/* ============================================
   开云体育官网 - 主样式文件
   KAIYUN Sports - asi-login-kaiyungame.com
   ============================================ */

/* ---- CSS Reset & Base ---- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { font-size: 16px; scroll-behavior: smooth; }
body {
  font-family: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", Arial, sans-serif;
  color: #1a1a2e;
  background: #fff;
  line-height: 1.7;
  overflow-x: hidden;
}
a { color: inherit; text-decoration: none; }
img { max-width: 100%; height: auto; display: block; }
ul, ol { list-style: none; }

/* ---- CSS Variables ---- */
:root {
  --primary: #e63946;
  --primary-dark: #c1121f;
  --secondary: #1d3557;
  --accent: #f4a261;
  --bg-dark: #0d1b2a;
  --bg-light: #f8f9fa;
  --text-main: #1a1a2e;
  --text-muted: #6c757d;
  --border: #dee2e6;
  --shadow: 0 4px 20px rgba(0,0,0,0.1);
  --shadow-lg: 0 8px 40px rgba(0,0,0,0.15);
  --radius: 8px;
  --radius-lg: 16px;
  --transition: 0.3s ease;
  --max-width: 1200px;
}

/* ---- Container ---- */
.container { max-width: var(--max-width); margin: 0 auto; padding: 0 20px; }
.section { padding: 80px 0; }
.section-sm { padding: 50px 0; }
.section-title {
  font-size: 2rem;
  font-weight: 700;
  color: var(--secondary);
  text-align: center;
  margin-bottom: 12px;
  position: relative;
}
.section-title span { color: var(--primary); }
.section-subtitle {
  text-align: center;
  color: var(--text-muted);
  font-size: 1rem;
  margin-bottom: 50px;
}
.section-title::after {
  content: '';
  display: block;
  width: 60px;
  height: 4px;
  background: linear-gradient(90deg, var(--primary), var(--accent));
  margin: 14px auto 0;
  border-radius: 2px;
}

/* ---- Header & Navigation ---- */
#header {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 1000;
  background: rgba(13,27,42,0.97);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid rgba(255,255,255,0.08);
  transition: var(--transition);
}
#header.scrolled { box-shadow: var(--shadow-lg); }
.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 70px;
  gap: 20px;
}
.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-shrink: 0;
}
.logo-icon {
  width: 42px; height: 42px;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  border-radius: 10px;
  display: flex; align-items: center; justify-content: center;
  font-size: 1.4rem; font-weight: 900; color: #fff;
  letter-spacing: -1px;
}
.logo-text { color: #fff; font-size: 1.2rem; font-weight: 700; line-height: 1.2; }
.logo-text small { display: block; font-size: 0.65rem; font-weight: 400; color: rgba(255,255,255,0.6); letter-spacing: 1px; }

/* Main Nav */
.main-nav { display: flex; align-items: center; gap: 4px; }
.main-nav a {
  color: rgba(255,255,255,0.85);
  font-size: 0.9rem;
  padding: 8px 14px;
  border-radius: var(--radius);
  transition: var(--transition);
  white-space: nowrap;
}
.main-nav a:hover, .main-nav a.active {
  color: #fff;
  background: rgba(230,57,70,0.2);
}
.nav-cta {
  background: var(--primary) !important;
  color: #fff !important;
  padding: 8px 18px !important;
  border-radius: 20px !important;
}
.nav-cta:hover { background: var(--primary-dark) !important; }

/* Mobile Menu Toggle */
.menu-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  cursor: pointer;
  padding: 4px;
}
.menu-toggle span {
  width: 24px; height: 2px;
  background: #fff;
  border-radius: 2px;
  transition: var(--transition);
}

/* Search Bar */
.search-bar {
  display: flex;
  align-items: center;
  background: rgba(255,255,255,0.1);
  border: 1px solid rgba(255,255,255,0.15);
  border-radius: 20px;
  padding: 6px 14px;
  gap: 8px;
  min-width: 200px;
}
.search-bar input {
  background: none;
  border: none;
  outline: none;
  color: #fff;
  font-size: 0.85rem;
  width: 100%;
}
.search-bar input::placeholder { color: rgba(255,255,255,0.5); }
.search-bar button {
  background: none;
  border: none;
  cursor: pointer;
  color: rgba(255,255,255,0.7);
  font-size: 0.9rem;
  padding: 0;
  transition: var(--transition);
}
.search-bar button:hover { color: var(--primary); }

/* ---- Hero Banner / Slider ---- */
#hero {
  position: relative;
  height: 100vh;
  min-height: 600px;
  max-height: 900px;
  overflow: hidden;
  margin-top: 70px;
}
.hero-slides { position: relative; width: 100%; height: 100%; }
.hero-slide {
  position: absolute;
  inset: 0;
  opacity: 0;
  transition: opacity 1s ease;
  background-size: cover;
  background-position: center;
}
.hero-slide.active { opacity: 1; }
.hero-slide::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(13,27,42,0.85) 0%, rgba(13,27,42,0.4) 60%, transparent 100%);
}
.hero-content {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 100%;
  max-width: 800px;
  padding: 0 30px;
  text-align: center;
  color: #fff;
}
.hero-badge {
  display: inline-block;
  background: var(--primary);
  color: #fff;
  font-size: 0.75rem;
  font-weight: 600;
  padding: 4px 14px;
  border-radius: 20px;
  margin-bottom: 20px;
  letter-spacing: 1px;
  text-transform: uppercase;
}
.hero-title {
  font-size: clamp(2rem, 5vw, 3.5rem);
  font-weight: 900;
  line-height: 1.2;
  margin-bottom: 20px;
  text-shadow: 0 2px 20px rgba(0,0,0,0.5);
}
.hero-title span { color: var(--accent); }
.hero-desc {
  font-size: clamp(0.95rem, 2vw, 1.1rem);
  color: rgba(255,255,255,0.85);
  margin-bottom: 35px;
  max-width: 600px;
  margin-left: auto;
  margin-right: auto;
}
.hero-btns { display: flex; gap: 16px; justify-content: center; flex-wrap: wrap; }
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 32px;
  border-radius: 30px;
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
  border: none;
  transition: var(--transition);
  text-decoration: none;
}
.btn-primary { background: var(--primary); color: #fff; }
.btn-primary:hover { background: var(--primary-dark); transform: translateY(-2px); box-shadow: 0 8px 25px rgba(230,57,70,0.4); }
.btn-outline { background: transparent; color: #fff; border: 2px solid rgba(255,255,255,0.6); }
.btn-outline:hover { background: rgba(255,255,255,0.1); border-color: #fff; }
.btn-secondary { background: var(--secondary); color: #fff; }
.btn-secondary:hover { background: #16304a; transform: translateY(-2px); }

/* Hero Stats */
.hero-stats {
  position: absolute;
  bottom: 40px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  gap: 40px;
  color: #fff;
}
.hero-stat { text-align: center; }
.hero-stat-num { font-size: 1.8rem; font-weight: 800; color: var(--accent); }
.hero-stat-label { font-size: 0.75rem; color: rgba(255,255,255,0.7); margin-top: 2px; }

/* Slider Controls */
.slider-dots {
  position: absolute;
  bottom: 20px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  gap: 8px;
}
.slider-dot {
  width: 8px; height: 8px;
  border-radius: 50%;
  background: rgba(255,255,255,0.4);
  cursor: pointer;
  transition: var(--transition);
}
.slider-dot.active { background: var(--primary); width: 24px; border-radius: 4px; }

/* ---- Video Grid Section ---- */
#videos { background: var(--bg-dark); }
#videos .section-title { color: #fff; }
#videos .section-subtitle { color: rgba(255,255,255,0.6); }
.video-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 24px;
}
.video-card {
  background: rgba(255,255,255,0.05);
  border-radius: var(--radius-lg);
  overflow: hidden;
  border: 1px solid rgba(255,255,255,0.08);
  transition: var(--transition);
  cursor: pointer;
}
.video-card:hover { transform: translateY(-6px); box-shadow: 0 12px 40px rgba(0,0,0,0.4); border-color: var(--primary); }
.video-thumb {
  position: relative;
  aspect-ratio: 16/9;
  overflow: hidden;
}
.video-thumb img { width: 100%; height: 100%; object-fit: cover; transition: transform 0.5s ease; }
.video-card:hover .video-thumb img { transform: scale(1.08); }
.video-play-btn {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(0,0,0,0.3);
  opacity: 0;
  transition: var(--transition);
}
.video-card:hover .video-play-btn { opacity: 1; }
.play-icon {
  width: 60px; height: 60px;
  background: rgba(230,57,70,0.9);
  border-radius: 50%;
  display: flex; align-items: center; justify-content: center;
  transform: scale(0.8);
  transition: var(--transition);
}
.video-card:hover .play-icon { transform: scale(1); }
.play-icon::after {
  content: '';
  border-left: 20px solid #fff;
  border-top: 12px solid transparent;
  border-bottom: 12px solid transparent;
  margin-left: 4px;
}
.video-tag {
  position: absolute;
  top: 10px; left: 10px;
  background: var(--primary);
  color: #fff;
  font-size: 0.7rem;
  font-weight: 600;
  padding: 3px 10px;
  border-radius: 4px;
  text-transform: uppercase;
}
.video-duration {
  position: absolute;
  bottom: 8px; right: 8px;
  background: rgba(0,0,0,0.7);
  color: #fff;
  font-size: 0.75rem;
  padding: 2px 8px;
  border-radius: 4px;
}
.video-info { padding: 16px; }
.video-title {
  color: #fff;
  font-size: 0.95rem;
  font-weight: 600;
  margin-bottom: 8px;
  line-height: 1.4;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}
.video-meta {
  display: flex;
  gap: 16px;
  color: rgba(255,255,255,0.5);
  font-size: 0.8rem;
}
.video-meta span { display: flex; align-items: center; gap: 4px; }

/* ---- About Section ---- */
#about { background: var(--bg-light); }
.about-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 60px; align-items: center; }
.about-img { border-radius: var(--radius-lg); overflow: hidden; box-shadow: var(--shadow-lg); }
.about-content .section-title { text-align: left; }
.about-content .section-title::after { margin-left: 0; }
.about-desc { color: var(--text-muted); margin-bottom: 30px; line-height: 1.8; }
.about-features { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; margin-bottom: 30px; }
.feature-item {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  padding: 16px;
  background: #fff;
  border-radius: var(--radius);
  border-left: 3px solid var(--primary);
}
.feature-icon { font-size: 1.5rem; flex-shrink: 0; }
.feature-text h4 { font-size: 0.9rem; font-weight: 600; color: var(--secondary); margin-bottom: 4px; }
.feature-text p { font-size: 0.8rem; color: var(--text-muted); }

/* ---- Services Section ---- */
#services { background: #fff; }
.services-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); gap: 28px; }
.service-card {
  background: #fff;
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow);
  transition: var(--transition);
  border: 1px solid var(--border);
}
.service-card:hover { transform: translateY(-6px); box-shadow: var(--shadow-lg); border-color: var(--primary); }
.service-img { aspect-ratio: 4/3; overflow: hidden; }
.service-img img { width: 100%; height: 100%; object-fit: cover; transition: transform 0.5s ease; }
.service-card:hover .service-img img { transform: scale(1.05); }
.service-body { padding: 24px; }
.service-icon { font-size: 2rem; margin-bottom: 12px; }
.service-title { font-size: 1.1rem; font-weight: 700; color: var(--secondary); margin-bottom: 10px; }
.service-desc { font-size: 0.875rem; color: var(--text-muted); line-height: 1.7; }
.service-tags { display: flex; flex-wrap: wrap; gap: 6px; margin-top: 14px; }
.service-tag {
  background: rgba(230,57,70,0.08);
  color: var(--primary);
  font-size: 0.72rem;
  padding: 3px 10px;
  border-radius: 20px;
  border: 1px solid rgba(230,57,70,0.2);
}

/* ---- Cases Section ---- */
#cases { background: var(--bg-light); }
.cases-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(340px, 1fr)); gap: 28px; }
.case-card {
  background: #fff;
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow);
  transition: var(--transition);
}
.case-card:hover { transform: translateY(-6px); box-shadow: var(--shadow-lg); }
.case-img { aspect-ratio: 16/9; overflow: hidden; position: relative; }
.case-img img { width: 100%; height: 100%; object-fit: cover; transition: transform 0.5s ease; }
.case-card:hover .case-img img { transform: scale(1.05); }
.case-category {
  position: absolute;
  top: 12px; left: 12px;
  background: var(--secondary);
  color: #fff;
  font-size: 0.72rem;
  padding: 4px 12px;
  border-radius: 4px;
}
.case-body { padding: 24px; }
.case-title { font-size: 1rem; font-weight: 700; color: var(--secondary); margin-bottom: 10px; }
.case-desc { font-size: 0.85rem; color: var(--text-muted); margin-bottom: 16px; }
.case-stats { display: flex; gap: 20px; }
.case-stat { text-align: center; }
.case-stat-num { font-size: 1.3rem; font-weight: 800; color: var(--primary); }
.case-stat-label { font-size: 0.72rem; color: var(--text-muted); }

/* ---- News Section ---- */
#news { background: #fff; }
.news-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(300px, 1fr)); gap: 28px; }
.news-card {
  background: #fff;
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow);
  border: 1px solid var(--border);
  transition: var(--transition);
}
.news-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); }
.news-img { aspect-ratio: 16/9; overflow: hidden; }
.news-img img { width: 100%; height: 100%; object-fit: cover; transition: transform 0.5s ease; }
.news-card:hover .news-img img { transform: scale(1.05); }
.news-body { padding: 20px; }
.news-meta { display: flex; gap: 12px; margin-bottom: 10px; }
.news-cat {
  background: rgba(230,57,70,0.1);
  color: var(--primary);
  font-size: 0.72rem;
  padding: 2px 10px;
  border-radius: 4px;
  font-weight: 600;
}
.news-date { font-size: 0.75rem; color: var(--text-muted); }
.news-title { font-size: 0.95rem; font-weight: 700; color: var(--secondary); margin-bottom: 8px; line-height: 1.5; }
.news-excerpt { font-size: 0.82rem; color: var(--text-muted); line-height: 1.6; }
.news-more { margin-top: 12px; font-size: 0.82rem; color: var(--primary); font-weight: 600; }
.news-more:hover { text-decoration: underline; }

/* ---- Reviews Section ---- */
#reviews { background: var(--bg-dark); }
#reviews .section-title { color: #fff; }
#reviews .section-subtitle { color: rgba(255,255,255,0.6); }
.reviews-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); gap: 24px; }
.review-card {
  background: rgba(255,255,255,0.06);
  border: 1px solid rgba(255,255,255,0.1);
  border-radius: var(--radius-lg);
  padding: 28px;
  transition: var(--transition);
}
.review-card:hover { background: rgba(255,255,255,0.1); transform: translateY(-4px); }
.review-stars { color: var(--accent); font-size: 1rem; margin-bottom: 14px; letter-spacing: 2px; }
.review-text { color: rgba(255,255,255,0.85); font-size: 0.9rem; line-height: 1.7; margin-bottom: 20px; font-style: italic; }
.review-author { display: flex; align-items: center; gap: 12px; }
.review-avatar {
  width: 44px; height: 44px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  display: flex; align-items: center; justify-content: center;
  color: #fff;
  font-size: 1rem;
  font-weight: 700;
  flex-shrink: 0;
}
.review-name { color: #fff; font-weight: 600; font-size: 0.9rem; }
.review-role { color: rgba(255,255,255,0.5); font-size: 0.78rem; }

/* ---- FAQ Section ---- */
#faq { background: var(--bg-light); }
.faq-list { max-width: 800px; margin: 0 auto; }
.faq-item {
  background: #fff;
  border-radius: var(--radius);
  margin-bottom: 12px;
  border: 1px solid var(--border);
  overflow: hidden;
}
.faq-question {
  width: 100%;
  text-align: left;
  padding: 20px 24px;
  background: none;
  border: none;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--secondary);
  transition: var(--transition);
}
.faq-question:hover { color: var(--primary); }
.faq-question.active { color: var(--primary); }
.faq-arrow {
  width: 20px; height: 20px;
  border-radius: 50%;
  background: rgba(230,57,70,0.1);
  display: flex; align-items: center; justify-content: center;
  transition: var(--transition);
  flex-shrink: 0;
  font-size: 0.7rem;
  color: var(--primary);
}
.faq-question.active .faq-arrow { transform: rotate(180deg); background: var(--primary); color: #fff; }
.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.4s ease, padding 0.3s ease;
}
.faq-answer.open { max-height: 300px; }
.faq-answer-inner {
  padding: 0 24px 20px;
  font-size: 0.875rem;
  color: var(--text-muted);
  line-height: 1.8;
  border-top: 1px solid var(--border);
  padding-top: 16px;
}

/* ---- Partners Section ---- */
#partners { background: #fff; }
.partners-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
  gap: 20px;
  margin-bottom: 50px;
}
.partner-logo {
  background: var(--bg-light);
  border-radius: var(--radius);
  padding: 20px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--text-muted);
  border: 1px solid var(--border);
  transition: var(--transition);
  min-height: 80px;
  text-align: center;
}
.partner-logo:hover { border-color: var(--primary); color: var(--primary); background: rgba(230,57,70,0.04); }

/* ---- Contact Section ---- */
#contact { background: var(--bg-light); }
.contact-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 60px; }
.contact-info h3 { font-size: 1.3rem; color: var(--secondary); margin-bottom: 24px; }
.contact-item {
  display: flex;
  align-items: flex-start;
  gap: 14px;
  margin-bottom: 20px;
  padding: 16px;
  background: #fff;
  border-radius: var(--radius);
  border: 1px solid var(--border);
}
.contact-icon {
  width: 40px; height: 40px;
  background: rgba(230,57,70,0.1);
  border-radius: 8px;
  display: flex; align-items: center; justify-content: center;
  font-size: 1.1rem;
  flex-shrink: 0;
}
.contact-label { font-size: 0.78rem; color: var(--text-muted); margin-bottom: 2px; }
.contact-value { font-size: 0.9rem; font-weight: 600; color: var(--secondary); }
.map-placeholder {
  background: linear-gradient(135deg, #e8f4fd, #d1ecf1);
  border-radius: var(--radius-lg);
  height: 300px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  color: var(--text-muted);
  font-size: 0.9rem;
  border: 2px dashed var(--border);
  gap: 10px;
}
.map-placeholder .map-icon { font-size: 3rem; }

/* ---- Footer ---- */
#footer {
  background: var(--bg-dark);
  color: rgba(255,255,255,0.7);
  padding: 60px 0 0;
}
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 40px; margin-bottom: 40px; }
.footer-brand .logo { margin-bottom: 16px; }
.footer-brand p { font-size: 0.85rem; line-height: 1.8; margin-bottom: 20px; }
.footer-social { display: flex; gap: 10px; }
.social-btn {
  width: 36px; height: 36px;
  background: rgba(255,255,255,0.08);
  border-radius: 8px;
  display: flex; align-items: center; justify-content: center;
  font-size: 0.85rem;
  transition: var(--transition);
  cursor: pointer;
}
.social-btn:hover { background: var(--primary); }
.footer-col h4 { color: #fff; font-size: 0.95rem; margin-bottom: 16px; }
.footer-col ul li { margin-bottom: 10px; }
.footer-col ul li a { font-size: 0.85rem; transition: var(--transition); }
.footer-col ul li a:hover { color: var(--primary); padding-left: 4px; }
.footer-qr { display: flex; gap: 20px; }
.qr-item { text-align: center; }
.qr-box {
  width: 80px; height: 80px;
  background: rgba(255,255,255,0.1);
  border-radius: 8px;
  display: flex; align-items: center; justify-content: center;
  font-size: 0.6rem;
  color: rgba(255,255,255,0.5);
  margin-bottom: 6px;
  border: 1px dashed rgba(255,255,255,0.2);
}
.qr-label { font-size: 0.72rem; color: rgba(255,255,255,0.5); }
.footer-bottom {
  border-top: 1px solid rgba(255,255,255,0.08);
  padding: 20px 0;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
  font-size: 0.8rem;
}
.footer-bottom a:hover { color: var(--primary); }

/* ---- Breadcrumb ---- */
.breadcrumb {
  background: var(--bg-light);
  padding: 14px 0;
  margin-top: 70px;
  border-bottom: 1px solid var(--border);
}
.breadcrumb-list { display: flex; align-items: center; gap: 8px; font-size: 0.85rem; color: var(--text-muted); }
.breadcrumb-list a:hover { color: var(--primary); }
.breadcrumb-list .sep { color: var(--border); }
.breadcrumb-list .current { color: var(--secondary); font-weight: 600; }

/* ---- Page Hero (inner pages) ---- */
.page-hero {
  background: linear-gradient(135deg, var(--bg-dark) 0%, var(--secondary) 100%);
  padding: 80px 0 60px;
  margin-top: 70px;
  color: #fff;
  text-align: center;
}
.page-hero h1 { font-size: clamp(1.8rem, 4vw, 2.8rem); font-weight: 800; margin-bottom: 14px; }
.page-hero p { font-size: 1rem; color: rgba(255,255,255,0.75); max-width: 600px; margin: 0 auto; }

/* ---- Stats Bar ---- */
.stats-bar {
  background: var(--primary);
  padding: 30px 0;
}
.stats-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; text-align: center; }
.stat-item { color: #fff; }
.stat-num { font-size: 2rem; font-weight: 900; display: block; }
.stat-label { font-size: 0.8rem; opacity: 0.85; }

/* ---- Scroll to Top ---- */
#scrollTop {
  position: fixed;
  bottom: 30px; right: 30px;
  width: 44px; height: 44px;
  background: var(--primary);
  color: #fff;
  border: none;
  border-radius: 50%;
  cursor: pointer;
  font-size: 1.1rem;
  display: none;
  align-items: center;
  justify-content: center;
  box-shadow: var(--shadow);
  transition: var(--transition);
  z-index: 999;
}
#scrollTop.show { display: flex; }
#scrollTop:hover { background: var(--primary-dark); transform: translateY(-3px); }

/* ---- Lazy Load ---- */
img[data-src] { opacity: 0; transition: opacity 0.4s ease; }
img.loaded { opacity: 1; }

/* ---- Responsive ---- */
@media (max-width: 1024px) {
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .about-grid { grid-template-columns: 1fr; }
  .contact-grid { grid-template-columns: 1fr; }
}
@media (max-width: 768px) {
  .section { padding: 60px 0; }
  .main-nav { display: none; position: absolute; top: 70px; left: 0; right: 0; background: rgba(13,27,42,0.98); flex-direction: column; padding: 20px; gap: 4px; }
  .main-nav.open { display: flex; }
  .main-nav a { padding: 12px 16px; border-radius: var(--radius); }
  .menu-toggle { display: flex; }
  .search-bar { min-width: 140px; }
  .hero-stats { gap: 20px; }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: 1fr; }
  .about-features { grid-template-columns: 1fr; }
  .video-grid { grid-template-columns: 1fr; }
  .cases-grid { grid-template-columns: 1fr; }
}
@media (max-width: 480px) {
  .hero-stats { display: none; }
  .hero-btns { flex-direction: column; align-items: center; }
  .search-bar { display: none; }
}