/* ===== 全局重置 & 变量 ===== */
*,
*::before,
*::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --primary: #e94560;
  --primary-light: #ff6b6b;
  --secondary: #16213e;
  --accent: #0f3460;
  --glass: rgba(255, 255, 255, 0.08);
  --text: #e0e0e0;
  --bg: #0a0a1a;
  --card-bg: rgba(255, 255, 255, 0.04);
  --shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
  --radius: 16px;
  --transition: 0.3s ease;
  --font-family: system-ui, -apple-system, 'Segoe UI', Roboto, sans-serif;
}

body.dark {
  --bg: #0a0a1a;
  --text: #e0e0e0;
  --card-bg: rgba(255, 255, 255, 0.04);
  --glass: rgba(255, 255, 255, 0.08);
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-family);
  background: var(--bg);
  color: var(--text);
  line-height: 1.7;
  overflow-x: hidden;
  transition: background var(--transition), color var(--transition);
}

a {
  color: var(--primary);
  text-decoration: none;
  transition: var(--transition);
}
a:hover {
  opacity: 0.8;
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

ul {
  list-style: none;
}

.container {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 24px;
}

h1, h2, h3, h4 {
  font-weight: 700;
  line-height: 1.3;
}

h1 {
  font-size: clamp(2rem, 5vw, 3.2rem);
  background: linear-gradient(135deg, var(--primary), var(--primary-light));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

h2 {
  font-size: clamp(1.6rem, 4vw, 2.4rem);
  margin-bottom: 24px;
  position: relative;
  display: inline-block;
}
h2::after {
  content: '';
  position: absolute;
  bottom: -8px;
  left: 0;
  width: 60px;
  height: 4px;
  background: var(--primary);
  border-radius: 2px;
}

h3 {
  font-size: clamp(1.2rem, 3vw, 1.6rem);
  margin-bottom: 12px;
}

/* ===== 通用类 ===== */
.section {
  padding: 80px 0;
}

.glass {
  background: var(--glass);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid rgba(255, 255, 255, 0.06);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

.card {
  background: var(--card-bg);
  border-radius: var(--radius);
  padding: 32px;
  transition: transform var(--transition), box-shadow var(--transition);
  border: 1px solid rgba(255, 255, 255, 0.04);
}
.card:hover {
  transform: translateY(-6px);
  box-shadow: 0 12px 40px rgba(233, 69, 96, 0.15);
}

.grid {
  display: grid;
  gap: 32px;
}
.grid-2 {
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
}
.grid-3 {
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
}
.grid-4 {
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
}

.btn {
  display: inline-block;
  padding: 12px 32px;
  background: linear-gradient(135deg, var(--primary), var(--primary-light));
  color: #fff;
  border-radius: 50px;
  font-weight: 600;
  border: none;
  cursor: pointer;
  transition: var(--transition);
  text-align: center;
  text-decoration: none;
}
.btn:hover {
  transform: scale(1.04);
  box-shadow: 0 8px 24px rgba(233, 69, 96, 0.3);
}

.btn-outline {
  background: transparent;
  border: 2px solid var(--primary);
  color: var(--primary);
}
.btn-outline:hover {
  background: var(--primary);
  color: #fff;
}

.badge {
  display: inline-block;
  padding: 4px 16px;
  background: rgba(233, 69, 96, 0.15);
  border-radius: 50px;
  font-size: 0.85rem;
  color: var(--primary);
  margin-bottom: 12px;
}

.text-center {
  text-align: center;
}

.mb-16 {
  margin-bottom: 16px;
}
.mb-32 {
  margin-bottom: 32px;
}
.mt-32 {
  margin-top: 32px;
}

/* ===== 滚动动画 ===== */
.fade-in {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.8s ease, transform 0.8s ease;
}
.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ===== Banner ===== */
.banner {
  position: relative;
  min-height: 85vh;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  background: linear-gradient(135deg, #0a0a1a 0%, #1a1a2e 50%, #16213e 100%);
}
.banner::before {
  content: '';
  position: absolute;
  inset: 0;
  background: radial-gradient(circle at 20% 50%, rgba(233, 69, 96, 0.12) 0%, transparent 60%),
              radial-gradient(circle at 80% 30%, rgba(15, 52, 96, 0.2) 0%, transparent 50%);
  z-index: 1;
  pointer-events: none;
}
.banner-content {
  position: relative;
  z-index: 2;
  text-align: center;
  max-width: 800px;
  padding: 40px 24px;
}
.banner h1 {
  margin-bottom: 24px;
}
.banner p {
  font-size: clamp(1rem, 2vw, 1.2rem);
  margin-bottom: 32px;
  opacity: 0.85;
}
.banner-btns {
  display: flex;
  gap: 16px;
  justify-content: center;
  flex-wrap: wrap;
}

/* ===== 统计 ===== */
.stat-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
  gap: 24px;
  margin-top: 40px;
}
.stat-item {
  text-align: center;
  padding: 24px;
  background: var(--card-bg);
  border-radius: var(--radius);
}
.stat-number {
  font-size: 2.8rem;
  font-weight: 800;
  background: linear-gradient(135deg, var(--primary), var(--primary-light));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}
.stat-label {
  font-size: 0.95rem;
  opacity: 0.7;
  margin-top: 8px;
}

/* ===== 轮播 ===== */
.carousel {
  position: relative;
  overflow: hidden;
  border-radius: var(--radius);
}
.carousel-track {
  display: flex;
  transition: transform 0.6s ease;
}
.carousel-slide {
  min-width: 100%;
  padding: 40px;
  background: var(--card-bg);
  border-radius: var(--radius);
  text-align: center;
}
.carousel-btn {
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  background: var(--glass);
  border: none;
  color: #fff;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  cursor: pointer;
  font-size: 1.4rem;
  backdrop-filter: blur(8px);
  z-index: 5;
  transition: var(--transition);
}
.carousel-btn:hover {
  background: var(--primary);
}
.carousel-btn.prev {
  left: 12px;
}
.carousel-btn.next {
  right: 12px;
}
.carousel-dots {
  display: flex;
  justify-content: center;
  gap: 10px;
  margin-top: 20px;
}
.carousel-dots span {
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.2);
  cursor: pointer;
  transition: var(--transition);
}
.carousel-dots span.active {
  background: var(--primary);
  width: 32px;
  border-radius: 6px;
}

/* ===== 手风琴 / FAQ ===== */
.accordion-item {
  border-bottom: 1px solid rgba(255, 255, 255, 0.06);
  padding: 16px 0;
}
.accordion-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  cursor: pointer;
  font-weight: 600;
  font-size: 1.1rem;
  padding: 8px 0;
}
.accordion-header .icon {
  transition: transform 0.3s ease;
  font-size: 1.2rem;
}
.accordion-item.active .accordion-header .icon {
  transform: rotate(45deg);
}
.accordion-body {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.4s ease;
  padding: 0 16px;
}
.accordion-item.active .accordion-body {
  max-height: 600px;
  padding: 16px 16px 24px;
}

.faq-item {
  margin-bottom: 16px;
}
.faq-question {
  font-weight: 600;
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 16px;
  background: var(--card-bg);
  border-radius: 12px;
  transition: var(--transition);
}
.faq-question:hover {
  background: rgba(233, 69, 96, 0.08);
}
.faq-answer {
  padding: 16px 16px 24px;
  line-height: 1.8;
  display: none;
}
.faq-item.active .faq-answer {
  display: block;
}

/* ===== How-to 步骤 ===== */
.howto-step {
  display: flex;
  gap: 20px;
  margin-bottom: 24px;
  align-items: flex-start;
}
.howto-step-num {
  min-width: 48px;
  height: 48px;
  border-radius: 50%;
  background: var(--primary);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 800;
  font-size: 1.2rem;
  color: #fff;
  flex-shrink: 0;
}

/* ===== Footer ===== */
footer {
  background: var(--secondary);
  padding: 60px 0 20px;
  margin-top: 80px;
}
.footer-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 40px;
  margin-bottom: 40px;
}
.footer-col h4 {
  color: var(--primary);
  margin-bottom: 16px;
  font-size: 1.1rem;
}
.footer-col ul {
  list-style: none;
}
.footer-col ul li {
  margin-bottom: 8px;
}
.footer-col ul li a {
  opacity: 0.7;
  font-size: 0.95rem;
  color: var(--text);
}
.footer-col ul li a:hover {
  opacity: 1;
}
.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.06);
  padding-top: 24px;
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  align-items: center;
  font-size: 0.9rem;
  opacity: 0.6;
}

/* ===== QR 占位 ===== */
.qr-placeholder {
  width: 120px;
  height: 120px;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.8rem;
  text-align: center;
  margin-top: 12px;
  color: #fff;
  opacity: 0.8;
}

/* ===== 返回顶部 ===== */
.back-to-top {
  position: fixed;
  bottom: 40px;
  right: 40px;
  width: 52px;
  height: 52px;
  border-radius: 50%;
  background: var(--primary);
  color: #fff;
  border: none;
  cursor: pointer;
  font-size: 1.5rem;
  box-shadow: 0 8px 24px rgba(233, 69, 96, 0.3);
  z-index: 100;
  opacity: 0;
  visibility: hidden;
  transition: var(--transition);
  display: flex;
  align-items: center;
  justify-content: center;
}
.back-to-top.show {
  opacity: 1;
  visibility: visible;
}
.back-to-top:hover {
  transform: scale(1.1);
}

/* ===== Header ===== */
header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  background: rgba(10, 10, 26, 0.85);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid rgba(255, 255, 255, 0.04);
}
.header-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 16px 24px;
  max-width: 1280px;
  margin: 0 auto;
}
.logo {
  font-size: 1.6rem;
  font-weight: 800;
  background: linear-gradient(135deg, var(--primary), var(--primary-light));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  white-space: nowrap;
}
nav {
  display: flex;
  align-items: center;
  gap: 32px;
}
.nav-links {
  display: flex;
  gap: 24px;
  list-style: none;
}
.nav-links a {
  color: var(--text);
  font-weight: 500;
  font-size: 0.95rem;
  position: relative;
  padding: 4px 0;
}
.nav-links a::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--primary);
  transition: width 0.3s ease;
}
.nav-links a:hover::after,
.nav-links a.active::after {
  width: 100%;
}

.dark-toggle {
  background: var(--glass);
  border: 1px solid rgba(255, 255, 255, 0.1);
  color: var(--text);
  width: 40px;
  height: 40px;
  border-radius: 50%;
  cursor: pointer;
  font-size: 1.2rem;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: var(--transition);
}
.dark-toggle:hover {
  background: var(--primary);
}

.mobile-menu-btn {
  display: none;
  background: none;
  border: none;
  color: var(--text);
  font-size: 1.8rem;
  cursor: pointer;
  padding: 8px;
}

/* ===== 搜索框 ===== */
.search-box {
  display: flex;
  align-items: center;
  background: var(--glass);
  border-radius: 50px;
  padding: 4px 16px;
  border: 1px solid rgba(255, 255, 255, 0.06);
}
.search-box input {
  background: none;
  border: none;
  color: var(--text);
  padding: 8px;
  outline: none;
  width: 140px;
  font-size: 0.9rem;
}
.search-box input::placeholder {
  color: rgba(255, 255, 255, 0.4);
}
.search-box button {
  background: none;
  border: none;
  color: var(--text);
  cursor: pointer;
  font-size: 1.1rem;
}

/* ===== 图片占位 ===== */
img[loading="lazy"] {
  background: linear-gradient(135deg, #1a1a2e, #16213e);
  border-radius: 8px;
  min-height: 100px;
}

/* ===== 响应式 ===== */
@media (max-width: 768px) {
  .mobile-menu-btn {
    display: block;
  }
  .nav-links {
    display: none;
    position: absolute;
    top: 70px;
    left: 0;
    right: 0;
    background: var(--bg);
    flex-direction: column;
    padding: 24px;
    gap: 16px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.06);
  }
  .nav-links.open {
    display: flex;
  }
  .section {
    padding: 48px 0;
  }
  .banner {
    min-height: 60vh;
  }
  .carousel-btn {
    width: 36px;
    height: 36px;
    font-size: 1rem;
  }
  .stat-number {
    font-size: 2rem;
  }
  .footer-grid {
    grid-template-columns: 1fr 1fr;
  }
  .search-box input {
    width: 100px;
  }
}

@media (max-width: 480px) {
  .container {
    padding: 0 16px;
  }
  .grid-2,
  .grid-3,
  .grid-4 {
    grid-template-columns: 1fr;
  }
  .footer-grid {
    grid-template-columns: 1fr;
  }
  .header-inner {
    padding: 12px 16px;
  }
  .logo {
    font-size: 1.3rem;
  }
}

/* ===== 暗色模式额外适配 ===== */
body.dark .search-box input {
  color: var(--text);
}

/* ===== 可访问性 ===== */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}