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

:root {
  --primary: #2A9D8F;
  --primary-dark: #1F7A6F;
  --primary-light: #E8F5F0;
  --accent: #E76F51;
  --text: #1A2B3C;
  --text-muted: #6B7C8D;
  --bg: #FAFBFC;
  --white: #FFFFFF;
  --shadow: 0 4px 24px rgba(42, 157, 143, 0.10);
  --shadow-lg: 0 8px 40px rgba(42, 157, 143, 0.15);
  --radius: 12px;
  --radius-lg: 20px;
  --transition: 0.3s ease;
  --header-h: 72px;
}

html { scroll-behavior: smooth; font-size: 16px; }

body {
  font-family: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.6;
  overflow-x: hidden;
}

img { display: block; max-width: 100%; }
a { text-decoration: none; color: inherit; }
ul { list-style: none; }

.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ===== 按钮 ===== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 14px 32px;
  border-radius: 50px;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  border: 2px solid transparent;
  transition: var(--transition);
}

.btn-primary {
  background: var(--primary);
  color: var(--white);
}
.btn-primary:hover {
  background: var(--primary-dark);
  transform: translateY(-2px);
  box-shadow: var(--shadow);
}

.btn-outline {
  background: transparent;
  color: var(--white);
  border-color: rgba(255,255,255,0.6);
}
.btn-outline:hover {
  background: rgba(255,255,255,0.15);
  border-color: var(--white);
}

/* ===== 导航栏 ===== */
.header {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 1000;
  height: var(--header-h);
  background: rgba(255,255,255,0.92);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid rgba(42,157,143,0.08);
  transition: var(--transition);
}

.header.scrolled {
  box-shadow: 0 2px 20px rgba(0,0,0,0.06);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--primary);
}

.nav {
  display: flex;
  gap: 8px;
}

.nav-link {
  padding: 8px 18px;
  border-radius: 50px;
  font-size: 0.95rem;
  color: var(--text-muted);
  transition: var(--transition);
}

.nav-link:hover,
.nav-link.active {
  color: var(--primary);
  background: var(--primary-light);
}

.menu-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
}

.menu-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--text);
  border-radius: 2px;
  transition: var(--transition);
}

.menu-toggle.active span:nth-child(1) { transform: rotate(45deg) translate(5px, 5px); }
.menu-toggle.active span:nth-child(2) { opacity: 0; }
.menu-toggle.active span:nth-child(3) { transform: rotate(-45deg) translate(5px, -5px); }

/* ===== 英雄区 ===== */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  padding-top: var(--header-h);
  overflow: hidden;
}

.hero-bg {
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, #1F7A6F 0%, #2A9D8F 40%, #3CB8A9 100%);
  z-index: 0;
}

.hero-bg::after {
  content: "";
  position: absolute;
  inset: 0;
  background:
    radial-gradient(circle at 20% 80%, rgba(255,255,255,0.08) 0%, transparent 50%),
    radial-gradient(circle at 80% 20%, rgba(255,255,255,0.06) 0%, transparent 40%);
}

.hero-content {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
  padding: 80px 24px;
}

.hero-badge {
  display: inline-block;
  padding: 6px 16px;
  background: rgba(255,255,255,0.15);
  border: 1px solid rgba(255,255,255,0.25);
  border-radius: 50px;
  color: rgba(255,255,255,0.9);
  font-size: 0.85rem;
  margin-bottom: 20px;
}

.hero-text h1 {
  font-size: clamp(2rem, 5vw, 3.2rem);
  font-weight: 800;
  color: var(--white);
  line-height: 1.25;
  margin-bottom: 20px;
}

.hero-text p {
  font-size: 1.1rem;
  color: rgba(255,255,255,0.85);
  max-width: 480px;
  margin-bottom: 32px;
}

.hero-actions {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
  margin-bottom: 32px;
}

.hero-tags {
  display: flex;
  gap: 20px;
  flex-wrap: wrap;
}

.hero-tags span {
  color: rgba(255,255,255,0.75);
  font-size: 0.9rem;
}

.hero-card {
  background: rgba(255,255,255,0.12);
  backdrop-filter: blur(20px);
  border: 1px solid rgba(255,255,255,0.2);
  border-radius: var(--radius-lg);
  padding: 32px;
  color: var(--white);
}

.hero-card-header {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 24px;
  font-weight: 600;
}

.hero-card-header svg {
  width: 22px;
  height: 22px;
}

.hero-stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
  margin-bottom: 28px;
}

.hero-stat {
  text-align: center;
  padding: 16px 8px;
  background: rgba(255,255,255,0.08);
  border-radius: var(--radius);
}

.hero-stat strong {
  display: block;
  font-size: 1.6rem;
  font-weight: 800;
}

.hero-stat small {
  font-size: 0.8rem;
  opacity: 0.7;
}

.hero-chart {
  display: flex;
  align-items: flex-end;
  gap: 8px;
  height: 80px;
}

.hero-chart .bar {
  flex: 1;
  background: rgba(255,255,255,0.3);
  border-radius: 4px 4px 0 0;
  transition: height 1s ease;
}

/* ===== 通用区块 ===== */
.section {
  padding: 100px 0;
}

.section-header {
  text-align: center;
  max-width: 600px;
  margin: 0 auto 60px;
}

.section-tag {
  display: inline-block;
  padding: 4px 14px;
  background: var(--primary-light);
  color: var(--primary);
  border-radius: 50px;
  font-size: 0.85rem;
  font-weight: 600;
  margin-bottom: 16px;
}

.section-header h2 {
  font-size: clamp(1.6rem, 3vw, 2.2rem);
  font-weight: 800;
  margin-bottom: 12px;
}

.section-header p {
  color: var(--text-muted);
  font-size: 1.05rem;
}

/* ===== 功能卡片 ===== */
.features { background: var(--white); }

.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
}

.feature-card {
  padding: 36px 28px;
  background: var(--bg);
  border-radius: var(--radius-lg);
  transition: var(--transition);
  border: 1px solid transparent;
}

.feature-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-lg);
  border-color: rgba(42,157,143,0.15);
  background: var(--white);
}

.feature-icon {
  width: 64px;
  height: 64px;
  border-radius: 16px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
}

.feature-icon svg { width: 36px; height: 36px; }

.feature-card h3 {
  font-size: 1.15rem;
  font-weight: 700;
  margin-bottom: 10px;
}

.feature-card p {
  color: var(--text-muted);
  font-size: 0.95rem;
  line-height: 1.7;
}

/* ===== 流程步骤 ===== */
.process { background: var(--bg); }

.process-steps {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  position: relative;
}

.process-steps::before {
  content: "";
  position: absolute;
  top: 36px;
  left: 12.5%;
  right: 12.5%;
  height: 2px;
  background: linear-gradient(90deg, var(--primary), var(--primary-light), var(--primary));
  z-index: 0;
}

.step {
  text-align: center;
  position: relative;
  z-index: 1;
}

.step-num {
  width: 72px;
  height: 72px;
  margin: 0 auto 20px;
  background: var(--primary);
  color: var(--white);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.3rem;
  font-weight: 800;
  box-shadow: 0 4px 16px rgba(42,157,143,0.3);
}

.step-body h3 {
  font-size: 1.05rem;
  font-weight: 700;
  margin-bottom: 8px;
}

.step-body p {
  color: var(--text-muted);
  font-size: 0.9rem;
  line-height: 1.6;
  padding: 0 8px;
}

/* ===== 数据统计 ===== */
.stats {
  background: linear-gradient(135deg, var(--primary-dark), var(--primary));
  padding: 80px 0;
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 32px;
  text-align: center;
}

.stat-item strong {
  display: block;
  font-size: clamp(2rem, 4vw, 3rem);
  font-weight: 800;
  color: var(--white);
  margin-bottom: 8px;
}

.stat-item strong::after {
  content: "+";
  font-size: 0.6em;
  vertical-align: super;
}

.stat-item span {
  color: rgba(255,255,255,0.8);
  font-size: 1rem;
}

/* ===== 关于 ===== */
.about { background: var(--white); }

.about-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
}

.about-text h2 {
  font-size: clamp(1.6rem, 3vw, 2rem);
  font-weight: 800;
  margin-bottom: 16px;
}

.about-text p {
  color: var(--text-muted);
  margin-bottom: 24px;
  line-height: 1.8;
}

.about-list li {
  padding: 10px 0;
  padding-left: 28px;
  position: relative;
  color: var(--text);
  font-size: 0.95rem;
}

.about-list li::before {
  content: "✓";
  position: absolute;
  left: 0;
  color: var(--primary);
  font-weight: 700;
}

/* ===== 联系 ===== */
.contact { background: var(--bg); }

.contact-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
}

.contact-card {
  background: var(--white);
  padding: 40px 28px;
  border-radius: var(--radius-lg);
  text-align: center;
  box-shadow: var(--shadow);
  transition: var(--transition);
}

.contact-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}

.contact-icon {
  font-size: 2.4rem;
  margin-bottom: 16px;
}

.contact-card h3 {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 12px;
}

.contact-card p {
  color: var(--text-muted);
  font-size: 0.95rem;
  line-height: 1.8;
}

/* ===== 页脚 ===== */
.footer {
  background: #142830;
  color: rgba(255,255,255,0.7);
  padding: 40px 0;
}

.footer-inner {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 16px;
  text-align: center;
}

.footer-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  color: var(--white);
  font-weight: 600;
}

.footer-copy {
  font-size: 0.85rem;
}

/* ===== 响应式 - 平板 ===== */
@media (max-width: 992px) {
  .hero-content {
    grid-template-columns: 1fr;
    text-align: center;
    gap: 40px;
    padding: 60px 24px;
  }

  .hero-text p { margin-left: auto; margin-right: auto; }
  .hero-actions { justify-content: center; }
  .hero-tags { justify-content: center; }

  .features-grid { grid-template-columns: repeat(2, 1fr); }

  .process-steps {
    grid-template-columns: repeat(2, 1fr);
    gap: 40px;
  }
  .process-steps::before { display: none; }

  .stats-grid { grid-template-columns: repeat(2, 1fr); }

  .about-grid { grid-template-columns: 1fr; }

  .contact-grid { grid-template-columns: 1fr; max-width: 400px; margin: 0 auto; }
}

/* ===== 响应式 - 手机 ===== */
@media (max-width: 768px) {
  :root { --header-h: 64px; }

  .nav {
    position: fixed;
    top: var(--header-h);
    left: 0; right: 0;
    background: var(--white);
    flex-direction: column;
    padding: 16px 24px;
    gap: 4px;
    box-shadow: 0 8px 24px rgba(0,0,0,0.08);
    transform: translateY(-120%);
    opacity: 0;
    transition: var(--transition);
    pointer-events: none;
  }

  .nav.open {
    transform: translateY(0);
    opacity: 1;
    pointer-events: auto;
  }

  .nav-link {
    padding: 12px 16px;
    font-size: 1rem;
  }

  .menu-toggle { display: flex; }

  .hero-content { padding: 40px 24px; }

  .hero-stats { grid-template-columns: repeat(3, 1fr); gap: 8px; }
  .hero-stat { padding: 12px 4px; }
  .hero-stat strong { font-size: 1.2rem; }

  .features-grid { grid-template-columns: 1fr; }

  .process-steps { grid-template-columns: 1fr; }

  .stats-grid { grid-template-columns: repeat(2, 1fr); gap: 24px; }

  .section { padding: 64px 0; }

  .hero-actions .btn { width: 100%; }
}

@media (max-width: 480px) {
  .hero-tags { flex-direction: column; gap: 8px; align-items: center; }
  .hero-card { padding: 24px 16px; }
}