/* CSS 变量定义 —— 精密五金工业色调（冷蓝拉丝钢 + 加工火花暖铜点缀）
   避开 AI 默认蓝紫系，强调色取自"铜合金 / 加工火花"的行业记忆 */
:root {
  --blue-deep: #0b1b30;
  --blue-anchor: #162d4a;
  --blue-mid: #1e3f63;
  --blue-mid-2: #1e3f63;
  --main-blue: #2563eb;
  --blue-light: #60a5fa;
  --accent-copper: #d4a853;
  --accent-spark: #e8723a;
  --blue-glow: rgba(64, 184, 255, 0.12);

  --section-light: linear-gradient(180deg, var(--blue-mid) 0%, var(--blue-anchor) 55%, var(--blue-deep) 100%);

  --metal-silver: #f1f5f9;  /* 接近白的冷灰 */
  --white: #ffffff;
  --shadow-hard: 0 12px 32px rgba(11, 27, 48, 0.45);
  --radius-sm: 6px;
  --radius-md: 14px;
  --radius-lg: 26px;
  --transition-all: all 0.35s cubic-bezier(0.4, 0, 0.2, 1);
  --glass-bg: rgba(255, 255, 255, 0.12);
  --glass-border: rgba(255, 255, 255, 0.22);
  --mask-dark: rgba(2, 12, 26, 0.72);
  --nav-bg-transparent: rgba(11, 27, 48, 0.40);
  --nav-bg-solid: rgba(11, 27, 48, 0.94);

  /* 字体 token：1.25x 比例体系，覆盖 12px–56px */
  --text-xs: 0.75rem;
  --text-sm: 0.875rem;
  --text-base: 1rem;
  --text-md: 1.0625rem;
  --text-lg: 1.125rem;
  --text-xl: 1.25rem;
  --text-2xl: 1.5rem;
  --text-3xl: 2rem;
  --text-4xl: 2.5rem;
  --text-5xl: 3rem;
  --text-display: 3.5rem;
  --leading-tight: 1.25;
  --leading-body: 1.7;
  --tracking-display: 1px;
}

/* 基础重置 */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  -webkit-tap-highlight-color: transparent;
}

html {
  width: 100%;
  height: 100%;
  overflow-x: hidden;
  scroll-behavior: smooth;
}

body {
  color: var(--metal-silver);
  line-height: 1.75;
  font-size: var(--text-base);
  background-color: transparent;
  font-family: "WenYuan Sans SC Flex VF", "Source Han Sans CN", "PingFang SC", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  user-select: text;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* 动画类 */
.fade-item {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.8s ease-out, transform 0.8s ease-out;
}
.fade-item.active {
  opacity: 1;
  transform: translateY(0);
}

/* 导航栏 */
header {
  background: var(--nav-bg-transparent);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  padding: 20px 5%;
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 9999;
  border-bottom: 1px solid rgba(255,255,255,0.03);
  transition: background 0.4s ease, padding 0.4s ease, box-shadow 0.4s ease;
}

header.scrolled {
  background: var(--nav-bg-solid);
  padding: 14px 5%;
  box-shadow: 0 4px 20px rgba(0,0,0,0.3);
}

.header-wrap {
  max-width: 1480px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo {
  font-size: var(--text-xl);
  font-weight: 700;
  color: #fff;
  letter-spacing: 0.5px;
  cursor: pointer;
  text-decoration: none;
  display: flex;
  align-items: center;
}

.logo span {
  background: linear-gradient(90deg, var(--accent-copper), #e8c97a);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  margin-left: 4px;
}

.lang-toggle {
  margin-left: 24px;
  padding: 8px 16px;
  background: rgba(255,255,255,0.08);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-sm);
  color: #fff;
  font-size: var(--text-sm);
  font-weight: 500;
  cursor: pointer;
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  transition: var(--transition-all);
}
.lang-toggle:hover {
  background: rgba(255,255,255,0.18);
  border-color: var(--accent-copper);
}
.lang-toggle:focus-visible {
  outline: 2px solid var(--blue-light);
  outline-offset: 2px;
}

.nav-pc {
  display: flex;
  align-items: center;
  gap: 32px;
}

.nav-pc a {
  color: rgba(255,255,255,0.85);
  text-decoration: none;
  font-size: var(--text-sm);
  position: relative;
  transition: var(--transition-all);
  padding: 8px 0;
  font-weight: 500;
}

.nav-pc a::after {
  content: "";
  width: 0;
  height: 2px;
  background: var(--accent-copper);
  position: absolute;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%);
  transition: width 0.3s ease;
  border-radius: 1px;
}

.nav-pc a:hover {
  color: #fff;
  text-shadow: 0 0 8px rgba(64, 184, 255, 0.4);
}

.nav-pc a:hover::after {
  width: 100%;
}

/* 汉堡菜单 */
.hamburger {
  display: none;
  width: 32px;
  height: 24px;
  position: relative;
  cursor: pointer;
  z-index: 10001;
  background: transparent;
  border: none;
  padding: 0;
}

.hamburger span {
  display: block;
  width: 100%;
  height: 3px;
  background: var(--accent-copper);
  border-radius: 3px;
  position: absolute;
  transition: var(--transition-all);
}

.hamburger span:nth-child(1) { top: 0; }
.hamburger span:nth-child(2) { top: 10.5px; }
.hamburger span:nth-child(3) { bottom: 0; }

.hamburger.active span:nth-child(1) { transform: rotate(45deg); top: 10.5px; }
.hamburger.active span:nth-child(2) { opacity: 0; }
.hamburger.active span:nth-child(3) { transform: rotate(-45deg); bottom: 10.5px; }

/* 移动端顶部下拉菜单 */
.nav-mobile {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  width: 100%;
  background: rgba(18, 24, 34, 0.98);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  flex-direction: column;
  z-index: 10000;
  transform: translateY(-100%);
  transition: transform 0.4s cubic-bezier(0.4, 0, 0.2, 1);
  padding: 90px 24px 30px;
  box-shadow: 0 12px 30px rgba(0,0,0,0.5);
  max-height: 85vh;
  overflow-y: auto;
}

.nav-mobile.show {
  transform: translateY(0);
}

/* 遮罩层 */
.nav-overlay {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.5);
  z-index: 9999;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.3s ease;
}
.nav-overlay.show {
  opacity: 1;
  pointer-events: auto;
}

.nav-mobile a {
  color: var(--metal-silver);
  text-decoration: none;
  font-size: var(--text-lg);
  padding: 18px 0;
  border-bottom: 1px solid rgba(255,255,255,0.08);
  display: block;
  transition: var(--transition-all);
}

.nav-mobile a:hover {
  color: #fff;
  padding-left: 10px;
}

/* 主容器 */
.main-wrapper {
  width: 100%;
  position: relative;
  background: var(--section-light);
}

#full-wrap {
  width: 100%;
  transition: transform 460ms cubic-bezier(0.22, 0.61, 0.36, 1);
  will-change: transform;
  transform: translate3d(0, 0, 0);
  backface-visibility: hidden;
}

/* Section 通用样式 */
section {
  position: relative;
  width: 100%;
  min-height: 100vh;
  overflow: hidden;
  display: flex;
  align-items: center;
  justify-content: center;
  contain: layout paint;
}

/* 宽屏：整屏切屏动画 */
@media (min-width: 992px) {
  .main-wrapper {
    height: 100vh;
    overflow: hidden;
  }
  #full-wrap {
    height: 100%;
  }
  section {
    height: 100vh;
    min-height: 100vh;
    flex-shrink: 0;
  }
  /* 整屏模式：页脚作为最后一屏。内容超高时由其内部滚动（overflow-y:auto），
     故 isInnerScrollable 需放行任意可滚动祖先，避免后人误改成裁切/隐藏。 */
  #full-wrap > footer {
    height: 100vh;
    min-height: 100vh;
    flex-shrink: 0;
    overflow-y: auto;
    display: flex;
    flex-direction: column;
    justify-content: center;
  }
  /* 整屏模式下区块固定 100vh，内容超高时由内部滚动，避免被裁切/覆盖 */
  .section-inner {
    max-height: 100vh;
    overflow-y: auto;
  }
  /* 整屏 transform 滚动时，固定背景会每帧重绘导致卡顿，关闭之 */
  .section-bg-img {
    background-attachment: scroll;
  }
   /* 滚动动画进行中暂停卡片模糊，避免每帧重新计算 */
   #full-wrap.is-animating .service-card,
   #full-wrap.is-animating .equip-card,
   #full-wrap.is-animating .product-card,
   #full-wrap.is-animating .cert-vertical-item,
   #full-wrap.is-animating .about-img-box img {
     backdrop-filter: none;
     -webkit-backdrop-filter: none;
   }
   /* 视差动画：内容在 3D 空间中比背景平面"浮出" */
   .main-wrapper {
     perspective: 1200px;
   }
   #full-wrap {
     transform-style: preserve-3d;
   }
   #full-wrap > section:not(#footer-contact) .section-inner {
     transform: translateZ(40px);
   }
 }

.section-bg-img {
  background-size: cover;
  background-position: center;
  background-attachment: fixed;
}

@media (max-width: 992px) {
  .section-bg-img {
    background-attachment: scroll;
  }
}

.section-bg-img::before {
  content: "";
  position: absolute;
  inset: 0;
  background: var(--mask-dark);
  z-index: 1;
}

.section-bg-solid {
  background: transparent;
}
.section-bg-solid::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: 1;
  pointer-events: none;
  background:
    radial-gradient(60% 50% at 18% 12%, var(--blue-glow), transparent 70%),
    radial-gradient(55% 45% at 85% 88%, rgba(64, 184, 255, 0.14), transparent 70%);
}

@supports not (backdrop-filter: blur(8px)) {
  .service-card,
  .adv-card,
  .testi-card,
  .faq-item {
    background: rgba(255, 255, 255, 0.35);
  }
}

.section-inner {
  position: relative;
  z-index: 2;
  width: 100%;
  max-width: 1480px;
  padding: 96px 24px 64px;
  display: flex;
  flex-direction: column;
  justify-content: safe center;
}

.section-inner::-webkit-scrollbar {
  width: 6px;
}
.section-inner::-webkit-scrollbar-thumb {
  background: rgba(255,255,255,0.2);
  border-radius: 3px;
}
.section-inner::-webkit-scrollbar-track {
  background: transparent;
}

/* 标题样式 */
.section-title {
  text-align: center;
  margin-bottom: 48px;
}

.section-title h2 {
  font-size: var(--text-4xl);
  color: #ffffff;
  position: relative;
  display: inline-block;
  font-weight: 600;
  letter-spacing: 1px;
  margin-bottom: 24px;
}

.section-title h2::after {
  content: "";
  width: 80px;
  height: 4px;
  background: linear-gradient(90deg, var(--accent-copper), #e8c97a);
  border-radius: 2px;
  position: absolute;
  left: 50%;
  transform: translateX(-50%);
  bottom: -12px;
}

.section-title p {
  margin-top: 30px;
  font-size: var(--text-lg);
  opacity: 0.9;
  max-width: 700px;
  margin-left: auto;
  margin-right: auto;
  color: var(--metal-silver);
}

/* 首屏 Banner —— 用 <img> 替代 CSS background，便于 fetchpriority 提升 LCP */
.banner {
  text-align: center;
}
.banner-hero-img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  z-index: 0;
}

.banner-text {
  position: relative;
  z-index: 2;
  max-width: 900px;
  padding-top: 24px;
  padding-bottom: 24px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  min-height: 360px;
}

.banner-text h1 {
  font-size: var(--text-display);
  margin-bottom: 32px;
  font-weight: 700;
  color: #fff;
  text-shadow: 0 4px 20px rgba(0,0,0,0.5);
  line-height: 1.3;
  letter-spacing: 1px;
}

.banner-text p {
  font-size: var(--text-xl);
  opacity: 0.95;
  max-width: 750px;
  margin-bottom: 40px;
  color: rgba(255,255,255,0.9);
  line-height: 1.6;
}

.banner-btn {
  padding: 16px 40px;
  background: var(--white);
  color: #061a2e;
  border: none;
  border-radius: var(--radius-lg);
  font-size: var(--text-lg);
  cursor: pointer;
  font-weight: 700;
  box-shadow: 0 8px 28px rgba(212, 168, 83, 0.35);
  transition: var(--transition-all);
  display: inline-block;
}

.banner-btn:hover {
  transform: translateY(-4px);
  background: #f5f0e8;
  box-shadow: 0 12px 34px rgba(212, 168, 83, 0.5);
}

/* Hero 数据论点条 */
.hero-stats {
  display: flex;
  gap: 48px;
  margin: 36px 0 32px;
}
.hero-stat {
  text-align: center;
}
.hero-stat-num {
  display: block;
  font-size: var(--text-3xl);
  font-weight: 700;
  letter-spacing: 1px;
  color: var(--accent-copper);
  line-height: 1.2;
}
.hero-stat-label {
  display: block;
  font-size: var(--text-xs);
  opacity: 0.8;
  color: rgba(255,255,255,0.75);
  margin-top: 4px;
  letter-spacing: 1px;
}

@media (max-width: 768px) {
  .hero-stats {
    gap: 24px;
    margin: 24px 0 20px;
  }
  .hero-stat-num {
    font-size: var(--text-xl);
  }
}

/* 关于我们 */
.about-wrap {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 56px;
  align-items: center;
}
.about-text p {
  margin-bottom: 22px;
  font-size: var(--text-xl);
  opacity: 0.92;
  line-height: 2;
}
.about-img-box {
  display: block;
  width: 100%;
}
.about-img-box img {
  display: block;
  width: 100%;
  max-width: 80%;
  margin: 0 auto;
  height: auto;
  max-height: 70vh;
  object-fit: cover;
  border-radius: var(--radius-md);
  border: 1px solid var(--glass-border);
  transition: var(--transition-all);
}
.about-img-box img:hover {
  transform: scale(1.04);
  box-shadow: var(--shadow-hard);
}

/* 业务卡片 */
.service-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  contain: layout style;
}
.service-card {
  padding: 32px 22px;
  background: var(--glass-bg);
  backdrop-filter: blur(8px);
  border-radius: var(--radius-md);
  border: 1px solid var(--glass-border);
  transition: var(--transition-all);
  text-align: center;
}
.service-card:hover {
  transform: translateY(-8px);
  background: rgba(255,255,255,0.15);
  box-shadow: var(--shadow-hard);
}
.service-icon {
  color: var(--accent-copper);
  margin-bottom: 20px;
  display: inline-block;
}
.service-icon,
.adv-icon {
  background-repeat: no-repeat;
  background-position: center;
  background-size: contain;
}
.service-icon.icon-s1 {
  width: 44px; height: 44px;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='44' height='44' viewBox='0 0 24 24' fill='none' stroke='%23d4a853' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='M15.707 21.293a1 1 0 0 1-1.414 0l-1.586-1.586a1 1 0 0 1 0-1.414l5.586-5.586a1 1 0 0 1 1.414 0l1.586 1.586a1 1 0 0 1 0 1.414z'/%3E%3Cpath d='m18 13-1.375-6.874a1 1 0 0 0-.746-.776L3.235 2.028a1 1 0 0 0-1.207 1.207L5.35 15.879a1 1 0 0 0 .776.746L13 18'/%3E%3Cpath d='m2.3 2.3 7.286 7.286'/%3E%3Ccircle cx='11' cy='11' r='2'/%3E%3C/svg%3E");
}
.service-icon.icon-s2 {
  width: 44px; height: 44px;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='44' height='44' viewBox='0 0 24 24' fill='none' stroke='%23d4a853' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpolyline points='16 18 22 12 16 6'/%3E%3Cpolyline points='8 6 2 12 8 18'/%3E%3C/svg%3E");
}
.service-icon.icon-s3 {
  width: 44px; height: 44px;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='44' height='44' viewBox='0 0 24 24' fill='none' stroke='%23d4a853' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='M16 21v-2a4 4 0 0 0-4-4H6a4 4 0 0 0-4 4v2'/%3E%3Ccircle cx='9' cy='7' r='4'/%3E%3Cpath d='M22 21v-2a4 4 0 0 0-3-3.87'/%3E%3Cpath d='M16 3.13a4 4 0 0 1 0 7.75'/%3E%3C/svg%3E");
}
.service-icon.icon-s4 {
  width: 44px; height: 44px;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='44' height='44' viewBox='0 0 24 24' fill='none' stroke='%23d4a853' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='M3 3v16a2 2 0 0 0 2 2h16'/%3E%3Cpath d='M7 16h8'/%3E%3Cpath d='M7 11h12'/%3E%3Cpath d='M7 6h3'/%3E%3C/svg%3E");
}
.adv-icon {
  color: var(--accent-copper);
  margin-bottom: 16px;
  display: inline-block;
}
.adv-icon.icon-a1 {
  width: 36px; height: 36px;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='36' height='36' viewBox='0 0 24 24' fill='none' stroke='%23d4a853' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Ccircle cx='12' cy='12' r='10'/%3E%3Cline x1='12' y1='8' x2='12' y2='12'/%3E%3Cline x1='12' y1='16' x2='12.01' y2='16'/%3E%3C/svg%3E");
}
.adv-icon.icon-a2 {
  width: 36px; height: 36px;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='36' height='36' viewBox='0 0 24 24' fill='none' stroke='%23d4a853' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpolyline points='9 11 12 14 22 4'/%3E%3Cpath d='M21 12v7a2 2 0 0 1-2 2H5a2 2 0 0 1-2-2V5a2 2 0 0 1 2-2h11'/%3E%3C/svg%3E");
}
.adv-icon.icon-a3 {
  width: 36px; height: 36px;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='36' height='36' viewBox='0 0 24 24' fill='none' stroke='%23d4a853' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Ccircle cx='12' cy='12' r='10'/%3E%3Cpolyline points='12 6 12 12 16 14'/%3E%3C/svg%3E");
}
.adv-icon.icon-a4 {
  width: 36px; height: 36px;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='36' height='36' viewBox='0 0 24 24' fill='none' stroke='%23d4a853' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='M21 16V8a2 2 0 0 0-1-1.73l-7-4a2 2 0 0 0-2 0l-7 4A2 2 0 0 0 3 8v8a2 2 0 0 0 1 1.73l7 4a2 2 0 0 0 2 0l7-4A2 2 0 0 0 21 16z'/%3E%3Cpolyline points='3.27 6.96 12 12.01 20.73 6.96'/%3E%3Cline x1='12' y1='22.08' x2='12' y2='12'/%3E%3C/svg%3E");
}
.service-card h3 {
  font-size: var(--text-lg);
  font-weight: 600;
  margin-bottom: 14px;
  color: #fff;
}
.service-card p {
  opacity: 0.85;
  font-size: var(--text-sm);
  line-height: 1.7;
}
/* 权威资质 - 三证同尺寸、顶部/底部对齐 */
.cert-vertical {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  justify-content: center;
  align-items: stretch;
  contain: layout style;
}
.cert-vertical-item {
  background: rgba(255,255,255,0.45);
  border: 1px solid rgba(255,255,255,0.6);
  backdrop-filter: blur(4px);
  border-radius: var(--radius-md);
  overflow: hidden;
  transition: var(--transition-all);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  height: 460px;            /* 三卡等高，证书统一尺寸 */
  min-width: 0;
}
.cert-vertical-item:hover {
  transform: translateY(-8px);
  background: rgba(255,255,255,0.6);
  box-shadow: var(--shadow-hard);
}
.cert-vertical-item img {
  display: block;
  width: auto;
  height: 100%;
  max-width: 100%;
  object-fit: contain;
  background: transparent;
}

/* 设备与产品 */
.equip-grid, .product-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 24px;
  contain: layout style;
}
/* 产品展示：固定四栏 → 两栏 → 单栏 响应式 */
.product-grid {
  grid-template-columns: repeat(4, 1fr);
}
.equip-card, .product-card {
  background: var(--glass-bg);
  backdrop-filter: blur(8px);
  border-radius: var(--radius-md);
  overflow: hidden;
  border: 1px solid var(--glass-border);
  transition: var(--transition-all);
  position: relative;
  cursor: pointer;
  min-width: 0;
}
.equip-card:hover, .product-card:hover {
  transform: translateY(-8px);
  background: rgba(255,255,255,0.18);
  box-shadow: var(--shadow-hard);
}
.equip-card img, .product-card img {
  width: 100%;
  height: 220px;
  object-fit: cover;
  transition: var(--transition-all);
}
.equip-card:hover img, .product-card:hover img {
  transform: scale(1.08);
}

.product-card {
  height: 300px;
  padding: 0;
  background: transparent;
  border: none;
  backdrop-filter: none;
  position: relative;
  overflow: hidden;
}
.product-card::after {
  content: var(--cta-text, "查看详情");
  position: absolute;
  right: 12px;
  bottom: 12px;
  padding: 6px 14px;
  background: rgba(11, 27, 48, 0.72);
  color: var(--accent-copper);
  font-size: var(--text-sm);
  border-radius: var(--radius-sm);
  border: 1px solid rgba(212,168,83,0.35);
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
  opacity: 0;
  transform: translateY(6px);
  transition: opacity 0.3s ease, transform 0.3s ease;
  pointer-events: none;
  white-space: nowrap;
  letter-spacing: 0.5px;
  z-index: 2;
}
.product-card:hover::after {
  opacity: 1;
  transform: translateY(0);
}
@media (max-width: 768px) {
  .product-card::after {
    opacity: 1;
    transform: none;
    padding: 6px 10px;
    font-size: var(--text-xs);
    right: 8px;
    bottom: 8px;
    background: rgba(11, 27, 48, 0.82);
    border-color: rgba(212,168,83,0.5);
  }
}
.product-card > img {
  height: 100%;
  object-fit: cover;
}

.equip-text {
  position: absolute;
  bottom: 0;
  left: 0;
  width: 100%;
  padding: 16px 14px;
  background: linear-gradient(to top, rgba(0,0,0,0.85), transparent);
  color: #fff;
}
.product-text {
  position: absolute;
  bottom: 0;
  left: 0;
  width: 100%;
  padding: 16px 14px;
  color: var(--accent-copper);
}
.product-card .product-text {
  display: none;
}
.product-text h3 {
  font-size: var(--text-lg);
  margin-bottom: 6px;
  font-weight: 600;
  color: var(--accent-copper);
}
.product-text p {
  display: none;
}
.product-long-desc {
  display: none;
}

@supports not (backdrop-filter: blur(8px)) {
  .service-card,
  .adv-card,
  .testi-card,
  .faq-item {
    background: rgba(255, 255, 255, 0.35);
  }
}

/* 主营业务：合作客户品牌 logo 展位（语义化列表） */
.partner-strip {
  margin-top: 56px;
  text-align: center;
}
.partner-logos {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 18px;
  list-style: none;
}
.partner-logo {
  width: 180px;
  height: 96px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(255,255,255,0.92);
  border-radius: var(--radius-sm);
  padding: 14px 18px;
  transition: var(--transition-all);
}
.partner-logo:hover {
  transform: translateY(-4px);
  background: #ffffff;
  box-shadow: var(--shadow-hard);
}
.partner-logo img {
  max-width: 100%;
  max-height: 64px;
  object-fit: contain;
}

/* 图片弹窗
   两种模式：
   - simple-mode：设备/资质/关于等图片，只显示居中大图
   - product-mode：产品卡片，左图右文 + 左右切换 */
.img-modal {
  position: fixed;
  z-index: 100001;
  inset: 0;
  background: linear-gradient(135deg, rgba(11,27,48,0.97), rgba(22,45,74,0.97));
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 30px;
  visibility: hidden;
  opacity: 0;
  transition: opacity 0.3s ease, visibility 0.3s ease;
}
.img-modal.show {
  visibility: visible;
  opacity: 1;
}
.img-modal.simple-mode .modal-body {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 100%;
  max-width: 1400px;
}
.img-modal.simple-mode .modal-text {
  display: none;
}
.img-modal.simple-mode .preview-img {
  max-width: 92vw;
  max-height: 88vh;
}

.img-modal.product-mode .modal-body {
  display: flex;
  gap: 24px;
  width: 90vw;
  max-width: 1200px;
  align-items: stretch;
}
.img-modal.product-mode .preview-img {
  flex: 1;
  max-height: 80vh;
  object-fit: contain;
  border-radius: var(--radius-sm);
  box-shadow: 0 20px 50px rgba(0,0,0,0.5);
}
.img-modal.product-mode .modal-text {
  display: block;
  flex: 0 0 320px;
  color: #fff;
  overflow-y: auto;
  max-height: 80vh;
  padding: 32px 20px;
}

.close-btn {
  position: absolute;
  top: 40px;
  right: 40px;
  color: #fff;
  font-size: var(--text-4xl);
  cursor: pointer;
  user-select: none;
  transition: var(--transition-all);
  opacity: 0.8;
  z-index: 100002;
  background: none;
  border: none;
  line-height: 1;
}
.close-btn:hover {
  color: var(--blue-light);
  transform: scale(1.1);
  opacity: 1;
}
.modal-text {
  display: none;
}
.modal-product-name {
  font-size: var(--text-2xl);
  font-weight: 600;
  margin-bottom: 16px;
  color: var(--accent-copper);
}
.modal-product-desc {
  line-height: 2;
  white-space: pre-line;
  opacity: 0.9;
  font-size: var(--text-sm);
}
.modal-prev, .modal-next {
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  background: rgba(255,255,255,0.12);
  border: 1px solid rgba(255,255,255,0.25);
  color: #fff;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  cursor: pointer;
  font-size: var(--text-xl);
  display: none;
  align-items: center;
  justify-content: center;
  backdrop-filter: blur(6px);
  transition: var(--transition-all);
  z-index: 100003;
}
.img-modal.product-mode .modal-prev,
.img-modal.product-mode .modal-next {
  display: flex;
}
.modal-prev:hover, .modal-next:hover {
  background: var(--accent-copper);
  border-color: var(--accent-copper);
  color: #fff;
}
.modal-prev {
  left: 20px;
}
.modal-next {
  right: 20px;
}

@media (max-width: 768px) {
  .img-modal.product-mode .modal-body {
    flex-direction: column;
  }
  .img-modal.product-mode .modal-text {
    flex: none;
    max-height: none;
  }
  .modal-prev, .modal-next {
    width: 40px;
    height: 40px;
    font-size: var(--text-lg);
  }
  .modal-prev { left: 10px; }
  .modal-next { right: 10px; }
}

/* 页脚优化 */
footer {
  position: relative;
  background: transparent;
  color: #f1f5f9;
  padding: 64px 5% 48px;
  display: flex;
  flex-direction: column;
  align-items: center;
  border-top: 1px solid rgba(255,255,255,0.08);
}

.footer-content {
  width: 100%;
  max-width: 1480px;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 36px;
  margin-bottom: 36px;
}

.footer-col h4 {
  color: #ffffff;
  font-size: var(--text-xl);
  margin-bottom: 24px;
  position: relative;
  padding-bottom: 12px;
  font-weight: 600;
}

.footer-col h4::after {
  content: "";
  width: 40px;
  height: 3px;
  background: var(--accent-copper);
  position: absolute;
  left: 0;
  bottom: 0;
  border-radius: 2px;
}

.footer-col p {
  margin: 14px 0;
  font-size: var(--text-sm);
  opacity: 0.85;
  line-height: 1.7;
  color: rgba(241,245,249,0.85);
}

.footer-col a {
  color: #ffffff;
  text-decoration: underline;
}
.footer-link {
  color: #ffffff;
  text-decoration: underline;
}

.copyright {
  text-align: center;
  padding-top: 40px;
  border-top: 1px solid rgba(255,255,255,0.08);
  font-size: var(--text-sm);
  opacity: 0.65;
  width: 100%;
  color: rgba(241,245,249,0.65);
}

/* 右侧圆点导航 */
.page-nav {
  position: fixed;
  right: 30px;
  top: 50%;
  transform: translateY(-50%);
  z-index: 100;
  display: flex;
  flex-direction: column;
  gap: 16px;
}
.page-nav-dot {
  width: 12px;
  height: 12px;
  border-radius: 50%;
  border: 1px solid rgba(15, 23, 42, 0.25);
  background: rgba(255,255,255,0.9);
  cursor: pointer;
  transition: var(--transition-all);
}
.page-nav-dot.active {
  background: var(--accent-copper);
  transform: scale(1.3);
  border-color: var(--accent-copper);
}

/* 核心优势 */
.adv-subtitle {
  text-align: center;
  font-size: var(--text-lg);
  color: var(--accent-copper);
  font-weight: 600;
  margin-top: 56px;
  margin-bottom: 32px;
}
.adv-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  contain: layout style;
}
.adv-card {
  padding: 28px 20px;
  background: var(--glass-bg);
  backdrop-filter: blur(8px);
  border-radius: var(--radius-md);
  border: 1px solid var(--glass-border);
  text-align: center;
  transition: var(--transition-all);
}
.adv-card:hover {
  transform: translateY(-6px);
  background: rgba(255,255,255,0.15);
  box-shadow: var(--shadow-hard);
}
.adv-icon {
  color: var(--accent-copper);
  margin-bottom: 16px;
  display: inline-block;
}
.adv-card h4 {
  font-size: var(--text-lg);
  font-weight: 600;
  margin-bottom: 10px;
  color: #fff;
}
.adv-card p {
  font-size: var(--text-sm);
  opacity: 0.85;
  line-height: 1.6;
}

/* 客户评价 - 内嵌于合作伙伴模块 */
.testimonials-inline {
  margin-top: 56px;
}
.testi-subtitle {
  text-align: center;
  font-size: var(--text-xl);
  color: var(--accent-copper);
  font-weight: 600;
  margin-bottom: 28px;
}
.testi-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  contain: layout style;
}
.testi-card {
  padding: 24px;
  background: var(--glass-bg);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-md);
  backdrop-filter: blur(6px);
  transition: var(--transition-all);
}
.testi-card:hover {
  transform: translateY(-4px);
  background: rgba(255,255,255,0.12);
  box-shadow: var(--shadow-hard);
}
.testi-card p {
  font-size: var(--text-sm);
  opacity: 0.92;
  line-height: 1.75;
  margin-bottom: 14px;
  color: #fff;
}
.testi-card span {
  font-size: var(--text-xs);
  opacity: 0.7;
  color: var(--accent-copper);
}

/* 常见问题 - 手风琴折叠面板 */
.faq-list {
  max-width: 820px;
  margin: 0 auto;
}
.faq-item {
  margin-bottom: 12px;
  background: var(--glass-bg);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-md);
  backdrop-filter: blur(6px);
  overflow: hidden;
  transition: var(--transition-all);
}
.faq-header {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 22px 28px;
  background: none;
  border: none;
  color: #fff;
  cursor: pointer;
  text-align: left;
  font-family: inherit;
  font-size: inherit;
  transition: var(--transition-all);
}
.faq-header:hover .faq-question {
  color: var(--accent-copper);
}
.faq-question {
  font-size: var(--text-md);
  font-weight: 600;
  color: #fff;
  transition: color 0.25s ease;
  flex: 1;
}
.faq-arrow {
  width: 20px;
  height: 20px;
  position: relative;
  flex-shrink: 0;
  transition: transform 0.3s ease;
}
.faq-arrow::before {
  content: "";
  position: absolute;
  left: 50%;
  top: 50%;
  width: 10px;
  height: 10px;
  border-right: 2px solid #fff;
  border-bottom: 2px solid #fff;
  transform: translate(-50%, -50%) rotate(45deg);
}
.faq-item.open .faq-arrow {
  transform: rotate(180deg);
}
.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.35s ease, opacity 0.35s ease;
  opacity: 0;
}
.faq-item.open .faq-answer {
  max-height: 300px;
  opacity: 1;
}
.faq-answer p {
  padding: 0 28px 22px;
  font-size: var(--text-sm);
  opacity: 0.88;
  line-height: 1.75;
  color: var(--metal-silver);
}

@media (max-width:1200px) {
  .service-grid { grid-template-columns: repeat(2, 1fr); }
  .about-wrap { grid-template-columns: 1fr; gap: 40px; }
  .cert-vertical { grid-template-columns: repeat(2, 1fr); }
  .adv-grid { grid-template-columns: repeat(2, 1fr); }
  .testi-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width:768px) {
  .adv-grid { grid-template-columns: 1fr; }
  .testi-grid { grid-template-columns: 1fr; }
  .faq-header { padding: 18px 20px; }
  .faq-answer p { padding: 0 20px 18px; }
  .partner-logo { width: 140px; height: 76px; }
  .service-grid { grid-template-columns: 1fr; }
  .cert-vertical { grid-template-columns: repeat(2, 1fr); gap: 20px; max-width: 560px; margin: 0 auto; }
  .equip-grid { grid-template-columns: repeat(2, 1fr); gap: 18px; }
  .product-grid { grid-template-columns: repeat(2, 1fr); gap: 18px; }
  .footer-content { grid-template-columns: 1fr; gap: 28px; }
  .banner-text h1 { font-size: var(--text-3xl); line-height: 1.25; }
  .banner-text p { font-size: var(--text-base); }
  .banner-btn { font-size: var(--text-base); padding: 14px 32px; }
  .section-title { margin-bottom: 32px; }
  .section-title h2 { font-size: var(--text-2xl); }
  .section-title p { font-size: var(--text-sm); margin-top: 22px; }
  .section-inner { padding: 84px 18px 40px; }
  .about-text h3 { font-size: var(--text-xl); }
  .about-img-box img { max-height: 52vh; }
  .partner-strip { margin-top: 44px; }
}

@media (max-width:992px) {
  .nav-pc { display: none; }
  .hamburger { display: block; }
  .nav-mobile { display: flex; }
  .nav-overlay { display: block; }

  .banner-text h1 { font-size: var(--text-4xl); }
  .section-title h2 { font-size: var(--text-3xl); }
  .page-nav { display: none; }

  .section-inner { padding-top: 88px; padding-bottom: 52px; }
}

.nav-pc a:focus-visible,
.nav-mobile a:focus-visible,
.hamburger:focus-visible,
.banner-btn:focus-visible,
.close-btn:focus-visible,
.equip-card:focus-visible,
.product-card:focus-visible,
.cert-vertical-item:focus-visible,
.about-img-box:focus-visible {
  outline: 2px solid var(--blue-light);
  outline-offset: 4px;
  border-radius: 4px;
}

/* 手机：单列呈现，限制图片高度避免过长 */
@media (max-width:480px) {
  .cert-vertical { grid-template-columns: 1fr; gap: 18px; max-width: 360px; }
  .equip-grid { grid-template-columns: 1fr; }
  .product-grid { grid-template-columns: 1fr; }
  .equip-card img { height: 200px; }
  .about-img-box img { max-height: 46vh; }
  .service-card { padding: 26px 18px; }
}

/* 无障碍：尊重系统的减少动画偏好 */
@media (prefers-reduced-motion: reduce) {
  * {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
    scroll-behavior: auto !important;
  }
  .fade-item { opacity: 1; transform: none; }
}

/* 仅读屏可见的隐藏文本（如弹窗标题） */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
  border: 0;
}

/* Skip-to-Content */
.skip-link {
  position: absolute;
  top: -48px;
  left: 0;
  background: var(--accent-copper);
  color: var(--blue-deep);
  padding: 8px 16px;
  z-index: 100000;
  font-weight: 600;
  transition: top 0.2s;
}
.skip-link:focus { top: 0; }