auto; padding: 0 20px; }

/* ========== Emoji → SVG 图标替换后的颜色控制 ==========
   图标 fill="currentColor"，颜色由 color 属性控制
   这样任何系统/浏览器都一致，不再受 Windows Segoe UI Emoji 干扰
*/
.icon {
  display: inline-block;
  color: var(--blue-700);
  vertical-align: middle;
  transform: translateY(1px);
  line-height: 1;
}
/* 深色背景上的图标变白色 */
.site-header .icon,
.hero .icon,
.site-footer .icon,
.contact .icon,
.top-bar .icon {
  color: #ffffff;
  opacity: 0.92;
}
/* 侧边栏圆形按钮的图标 */
.side-item .icon {
  color: #ffffff;
  opacity: 0.95;
}
/* 优势卡片的大图标 */
.adv-icon .icon {
  font-size: 36px;
  color: var(--blue-700);
  filter: drop-shadow(0 2px 4px rgba(0,87,184,.2));
}
/* 分类标题前缀图标 */
.category-title .icon {
  font-size: 1.15em;
  margin-right: 6px;
}
/* CTA大按钮里的图标 */
.btn .icon {
  margin-right: 4px;
  vertical-align: -1px;
}

/* ========== 顶部联系条 ========== */
.top-bar {
  background: #021024;
  color: rgba(255,255,255,.85);
  font-size: 13px;
  line-height: 36px;
  border-bottom: 1px solid rgba(255,255,255,.06);
}
.top-bar-inner {
  display: flex; justify-content: space-between; align-items: center;
  flex-wrap: wrap; gap: 10px;
}
.top-bar a { color: #fff; }
.top-bar a:hover { color: var(--blue-300); }

/* ========== 头部导航 ========== */
.site-header {
  position: sticky; top: 0; z-index: 500;
  background: linear-gradient(180deg, #021024 0%, #051d3d 100%);
  box-shadow: 0 4px 20px rgba(0,0,0,.4);
  transition: box-shadow .3s;
  border-bottom: 1px solid rgba(0,87,184,.3);
}
.site-header.scrolled { box-shadow: 0 6px 28px rgba(0,0,0,.5); }
.header-inner {
  display: flex; align-items: center; justify-content: space-between;
  height: 88px;
}
.logo img { height: 62px; width: auto; filter: drop-shadow(0 2px 8px rgba(0,87,184,.6)); }
.main-nav ul {
  display: flex; gap: 4px;
  align-items: center; flex-wrap: wrap;
}
.main-nav a {
  display: inline-block; padding: 10px 14px;
  font-size: 15px; color: rgba(255,255,255,.9); font-weight: 500;
  border-radius: 4px;
}
.main-nav a:hover { color: #fff; background: rgba(0,119,230,.25); }
.main-nav .nav-cta {
  background: linear-gradient(135deg, var(--blue-500), var(--blue-400));
  color: #fff; border-radius: 4px; font-weight: 600;
  box-shadow: 0 4px 14px rgba(0,119,230,.5);
}
.main-nav .nav-cta:hover { color: #fff; transform: translateY(-1px); background: linear-gradient(135deg, var(--blue-400), var(--blue-300)); }
.mobile-toggle {
  display: none; font-size: 26px; color: #fff; padding: 8px;
}

/* ========== HERO 轮播 ========== */
.hero {
  position: relative;
  height: 560px; min-height: 480px;
  overflow: hidden;
  background: var(--navy);
}
.hero-slides { position: absolute; inset: 0; }
.hero-slide {
  position: absolute; inset: 0;
  background-size: cover; background-position: center center;
  opacity: 0; transition: opacity .8s ease;
  display: flex; align-items: center;
}
.hero-slide.active { opacity: 1; z-index: 1; }
.hero-slide::before {
  content: ""; position: absolute; inset: 0;
  background: linear-gradient(90deg, rgba(11,37,69,.88) 0%, rgba(11,37,69,.6) 50%, rgba(11,37,69,.2) 100%);
}
.hero-content {
  position: relative; z-index: 2; max-width: 720px;
  color: #fff;
}
.hero-tag {
  display: inline-block;
  background: var(--blue-700); color: #fff;
  padding: 6px 16px; border-radius: 20px;
  font-size: 13px; font-weight: 500; letter-spacing: 2px;
  margin-bottom: 20px;
}
.hero-content h1 {
  font-size: clamp(28px, 5vw, 44px);
  font-weight: 800; margin-bottom: 16px;
  text-shadow: 0 2px 8px rgba(0,0,0,.3);
}
.hero-desc {
  font-size: clamp(15px, 2vw, 18px);
  color: rgba(255,255,255,.9);
  margin-bottom: 32px;
}
.hero-cta { display: flex; gap: 16px; flex-wrap: wrap; }

.hero-arrow {
  position: absolute; top: 50%; transform: translateY(-50%);
  width: 48px; height: 48px; border-radius: 50%;
  background: rgba(255,255,255,.15); color: #fff;
  font-size: 20px; z-index: 10;
  backdrop-filter: blur(6px);
  transition: background .3s;
}
.hero-arrow:hover { background: rgba(0,87,184,.7); }
.hero-prev { left: 24px; }
.hero-next { right: 24px; }

.hero-dots {
  position: absolute; bottom: 28px; left: 50%; transform: translateX(-50%);
  display: flex; gap: 10px; z-index: 10;
}
.hero-dots button {
  width: 36px; height: 4px; border-radius: 2px;
  background: rgba(255,255,255,.4);
  transition: background .3s;
}
.hero-dots button.active { background: #fff; width: 48px; }

/* ========== 按钮 ========== */
.btn {
  display: inline-block; padding: 14px 28px;
  border-radius: 4px; font-weight: 600; font-size: 16px;
  text-align: center; cursor: pointer;
  transition: all .25s ease;
  border: 2px solid transparent;
}
.btn-primary {
  background: linear-gradient(135deg, var(--blue-700), var(--blue-500));
  color: #fff; box-shadow: 0 6px 20px rgba(0,87,184,.35);
}
.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 10px 28px rgba(0,87,184,.5);
  color: #fff;
}
.btn-outline {
  background: transparent; color: #fff;
  border-color: rgba(255,255,255,.7);
}
.btn-outline:hover { background: rgba(255,255,255,.12); color: #fff; }
.btn-big { padding: 18px 36px; font-size: 18px; }

/* ========== 核心优势 ========== */
.advantages {
  background: linear-gradient(180deg, var(--blue-50) 0%, #fff 100%);
  padding: 60px 0;
  border-bottom: 1px solid var(--gray-100);
}
.advantages-grid {
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px;
}
.advantage-card {
  background: #fff;
  padding: 32px 24px; border-radius: 8px;
  text-align: center;
  box-shadow: var(--shadow-sm);
  border-top: 3px solid var(--blue-700);
  transition: transform .3s, box-shadow .3s;
}
.advantage-card:hover {
  transform: translateY(-4px); box-shadow: var(--shadow-md);
}
.adv-icon { font-size: 36px; margin-bottom: 12px; }
.advantage-card h3 { color: var(--navy); margin-bottom: 8px; font-size: 18px; }
.advantage-card p { color: var(--gray-500); font-size: 14px; }

/* ========== Section 通用 ========== */
.section { padding: 80px 0; }
.section-header { text-align: center; margin-bottom: 48px; }
.section-tag {
  color: var(--blue-700); font-size: 13px; letter-spacing: 4px;
  font-weight: 600; margin-bottom: 12px;
}
.section-header h2 {
  font-size: clamp(24px, 3.5vw, 34px); color: var(--navy);
  margin-bottom: 14px; position: relative;
  display: inline-block;
}
.section-header h2::after {
  content: ""; display: block;
  width: 60px; height: 3px;
  background: linear-gradient(90deg, var(--blue-700), var(--blue-400));
  margin: 14px auto 0; border-radius: 2px;
}
.section-sub { color: var(--gray-500); font-size: 15px; max-width: 640px; margin: 0 auto; }

/* ========== 产品中心 ========== */
.products { background: #fff; }
.product-category { margin-bottom: 60px; }
.category-title {
  font-size: 22px; color: var(--navy);
  padding-bottom: 12px; margin-bottom: 14px;
  border-bottom: 2px solid var(--blue-100);
  display: flex; align-items: center; gap: 10px;
}
.category-desc {
  color: var(--gray-700); margin-bottom: 28px;
  font-size: 15px; line-height: 1.8;
}
.product-grid {
  display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px;
}
.product-card {
  background: #fff; border-radius: 8px; overflow: hidden;
  box-shadow: var(--shadow-sm);
  transition: transform .3s, box-shadow .3s;
  border: 1px solid var(--gray-100);
}
.product-card:hover {
  transform: translateY(-4px); box-shadow: var(--shadow-lg);
  border-color: var(--blue-300);
}
.product-card img {
  width: 100%; aspect-ratio: 4/3; object-fit: cover;
  transition: transform .5s;
}
.product-card:hover img { transform: scale(1.04); }
.product-card figcaption { padding: 20px; }
.product-card h4 {
  color: var(--navy); font-size: 18px; margin-bottom: 10px;
}
.product-card p {
  color: var(--gray-500); font-size: 14px; margin-bottom: 12px;
  line-height: 1.7;
}
.product-tags {
  display: flex; flex-wrap: wrap; gap: 6px;
}
.product-tags span {
  background: var(--blue-50); color: var(--blue-700);
  padding: 3px 10px; border-radius: 12px;
  font-size: 12px; font-weight: 500;
}

/* 产品图集 */
.product-gallery { margin-top: 40px; }
.gallery-grid {
  display: grid; grid-template-columns: repeat(6, 1fr); gap: 10px;
}
.gallery-grid a {
  display: block; border-radius: 6px; overflow: hidden;
  aspect-ratio: 4/3;
}
.gallery-grid img {
  width: 100%; height: 100%; object-fit: cover;
  transition: transform .5s;
}
.gallery-grid a:hover img { transform: scale(1.12); }

/* ========== 关于我们 ========== */
.about { background: var(--blue-50); }
.about-inner {
  display: grid; grid-template-columns: 1.3fr 1fr; gap: 48px;
  align-items: center;
}
.about-text h2 { color: var(--navy); font-size: 30px; margin-bottom: 20px; }
.about-text p {
  color: var(--gray-700); margin-bottom: 16px;
  font-size: 15px; line-height: 1.9;
}
.about-text strong { color: var(--blue-700); }
.about-stats {
  display: grid; grid-template-columns: repeat(2, 1fr); gap: 16px;
  margin-top: 28px;
}
.about-stats li {
  background: #fff; padding: 18px; border-radius: 8px;
  border-left: 3px solid var(--blue-700);
}
.about-stats strong {
  display: block; color: var(--blue-700); font-size: 16px; margin-bottom: 4px;
}
.about-stats span { color: var(--gray-500); font-size: 13px; }
.about-image img {
  border-radius: 8px; box-shadow: var(--shadow-lg);
  width: 100%;
}

/* ========== 服务地区 ========== */
.service { background: #fff; }
.cities-grid {
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px;
}
.city-card {
  background: var(--blue-50); border-radius: 8px;
  padding: 20px; border: 1px solid var(--blue-100);
  transition: all .3s;
}
.city-card:hover {
  background: #fff; box-shadow: var(--shadow-md);
  border-color: var(--blue-400); transform: translateY(-2px);
}
.city-card h3 {
  color: var(--navy); font-size: 17px; margin-bottom: 8px;
}
.city-card p { color: var(--gray-500); font-size: 13px; line-height: 1.7; }
.city-card.hot {
  background: linear-gradient(135deg, var(--blue-700), var(--blue-600));
  color: #fff; border-color: transparent;
}
.city-card.hot h3 { color: #fff; }
.city-card.hot p { color: rgba(255,255,255,.85); }
.city-card.warn {
  background: #fff5f5; border-color: #fcc;
}
.city-card.warn h3 { color: #c55; }
.city-card.warn p { color: #a77; }

/* ========== 运输保障 ========== */
.transport { background: var(--gray-100); }
.transport-grid {
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px;
}
.transport-card {
  background: #fff; border-radius: 8px; overflow: hidden;
  box-shadow: var(--shadow-sm);
  transition: transform .3s, box-shadow .3s;
}
.transport-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); }
.transport-card img {
  width: 100%; aspect-ratio: 10/7; object-fit: cover;
}
.transport-card figcaption { padding: 20px; }
.transport-card h3 {
  color: var(--navy); font-size: 17px; margin-bottom: 8px;
}
.transport-card p { color: var(--gray-500); font-size: 14px; line-height: 1.7; }

/* ========== FAQ ========== */
.faq { background: #fff; }
.faq-list { max-width: 900px; margin: 0 auto; }
.faq-list details {
  border-bottom: 1px solid var(--gray-100);
  padding: 18px 0;
}
.faq-list summary {
  cursor: pointer; font-weight: 600;
  color: var(--navy); font-size: 17px;
  list-style: none;
  padding-right: 30px; position: relative;
}
.faq-list summary::-webkit-details-marker { display: none; }
.faq-list summary::after {
  content: "+"; position: absolute; right: 0; top: 50%; transform: translateY(-50%);
  color: var(--blue-700); font-size: 22px; font-weight: 400;
  transition: transform .3s;
}
.faq-list details[open] summary::after { content: "−"; }
.faq-list .q-num {
  color: var(--blue-700); margin-right: 8px; font-weight: 700;
}
.faq-list details p {
  margin-top: 14px; color: var(--gray-700);
  font-size: 15px; line-height: 1.9;
  padding-left: 26px;
}
.faq-list details a { color: var(--blue-700); text-decoration: underline; }
.faq-list details a:hover { color: var(--blue-500); }

/* ========== 联系我们 ========== */
.contact {
  background: linear-gradient(135deg, var(--navy) 0%, var(--blue-800) 100%);
  color: #fff;
}
.contact-inner { max-width: 900px; }
.contact-card {
  background: rgba(255,255,255,.06);
  border: 1px solid rgba(255,255,255,.15);
  border-radius: 12px;
  padding: 48px; text-align: center;
  backdrop-filter: blur(10px);
}
.contact-card h2 { font-size: 28px; margin-bottom: 12px; }
.contact-card > p { color: rgba(255,255,255,.8); margin-bottom: 32px; font-size: 15px; }
.contact-info { text-align: left; max-width: 560px; margin: 0 auto 28px; }
.contact-info p {
  padding: 14px 0; border-bottom: 1px solid rgba(255,255,255,.1);
  font-size: 15px;
}
.contact-info strong { color: var(--blue-300); font-size: 18px; }
.contact-info a:hover { color: var(--blue-300); }
.contact-sub { color: rgba(255,255,255,.6); font-size: 13px; margin-left: 6px; }
.contact-actions { display: flex; gap: 16px; justify-content: center; flex-wrap: wrap; }
.contact .btn-big {
  background: #fff; color: var(--navy);
  border-color: #fff;
}
.contact .btn-big:hover {
  background: var(--blue-300); color: var(--navy);
  transform: translateY(-2px);
}
.contact .btn-outline { border-color: rgba(255,255,255,.5); color: #fff; }
.contact .btn-outline:hover { background: rgba(255,255,255,.1); }

/* ========== 页脚 ========== */
.site-footer {
  background: #061a33; color: rgba(255,255,255,.8);
}
.footer-inner {
  display: grid; grid-template-columns: 1.3fr 1fr 1fr 1fr; gap: 40px;
  padding: 56px 0 32px;
}
.footer-col h4 {
  color: #fff; font-size: 16px; margin-bottom: 18px;
  padding-bottom: 10px; border-bottom: 2px solid var(--blue-700);
  display: inline-block;
}
.footer-col ul li { padding: 6px 0; font-size: 14px; }
.footer-col ul li a { color: rgba(255,255,255,.7); }
.footer-col ul li a:hover { color: var(--blue-300); }
.footer-brand img { height: 64px; width: auto; margin-bottom: 14px; filter: drop-shadow(0 2px 6px rgba(0,119,230,.4)); }
.footer-slogan { font-size: 14px; color: rgba(255,255,255,.6); margin-bottom: 14px; }
.footer-phone { font-size: 15px; }
.footer-phone a { color: var(--blue-300); font-weight: 600; }
.footer-bottom {
  border-top: 1px solid rgba(255,255,255,.08);
  padding: 20px 0; font-size: 13px;
  color: rgba(255,255,255,.5);
  text-align: center;
}
.footer-seo { margin-top: 8px; color: #061a33; font-size: 1px; line-height: 1px; }
.footer-seo a { color: #061a33; }

/* ========== 侧边栏 ========== */
.side-bar {
  position: fixed; right: 16px; bottom: 100px; z-index: 600;
  display: flex; flex-direction: column; gap: 8px;
}
.side-item {
  display: block; width: 52px; height: 52px; border-radius: 50%;
  background: linear-gradient(135deg, var(--blue-700), var(--blue-600));
  color: #fff; text-align: center; line-height: 1.1;
  padding: 8px 0; font-size: 12px; font-weight: 500;
  box-shadow: 0 4px 14px rgba(0,87,184,.4);
  transition: transform .25s;
}
.side-item:hover { transform: scale(1.08); color: #fff; }
.side-icon { font-size: 20px; display: block; margin-bottom: 2px; }

/* ========== 返回顶部 ========== */
.back-top { opacity: 0; pointer-events: none; transition: opacity .3s; }
.back-top.show { opacity: 1; pointer-events: auto; }

/* ========== 响应式 ========== */
@media (max-width: 1100px) {
  .advantages-grid { grid-template-columns: repeat(2, 1fr); }
  .product-grid { grid-template-columns: repeat(2, 1fr); }
  .gallery-grid { grid-template-columns: repeat(4, 1fr); }
  .cities-grid { grid-template-columns: repeat(3, 1fr); }
  .transport-grid { grid-template-columns: repeat(2, 1fr); }
  .about-inner { grid-template-columns: 1fr; }
  .footer-inner { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 860px) {
  .main-nav ul {
    position: absolute; top: 100%; left: 0; right: 0;
    background: #021024; box-shadow: 0 10px 30px rgba(0,0,0,.5);
    flex-direction: column; gap: 0; padding: 10px 0;
    display: none;
    border-top: 1px solid rgba(0,119,230,.3);
  }
  .main-nav.open ul { display: flex; }
  .main-nav li { width: 100%; }
  .main-nav a { display: block; padding: 14px 24px; border-radius: 0; }
  .mobile-toggle { display: block; }

  .hero { height: 480px; min-height: 420px; }
  .hero-arrow { width: 40px; height: 40px; font-size: 16px; }
  .hero-prev { left: 12px; } .hero-next { right: 12px; }

  .section { padding: 60px 0; }
  .advantages { padding: 40px 0; }
  .advantages-grid { grid-template-columns: repeat(2, 1fr); gap: 14px; }
  .advantage-card { padding: 22px 14px; }

  .product-grid { grid-template-columns: 1fr; }
  .gallery-grid { grid-template-columns: repeat(3, 1fr); }
  .cities-grid { grid-template-columns: repeat(2, 1fr); }
  .transport-grid { grid-template-columns: 1fr; }
  .about-stats { grid-template-columns: 1fr 1fr; }
  .contact-card { padding: 32px 20px; }
  .footer-inner { grid-template-columns: 1fr 1fr; gap: 28px; padding: 40px 0 24px; }

  .top-bar { font-size: 12px; line-height: 32px; }
  .hero-cta { gap: 10px; }
  .btn { padding: 12px 20px; font-size: 15px; }
  .btn-big { padding: 14px 24px; font-size: 16px; }
}

@media (max-width: 520px) {
  .advantages-grid { grid-template-columns: 1fr 1fr; }
  .gallery-grid { grid-template-columns: repeat(2, 1fr); }
  .cities-grid { grid-template-columns: 1fr; }
  .footer-inner { grid-template-columns: 1fr; padding-left: 28px; padding-right: 28px; }
  .about-stats { grid-template-columns: 1fr; }
  .hero { height: 420px; }
  .hero-content { padding-top: 20px; }
  .hero-content h1 { font-size: 24px; }
  .hero-arrow { display: none; }
  .side-bar { right: 10px; bottom: 80px; }
  .side-item { width: 46px; height: 46px; font-size: 11px; }
  .side-icon { font-size: 17px; }
}

/* ========== 可访问性 ========== */
@media (prefers-reduced-motion: reduce) {
  * { animation: none !important; transition: none !important; }
  html { scroll-behavior: auto; }
}

:focus { outline: 2px solid var(--blue-400); outline-offset: 2px; }