/* 企讯科技官网 - 主样式文件 */

/* ===== 重置与基础 ===== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --primary: #1a6fc4;
  --primary-dark: #1558a0;
  --primary-light: #3b8fe8;
  --accent: #00b4d8;
  --text-dark: #1a1a2e;
  --text-body: #444;
  --text-muted: #888;
  --bg-light: #f5f7fa;
  --bg-white: #fff;
  --border: #e5e8ef;
  --shadow: 0 4px 24px rgba(26,111,196,0.08);
  --shadow-lg: 0 8px 40px rgba(26,111,196,0.14);
  --radius: 10px;
  --radius-lg: 18px;
  --transition: 0.28s cubic-bezier(.4,0,.2,1);
  --header-h: 72px;
}

html { scroll-behavior: smooth; }
body { font-family: 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', Arial, sans-serif; color: var(--text-body); background: var(--bg-white); line-height: 1.7; font-size: 15px; }
img { max-width: 100%; display: block; }
a { color: var(--primary); text-decoration: none; transition: color var(--transition); }
a:hover { color: var(--primary-light); }
ul { list-style: none; }

.container { max-width: 1200px; margin: 0 auto; padding: 0 24px; }
.section { padding: 80px 0; }
.section-alt { background: var(--bg-light); }

/* ===== 头部导航 ===== */
.header {
  position: fixed; top: 0; left: 0; right: 0; z-index: 1000;
  height: var(--header-h);
  background: rgba(255,255,255,0.97);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
  box-shadow: 0 2px 16px rgba(0,0,0,0.05);
  transition: box-shadow var(--transition);
}
.header.scrolled { box-shadow: var(--shadow-lg); }

.header-inner {
  display: flex; align-items: center; justify-content: space-between;
  height: var(--header-h);
}

.logo { display: flex; align-items: center; gap: 12px; }
.logo img { height: 42px; width: auto; }
.logo-text { display: flex; flex-direction: column; line-height: 1.2; }
.logo-name { font-size: 17px; font-weight: 700; color: var(--primary); letter-spacing: 1px; }
.logo-slogan { font-size: 11px; color: var(--text-muted); letter-spacing: 0.5px; }

.nav { display: flex; align-items: center; gap: 4px; }
.nav-link {
  padding: 8px 18px; border-radius: 6px;
  font-size: 15px; font-weight: 500; color: var(--text-dark);
  transition: all var(--transition);
  position: relative;
}
.nav-link::after {
  content: ''; position: absolute; bottom: 4px; left: 50%; right: 50%;
  height: 2px; background: var(--primary); border-radius: 2px;
  transition: all var(--transition);
}
.nav-link:hover, .nav-link.active { color: var(--primary); background: rgba(26,111,196,0.06); }
.nav-link:hover::after, .nav-link.active::after { left: 18px; right: 18px; }

.header-cta {
  display: flex; align-items: center; gap: 12px;
}
.btn-header-phone { 
  display: flex; align-items: center; gap: 6px;
  color: var(--primary); font-weight: 600; font-size: 14px;
}
.btn-header-phone i { color: var(--accent); }
.btn-contact {
  padding: 9px 22px; background: var(--primary); color: #fff !important;
  border-radius: 6px; font-size: 14px; font-weight: 600;
  transition: all var(--transition);
  box-shadow: 0 2px 10px rgba(26,111,196,0.25);
}
.btn-contact:hover { background: var(--primary-dark); box-shadow: 0 4px 16px rgba(26,111,196,0.35); transform: translateY(-1px); }

/* 移动菜单 */
.menu-toggle { display: none; flex-direction: column; gap: 5px; cursor: pointer; padding: 6px; }
.menu-toggle span { display: block; width: 24px; height: 2px; background: var(--text-dark); border-radius: 2px; transition: all var(--transition); }

/* ===== Hero 首页Banner ===== */
.hero {
  padding-top: var(--header-h);
  min-height: 100vh;
  display: flex; flex-direction: column;
  position: relative;
  overflow: hidden;
}

.hero-slider { position: relative; flex: 1; display: flex; flex-direction: column; }
.hero-slide {
  display: none; flex: 1;
  align-items: center;
  min-height: calc(100vh - var(--header-h));
  padding: 60px 0 40px;
  background: linear-gradient(135deg, #0a2744 0%, #1a4f8a 40%, #1a6fc4 70%, #3b8fe8 100%);
  position: relative;
}
.hero-slide.active { display: flex; animation: fadeIn 0.6s ease; }
.hero-slide::before {
  content: '';
  position: absolute; inset: 0;
  background: url("data:image/svg+xml,%3Csvg width='60' height='60' viewBox='0 0 60 60' xmlns='http://www.w3.org/2000/svg'%3E%3Cg fill='none' fill-rule='evenodd'%3E%3Cg fill='%23ffffff' fill-opacity='0.03'%3E%3Cpath d='M36 34v-4h-2v4h-4v2h4v4h2v-4h4v-2h-4zm0-30V0h-2v4h-4v2h4v4h2V6h4V4h-4zM6 34v-4H4v4H0v2h4v4h2v-4h4v-2H6zM6 4V0H4v4H0v2h4v4h2V6h4V4H6z'/%3E%3C/g%3E%3C/g%3E%3C/svg%3E");
}

.hero-content { position: relative; z-index: 2; color: #fff; }
.hero-badge {
  display: inline-block; padding: 5px 14px;
  background: rgba(255,255,255,0.15); border: 1px solid rgba(255,255,255,0.25);
  border-radius: 20px; font-size: 12px; letter-spacing: 2px;
  margin-bottom: 24px; backdrop-filter: blur(4px);
}
.hero-title {
  font-size: clamp(32px, 5vw, 58px); font-weight: 800;
  line-height: 1.2; margin-bottom: 20px;
  letter-spacing: -0.5px;
}
.hero-title em { font-style: normal; color: #7dd3fc; }
.hero-subtitle { font-size: 18px; opacity: 0.85; margin-bottom: 40px; max-width: 520px; line-height: 1.6; }
.hero-actions { display: flex; gap: 16px; flex-wrap: wrap; }

.btn-primary {
  padding: 14px 32px; background: #fff; color: var(--primary) !important;
  border-radius: 8px; font-size: 16px; font-weight: 700;
  box-shadow: 0 4px 20px rgba(0,0,0,0.15);
  transition: all var(--transition); display: inline-flex; align-items: center; gap: 8px;
}
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 8px 30px rgba(0,0,0,0.2); }
.btn-outline-white {
  padding: 14px 32px; border: 2px solid rgba(255,255,255,0.5); color: #fff !important;
  border-radius: 8px; font-size: 16px; font-weight: 600;
  transition: all var(--transition); display: inline-flex; align-items: center; gap: 8px;
}
.btn-outline-white:hover { background: rgba(255,255,255,0.12); border-color: rgba(255,255,255,0.8); }

.hero-visual {
  position: relative; z-index: 2;
  display: flex; justify-content: center; align-items: center;
}
.hero-card {
  background: rgba(255,255,255,0.1); backdrop-filter: blur(20px);
  border: 1px solid rgba(255,255,255,0.2); border-radius: var(--radius-lg);
  padding: 32px; color: #fff; max-width: 380px; width: 100%;
}
.hero-card-title { font-size: 18px; font-weight: 700; margin-bottom: 20px; display: flex; align-items: center; gap: 10px; }
.hero-stats { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.stat-item { text-align: center; padding: 16px; background: rgba(255,255,255,0.1); border-radius: 10px; }
.stat-number { font-size: 28px; font-weight: 800; color: #7dd3fc; line-height: 1; }
.stat-label { font-size: 12px; opacity: 0.8; margin-top: 4px; }

/* 轮播控制 */
.slider-controls {
  position: absolute; bottom: 32px; left: 50%; transform: translateX(-50%);
  display: flex; gap: 8px; z-index: 10;
}
.slider-dot {
  width: 8px; height: 8px; border-radius: 4px; background: rgba(255,255,255,0.4);
  cursor: pointer; transition: all var(--transition);
}
.slider-dot.active { width: 28px; background: #fff; }
.slider-prev, .slider-next {
  position: absolute; top: 50%; transform: translateY(-50%);
  width: 44px; height: 44px; border-radius: 50%;
  background: rgba(255,255,255,0.15); border: none; cursor: pointer;
  display: flex; align-items: center; justify-content: center;
  color: #fff; font-size: 16px; z-index: 10;
  transition: all var(--transition); backdrop-filter: blur(4px);
}
.slider-prev { left: 24px; }
.slider-next { right: 24px; }
.slider-prev:hover, .slider-next:hover { background: rgba(255,255,255,0.25); }

/* ===== 数字统计 ===== */
.stats-bar {
  background: var(--primary);
  padding: 0;
}
.stats-grid {
  display: grid; grid-template-columns: repeat(4, 1fr);
}
.stat-block {
  padding: 32px 20px; text-align: center;
  border-right: 1px solid rgba(255,255,255,0.15);
  transition: background var(--transition);
}
.stat-block:last-child { border-right: none; }
.stat-block:hover { background: rgba(255,255,255,0.06); }
.stat-block-number {
  font-size: 42px; font-weight: 800; color: #fff; line-height: 1;
  display: flex; align-items: baseline; justify-content: center; gap: 2px;
}
.stat-block-number em { font-style: normal; font-size: 20px; font-weight: 600; opacity: 0.85; }
.stat-block-label { font-size: 13px; color: rgba(255,255,255,0.72); margin-top: 8px; }

/* ===== Section 标题 ===== */
.section-header { text-align: center; margin-bottom: 56px; }
.section-tag {
  display: inline-block; padding: 4px 14px;
  background: rgba(26,111,196,0.1); color: var(--primary);
  border-radius: 20px; font-size: 12px; font-weight: 600; letter-spacing: 1px;
  margin-bottom: 12px;
}
.section-title {
  font-size: clamp(26px, 3.5vw, 40px); font-weight: 800;
  color: var(--text-dark); margin-bottom: 14px; letter-spacing: -0.3px;
}
.section-desc { font-size: 16px; color: var(--text-muted); max-width: 520px; margin: 0 auto; }
.section-line {
  width: 48px; height: 3px; background: linear-gradient(90deg, var(--primary), var(--accent));
  border-radius: 3px; margin: 16px auto 0;
}

/* ===== 产品服务 ===== */
.products-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 28px; }
.product-card {
  background: var(--bg-white); border-radius: var(--radius-lg);
  padding: 36px 28px; border: 1px solid var(--border);
  transition: all var(--transition); position: relative; overflow: hidden;
}
.product-card::before {
  content: ''; position: absolute; top: 0; left: 0; right: 0;
  height: 3px; background: linear-gradient(90deg, var(--primary), var(--accent));
  opacity: 0; transition: opacity var(--transition);
}
.product-card:hover { transform: translateY(-6px); box-shadow: var(--shadow-lg); border-color: transparent; }
.product-card:hover::before { opacity: 1; }

.product-icon {
  width: 60px; height: 60px; border-radius: 14px;
  background: linear-gradient(135deg, rgba(26,111,196,0.12), rgba(0,180,216,0.12));
  display: flex; align-items: center; justify-content: center;
  font-size: 26px; color: var(--primary); margin-bottom: 20px;
  transition: all var(--transition);
}
.product-card:hover .product-icon {
  background: linear-gradient(135deg, var(--primary), var(--accent));
  color: #fff; transform: scale(1.08);
}
.product-name { font-size: 19px; font-weight: 700; color: var(--text-dark); margin-bottom: 10px; }
.product-desc { font-size: 14px; color: var(--text-muted); line-height: 1.7; margin-bottom: 18px; }
.product-features { display: flex; flex-wrap: wrap; gap: 8px; }
.feature-tag {
  padding: 3px 10px; background: rgba(26,111,196,0.07);
  color: var(--primary); border-radius: 4px; font-size: 12px; font-weight: 500;
}

/* ===== 优势特色 ===== */
.advantages-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
.advantage-card {
  text-align: center; padding: 36px 20px;
  background: var(--bg-white); border-radius: var(--radius-lg);
  border: 1px solid var(--border); transition: all var(--transition);
}
.advantage-card:hover { transform: translateY(-4px); box-shadow: var(--shadow); }
.advantage-icon {
  width: 72px; height: 72px; margin: 0 auto 20px;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  border-radius: 50%; display: flex; align-items: center; justify-content: center;
  font-size: 30px; color: #fff;
}
.advantage-title { font-size: 17px; font-weight: 700; color: var(--text-dark); margin-bottom: 10px; }
.advantage-desc { font-size: 13px; color: var(--text-muted); line-height: 1.7; }

/* ===== 流程步骤 ===== */
.process-steps { display: flex; align-items: flex-start; gap: 0; position: relative; }
.process-steps::before {
  content: ''; position: absolute;
  top: 36px; left: calc(12.5%);
  right: calc(12.5%); height: 2px;
  background: linear-gradient(90deg, var(--primary), var(--accent));
  z-index: 0;
}
.process-step {
  flex: 1; text-align: center; padding: 0 12px; position: relative; z-index: 1;
}
.step-circle {
  width: 72px; height: 72px; border-radius: 50%;
  background: var(--primary); color: #fff;
  display: flex; align-items: center; justify-content: center;
  font-size: 26px; margin: 0 auto 16px;
  box-shadow: 0 4px 16px rgba(26,111,196,0.3);
  position: relative;
}
.step-number {
  position: absolute; top: -4px; right: -4px;
  width: 22px; height: 22px; background: var(--accent);
  border-radius: 50%; font-size: 11px; font-weight: 700;
  display: flex; align-items: center; justify-content: center;
}
.step-title { font-size: 15px; font-weight: 700; color: var(--text-dark); margin-bottom: 8px; }
.step-desc { font-size: 13px; color: var(--text-muted); line-height: 1.6; }

/* ===== 合作伙伴 ===== */
.partners-slider { overflow: hidden; }
.partners-track {
  display: flex; gap: 24px;
  animation: scroll 25s linear infinite;
}
.partner-logo {
  flex-shrink: 0;
  padding: 16px 28px; background: var(--bg-white);
  border: 1px solid var(--border); border-radius: var(--radius);
  display: flex; align-items: center; justify-content: center;
  font-size: 15px; font-weight: 600; color: var(--text-muted);
  white-space: nowrap; min-width: 150px;
  transition: all var(--transition);
}
.partner-logo:hover { border-color: var(--primary); color: var(--primary); }

@keyframes scroll { 0% { transform: translateX(0); } 100% { transform: translateX(-50%); } }

/* ===== 新闻动态 ===== */
.news-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 28px; }
.news-card {
  background: var(--bg-white); border-radius: var(--radius-lg);
  overflow: hidden; border: 1px solid var(--border);
  transition: all var(--transition);
}
.news-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); }
.news-cover { height: 180px; background: linear-gradient(135deg, var(--primary), var(--accent)); position: relative; overflow: hidden; }
.news-cover img { width: 100%; height: 100%; object-fit: cover; }
.news-cover-placeholder { width: 100%; height: 100%; display: flex; align-items: center; justify-content: center; color: rgba(255,255,255,0.4); font-size: 48px; }
.news-body { padding: 24px; }
.news-date { font-size: 12px; color: var(--text-muted); margin-bottom: 10px; }
.news-title { font-size: 16px; font-weight: 700; color: var(--text-dark); margin-bottom: 10px; line-height: 1.4; }
.news-summary { font-size: 13px; color: var(--text-muted); line-height: 1.7; }
.news-more { margin-top: 16px; font-size: 13px; font-weight: 600; color: var(--primary); display: flex; align-items: center; gap: 4px; }

/* ===== CTA条幅 ===== */
.cta-section {
  background: linear-gradient(135deg, var(--primary-dark), var(--primary), var(--accent));
  padding: 72px 0; text-align: center; color: #fff;
}
.cta-title { font-size: 36px; font-weight: 800; margin-bottom: 12px; }
.cta-subtitle { font-size: 17px; opacity: 0.85; margin-bottom: 36px; }
.cta-actions { display: flex; gap: 16px; justify-content: center; flex-wrap: wrap; }
.btn-cta-white {
  padding: 14px 36px; background: #fff; color: var(--primary) !important;
  border-radius: 8px; font-size: 16px; font-weight: 700;
  box-shadow: 0 4px 20px rgba(0,0,0,0.15);
  transition: all var(--transition);
}
.btn-cta-white:hover { transform: translateY(-2px); box-shadow: 0 8px 30px rgba(0,0,0,0.2); }
.btn-cta-outline {
  padding: 14px 36px; border: 2px solid rgba(255,255,255,0.6); color: #fff !important;
  border-radius: 8px; font-size: 16px; font-weight: 600;
  transition: all var(--transition);
}
.btn-cta-outline:hover { background: rgba(255,255,255,0.12); }

/* ===== 页脚 ===== */
.footer {
  background: #0d1b2a; color: rgba(255,255,255,0.7);
  padding: 60px 0 0;
}
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr 1.5fr; gap: 48px; padding-bottom: 48px; }
.footer-brand .logo-name { color: #fff; }
.footer-brand .logo-slogan { color: rgba(255,255,255,0.5); }
.footer-desc { font-size: 13px; line-height: 1.8; margin: 16px 0 20px; opacity: 0.7; }
.footer-social { display: flex; gap: 10px; }
.social-icon {
  width: 36px; height: 36px; background: rgba(255,255,255,0.1);
  border-radius: 8px; display: flex; align-items: center; justify-content: center;
  color: rgba(255,255,255,0.7); font-size: 16px; transition: all var(--transition);
}
.social-icon:hover { background: var(--primary); color: #fff; }

.footer-col-title { font-size: 15px; font-weight: 700; color: #fff; margin-bottom: 20px; padding-bottom: 10px; border-bottom: 1px solid rgba(255,255,255,0.1); }
.footer-links { display: flex; flex-direction: column; gap: 10px; }
.footer-links a { font-size: 13px; color: rgba(255,255,255,0.6); transition: color var(--transition); }
.footer-links a:hover { color: #fff; }

.footer-contact { display: flex; flex-direction: column; gap: 12px; }
.contact-item { display: flex; align-items: flex-start; gap: 10px; font-size: 13px; }
.contact-item i { color: var(--accent); margin-top: 2px; flex-shrink: 0; }

.footer-bottom {
  border-top: 1px solid rgba(255,255,255,0.08);
  padding: 20px 0; text-align: center; font-size: 12px; color: rgba(255,255,255,0.4);
}
.footer-bottom a { color: rgba(255,255,255,0.5); }
.footer-bottom a:hover { color: rgba(255,255,255,0.8); }

/* ===== 关于我们页面 ===== */
.page-hero {
  padding: calc(var(--header-h) + 60px) 0 80px;
  background: linear-gradient(135deg, #0a2744 0%, #1a6fc4 100%);
  color: #fff; text-align: center;
}
.page-hero-title { font-size: 44px; font-weight: 800; margin-bottom: 12px; }
.page-hero-subtitle { font-size: 18px; opacity: 0.8; }
.breadcrumb { display: flex; align-items: center; gap: 8px; font-size: 13px; opacity: 0.7; margin-bottom: 20px; justify-content: center; }
.breadcrumb a { color: rgba(255,255,255,0.7); }
.breadcrumb i { font-size: 10px; }

.about-intro { display: grid; grid-template-columns: 1fr 1fr; gap: 64px; align-items: center; }
.about-intro-text h2 { font-size: 34px; font-weight: 800; color: var(--text-dark); margin-bottom: 20px; }
.about-intro-text p { font-size: 16px; color: var(--text-muted); line-height: 1.8; margin-bottom: 16px; }
.about-visual { position: relative; }
.about-image-box {
  background: linear-gradient(135deg, var(--primary), var(--accent));
  border-radius: var(--radius-lg); padding: 48px;
  display: flex; align-items: center; justify-content: center;
  min-height: 340px; color: #fff;
}
.about-logo-large { width: 160px; filter: brightness(0) invert(1); }
.about-stats-overlay {
  position: absolute; bottom: -24px; right: -24px;
  background: #fff; border-radius: var(--radius-lg); padding: 24px 28px;
  box-shadow: var(--shadow-lg); display: grid; grid-template-columns: 1fr 1fr; gap: 20px;
}
.about-stat { text-align: center; }
.about-stat-num { font-size: 28px; font-weight: 800; color: var(--primary); }
.about-stat-label { font-size: 12px; color: var(--text-muted); }

.milestones { position: relative; }
.milestone-line { position: absolute; left: 50%; top: 0; bottom: 0; width: 2px; background: linear-gradient(180deg, var(--primary), var(--accent)); transform: translateX(-50%); }
.milestone-item {
  display: grid; grid-template-columns: 1fr 60px 1fr; gap: 24px;
  align-items: center; margin-bottom: 40px;
}
.milestone-content {
  background: var(--bg-white); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 20px 24px;
  box-shadow: var(--shadow);
}
.milestone-content.right { text-align: right; }
.milestone-year { font-size: 22px; font-weight: 800; color: var(--primary); }
.milestone-title { font-size: 15px; font-weight: 700; color: var(--text-dark); margin-bottom: 4px; }
.milestone-desc { font-size: 13px; color: var(--text-muted); }
.milestone-dot { width: 16px; height: 16px; background: var(--primary); border-radius: 50%; margin: 0 auto; border: 3px solid #fff; box-shadow: 0 0 0 3px var(--primary); z-index: 1; position: relative; }

/* ===== 产品服务页 ===== */
.products-page-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 28px; }
.product-page-card {
  background: var(--bg-white); border-radius: var(--radius-lg);
  border: 1px solid var(--border); overflow: hidden;
  transition: all var(--transition); display: flex;
}
.product-page-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); }
.product-page-icon-col {
  width: 100px; flex-shrink: 0;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  display: flex; align-items: center; justify-content: center;
  font-size: 40px; color: #fff;
}
.product-page-body { padding: 28px 24px; }
.product-page-category { font-size: 11px; font-weight: 600; color: var(--accent); letter-spacing: 1px; text-transform: uppercase; margin-bottom: 6px; }
.product-page-name { font-size: 20px; font-weight: 800; color: var(--text-dark); margin-bottom: 10px; }
.product-page-desc { font-size: 14px; color: var(--text-muted); line-height: 1.7; margin-bottom: 16px; }

/* ===== 联系我们页 ===== */
.contact-grid { display: grid; grid-template-columns: 1fr 1.5fr; gap: 48px; align-items: start; }
.contact-info-card {
  background: var(--bg-white); border-radius: var(--radius-lg);
  border: 1px solid var(--border); padding: 36px; box-shadow: var(--shadow);
}
.contact-info-item { display: flex; align-items: flex-start; gap: 16px; padding: 18px 0; border-bottom: 1px solid var(--border); }
.contact-info-item:last-child { border-bottom: none; }
.contact-info-icon {
  width: 46px; height: 46px; flex-shrink: 0;
  background: linear-gradient(135deg, rgba(26,111,196,0.1), rgba(0,180,216,0.1));
  border-radius: 10px; display: flex; align-items: center; justify-content: center;
  font-size: 20px; color: var(--primary);
}
.contact-info-label { font-size: 12px; color: var(--text-muted); margin-bottom: 4px; }
.contact-info-value { font-size: 16px; font-weight: 600; color: var(--text-dark); }

.contact-form-card {
  background: var(--bg-white); border-radius: var(--radius-lg);
  border: 1px solid var(--border); padding: 36px; box-shadow: var(--shadow);
}
.form-title { font-size: 20px; font-weight: 700; color: var(--text-dark); margin-bottom: 24px; }
.form-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.form-group { margin-bottom: 16px; }
.form-group.full { grid-column: 1 / -1; }
.form-label { display: block; font-size: 13px; font-weight: 600; color: var(--text-dark); margin-bottom: 6px; }
.form-label span { color: #ef4444; }
.form-control {
  width: 100%; padding: 11px 14px;
  border: 1.5px solid var(--border); border-radius: 8px;
  font-size: 14px; color: var(--text-dark);
  background: var(--bg-white);
  transition: border-color var(--transition), box-shadow var(--transition);
  outline: none; font-family: inherit;
}
.form-control:focus { border-color: var(--primary); box-shadow: 0 0 0 3px rgba(26,111,196,0.1); }
textarea.form-control { resize: vertical; min-height: 120px; }
.btn-submit {
  width: 100%; padding: 14px; background: linear-gradient(135deg, var(--primary), var(--accent));
  color: #fff !important; border: none; border-radius: 8px; font-size: 16px; font-weight: 700;
  cursor: pointer; transition: all var(--transition); box-shadow: 0 4px 16px rgba(26,111,196,0.3);
  display: flex; align-items: center; justify-content: center; gap: 8px;
}
.btn-submit:hover { opacity: 0.9; transform: translateY(-1px); box-shadow: 0 6px 20px rgba(26,111,196,0.4); }
.form-success {
  display: none; padding: 16px; background: #ecfdf5; border: 1px solid #10b981;
  border-radius: 8px; color: #059669; font-weight: 600; margin-top: 12px;
  text-align: center;
}
.form-error {
  display: none; padding: 16px; background: #fef2f2; border: 1px solid #ef4444;
  border-radius: 8px; color: #dc2626; font-size: 13px; margin-top: 8px;
}

/* ===== 动画 ===== */
@keyframes fadeIn { from { opacity: 0; transform: translateY(16px); } to { opacity: 1; transform: translateY(0); } }
@keyframes countUp { from { opacity: 0; transform: translateY(10px); } to { opacity: 1; transform: translateY(0); } }

.fade-in { opacity: 0; transform: translateY(24px); transition: opacity 0.6s ease, transform 0.6s ease; }
.fade-in.visible { opacity: 1; transform: translateY(0); }
.fade-in-delay-1 { transition-delay: 0.1s; }
.fade-in-delay-2 { transition-delay: 0.2s; }
.fade-in-delay-3 { transition-delay: 0.3s; }
.fade-in-delay-4 { transition-delay: 0.4s; }

/* ===== 响应式 ===== */
@media (max-width: 992px) {
  .hero-slide { flex-direction: column; text-align: center; }
  .hero-title { font-size: 36px; }
  .hero-visual { margin-top: 40px; }
  .products-grid { grid-template-columns: repeat(2, 1fr); }
  .advantages-grid { grid-template-columns: repeat(2, 1fr); }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: 1fr 1fr; gap: 32px; }
  .about-intro { grid-template-columns: 1fr; }
  .about-stats-overlay { position: relative; bottom: auto; right: auto; margin-top: 20px; }
  .contact-grid { grid-template-columns: 1fr; }
  .products-page-grid { grid-template-columns: 1fr; }
}

@media (max-width: 768px) {
  .nav { display: none; }
  .menu-toggle { display: flex; }
  .header-cta .btn-header-phone { display: none; }
  .products-grid { grid-template-columns: 1fr; }
  .advantages-grid { grid-template-columns: 1fr 1fr; }
  .process-steps { flex-direction: column; }
  .process-steps::before { display: none; }
  .footer-grid { grid-template-columns: 1fr; }
  .hero-actions { flex-direction: column; align-items: flex-start; }
  .cta-actions { flex-direction: column; align-items: center; }
  .form-grid { grid-template-columns: 1fr; }
  .news-grid { grid-template-columns: 1fr; }

  .nav.open {
    display: flex; flex-direction: column;
    position: absolute; top: var(--header-h); left: 0; right: 0;
    background: #fff; border-bottom: 1px solid var(--border);
    padding: 16px; box-shadow: var(--shadow-lg);
  }
}

@media (max-width: 480px) {
  .section { padding: 56px 0; }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .advantages-grid { grid-template-columns: 1fr; }
}

/* ===== 回到顶部按钮 ===== */
.back-to-top {
  position: fixed; bottom: 32px; right: 32px; z-index: 999;
  width: 44px; height: 44px; background: var(--primary);
  border-radius: 50%; display: flex; align-items: center; justify-content: center;
  color: #fff; font-size: 18px; cursor: pointer;
  box-shadow: 0 4px 16px rgba(26,111,196,0.3);
  opacity: 0; pointer-events: none; transition: all var(--transition);
  border: none;
}
.back-to-top.visible { opacity: 1; pointer-events: auto; }
.back-to-top:hover { transform: translateY(-3px); box-shadow: 0 6px 20px rgba(26,111,196,0.4); }