/* ===== 秦晋联盟 品牌样式 ===== */
:root {
  --primary: #1e3a5f;
  --primary-light: #2a4f7a;
  --primary-dark: #0f2640;
  --accent: #f59e0b;
  --accent-light: #fbbf24;
  --accent-dark: #d97706;
  --bg-primary: #ffffff;
  --bg-secondary: #f8fafc;
  --bg-dark: #0b1a2e;
  --text-primary: #0f172a;
  --text-secondary: #475569;
  --text-light: #94a3b8;
  --border: #e2e8f0;
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.06);
  --shadow-md: 0 4px 16px rgba(0,0,0,0.08);
  --shadow-lg: 0 12px 40px rgba(0,0,0,0.12);
  --radius: 16px;
  --radius-sm: 8px;
  --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

* { margin: 0; padding: 0; box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  color: var(--text-primary);
  background: var(--bg-secondary);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 1.5rem;
}

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

/* ===== 导航 ===== */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 1000;
  background: rgba(255,255,255,0.8);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid rgba(226,232,240,0.5);
  transition: var(--transition);
}

.navbar.scrolled {
  box-shadow: var(--shadow-md);
  background: rgba(255,255,255,0.95);
}

.nav-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 70px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  text-decoration: none;
  color: var(--primary);
  font-weight: 800;
  font-size: 1.4rem;
}

.logo-icon {
  background: var(--primary);
  color: white;
  width: 36px;
  height: 36px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 10px;
  font-size: 1.2rem;
}

.logo-text { letter-spacing: -0.5px; }

.nav-links {
  display: flex;
  gap: 0.25rem;
}

.nav-links a {
  text-decoration: none;
  color: var(--text-secondary);
  font-weight: 500;
  padding: 0.5rem 1rem;
  border-radius: 60px;
  transition: var(--transition);
  font-size: 0.9rem;
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--primary);
  background: rgba(30,58,95,0.08);
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}

.hamburger span {
  display: block;
  width: 24px;
  height: 2.5px;
  background: var(--text-primary);
  border-radius: 4px;
  transition: 0.3s;
}

/* ===== 按钮 ===== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.65rem 1.4rem;
  border-radius: 60px;
  font-weight: 600;
  font-size: 0.9rem;
  border: none;
  cursor: pointer;
  transition: var(--transition);
  text-decoration: none;
  white-space: nowrap;
}

.btn-primary {
  background: var(--primary);
  color: white;
  box-shadow: 0 4px 12px rgba(30,58,95,0.3);
}

.btn-primary:hover {
  background: var(--primary-light);
  transform: translateY(-2px);
  box-shadow: 0 8px 20px rgba(30,58,95,0.4);
}

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

.btn-outline:hover {
  background: var(--primary);
  color: white;
}

.btn-sm { padding: 0.4rem 1rem; font-size: 0.8rem; }
.btn-lg { padding: 0.9rem 2rem; font-size: 1rem; }
.btn-block { width: 100%; justify-content: center; }

/* ===== Hero ===== */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  padding: 6rem 0 4rem;
  background: linear-gradient(135deg, #f0f4f8 0%, #e6edf5 100%);
  position: relative;
  overflow: hidden;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 3rem;
  align-items: center;
}

.hero-content .badge {
  display: inline-block;
  background: rgba(245,158,11,0.15);
  color: var(--accent-dark);
  font-weight: 600;
  font-size: 0.8rem;
  padding: 0.3rem 1rem;
  border-radius: 60px;
  margin-bottom: 1.2rem;
  letter-spacing: 0.5px;
}

.hero-content h1 {
  font-size: 3.2rem;
  font-weight: 800;
  line-height: 1.2;
  color: var(--primary-dark);
  margin-bottom: 1rem;
}

.hero-desc {
  font-size: 1.1rem;
  color: var(--text-secondary);
  margin-bottom: 2rem;
  max-width: 480px;
}

.hero-actions {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
  margin-bottom: 2.5rem;
}

.hero-stats {
  display: flex;
  gap: 2.5rem;
}

.hero-stats div {
  display: flex;
  flex-direction: column;
}

.stat-num {
  font-size: 1.8rem;
  font-weight: 800;
  color: var(--primary);
}

.stat-label {
  font-size: 0.8rem;
  color: var(--text-secondary);
  font-weight: 500;
}

.hero-visual {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  padding: 1rem 0;
}

.hero-card {
  background: var(--bg-primary);
  padding: 1.8rem 2rem;
  border-radius: var(--radius);
  box-shadow: var(--shadow-md);
  transition: var(--transition);
  position: relative;
  z-index: 2;
  width: 90%;
  margin-left: auto;
}

.hero-card.accent {
  background: var(--primary);
  color: white;
  margin-right: auto;
  margin-left: 0;
}

.hero-card i {
  font-size: 2rem;
  color: var(--accent);
  margin-bottom: 0.8rem;
}

.hero-card.accent i { color: var(--accent-light); }

.hero-card h3 { font-size: 1.2rem; margin-bottom: 0.3rem; }
.hero-card p { font-size: 0.9rem; opacity: 0.8; }

.hero-bg-shape {
  position: absolute;
  top: -20%;
  right: -10%;
  width: 280px;
  height: 280px;
  background: radial-gradient(circle, rgba(30,58,95,0.08) 0%, transparent 70%);
  border-radius: 50%;
  z-index: 1;
}

/* ===== 通用section ===== */
.section {
  padding: 5rem 0;
}

.section-alt {
  background: var(--bg-primary);
}

.section-header {
  text-align: center;
  margin-bottom: 3.5rem;
}

.section-header .badge-secondary {
  display: inline-block;
  background: rgba(30,58,95,0.08);
  color: var(--primary);
  font-weight: 600;
  font-size: 0.75rem;
  padding: 0.3rem 1rem;
  border-radius: 60px;
  margin-bottom: 0.8rem;
  letter-spacing: 0.5px;
}

.section-header h2 {
  font-size: 2.4rem;
  font-weight: 700;
  color: var(--primary-dark);
  margin-bottom: 0.5rem;
}

.section-header p {
  color: var(--text-secondary);
  max-width: 540px;
  margin: 0 auto;
}

/* ===== 卡片网格 ===== */
.cards-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 1.8rem;
}

.card {
  background: var(--bg-primary);
  padding: 2rem 1.5rem;
  border-radius: var(--radius);
  box-shadow: var(--shadow-sm);
  transition: var(--transition);
  border: 1px solid var(--border);
}

.card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-lg);
  border-color: transparent;
}

.card-icon {
  width: 56px;
  height: 56px;
  background: rgba(30,58,95,0.08);
  border-radius: 16px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.6rem;
  color: var(--primary);
  margin-bottom: 1.2rem;
}

.card h3 {
  font-size: 1.2rem;
  margin-bottom: 0.4rem;
}

.card p {
  color: var(--text-secondary);
  font-size: 0.9rem;
}

/* ===== 流程 ===== */
.process-steps {
  display: flex;
  align-items: center;
  justify-content: center;
  flex-wrap: wrap;
  gap: 0.5rem 1rem;
}

.step {
  background: var(--bg-primary);
  border-radius: var(--radius);
  padding: 1.8rem 1.5rem;
  text-align: center;
  box-shadow: var(--shadow-sm);
  flex: 1 1 160px;
  max-width: 200px;
  border: 1px solid var(--border);
  transition: var(--transition);
}

.step:hover { transform: translateY(-4px); box-shadow: var(--shadow-md); }

.step-number {
  width: 48px;
  height: 48px;
  background: var(--primary);
  color: white;
  border-radius: 60px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 1.2rem;
  margin: 0 auto 0.8rem;
}

.step h4 { font-size: 1rem; margin-bottom: 0.3rem; }
.step p { font-size: 0.8rem; color: var(--text-secondary); }

.step-arrow {
  color: var(--text-light);
  font-size: 1.4rem;
}

/* ===== 案例网格 ===== */
.cases-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 1.8rem;
}

.case-card {
  background: var(--bg-primary);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  transition: var(--transition);
  border: 1px solid var(--border);
}

.case-card:hover { transform: translateY(-6px); box-shadow: var(--shadow-lg); }

.case-img {
  height: 160px;
  background: linear-gradient(135deg, #e2e8f0, #cbd5e1);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-light);
  font-size: 2.5rem;
}

.case-img img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.case-body {
  padding: 1.5rem;
}

.case-body h3 { font-size: 1.1rem; margin-bottom: 0.2rem; }
.case-city { font-size: 0.8rem; color: var(--accent-dark); font-weight: 600; margin-bottom: 0.5rem; display: block; }
.case-body p { font-size: 0.85rem; color: var(--text-secondary); }

/* ===== FAQ ===== */
.faq-list {
  max-width: 700px;
  margin: 0 auto;
}

.faq-item {
  background: var(--bg-primary);
  border-radius: var(--radius);
  margin-bottom: 0.8rem;
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--border);
  overflow: hidden;
  transition: var(--transition);
}

.faq-question {
  padding: 1.2rem 1.5rem;
  font-weight: 600;
  display: flex;
  justify-content: space-between;
  align-items: center;
  cursor: pointer;
  user-select: none;
  transition: var(--transition);
}

.faq-question i {
  transition: transform 0.3s;
  color: var(--text-light);
}

.faq-item.active .faq-question i {
  transform: rotate(180deg);
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  padding: 0 1.5rem;
  color: var(--text-secondary);
  font-size: 0.9rem;
  transition: max-height 0.4s ease, padding 0.3s ease;
}

.faq-item.active .faq-answer {
  max-height: 200px;
  padding: 0 1.5rem 1.2rem;
}

/* ===== 联系 ===== */
.contact-wrapper {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 3rem;
  background: var(--bg-primary);
  border-radius: 28px;
  padding: 3rem;
  box-shadow: var(--shadow-md);
  border: 1px solid var(--border);
}

.contact-info h2 {
  font-size: 2rem;
  margin-bottom: 0.8rem;
}

.contact-info p {
  color: var(--text-secondary);
  margin-bottom: 2rem;
}

.contact-details {
  list-style: none;
}

.contact-details li {
  display: flex;
  align-items: center;
  gap: 1rem;
  padding: 0.7rem 0;
  font-size: 0.95rem;
  color: var(--text-primary);
}

.contact-details i {
  width: 20px;
  color: var(--accent);
  font-size: 1.1rem;
}

.contact-form {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.contact-form input,
.contact-form select,
.contact-form textarea {
  padding: 0.9rem 1.2rem;
  border: 1px solid var(--border);
  border-radius: 14px;
  font-family: inherit;
  font-size: 0.9rem;
  transition: var(--transition);
  background: var(--bg-secondary);
}

.contact-form input:focus,
.contact-form select:focus,
.contact-form textarea:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(30,58,95,0.1);
}

/* ===== 页脚 ===== */
.footer {
  background: var(--bg-dark);
  color: #cbd5e1;
  padding: 3rem 0 1.5rem;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 2rem;
}

.footer-brand .logo-text {
  color: white;
  font-size: 1.5rem;
}

.footer-brand p {
  margin: 0.5rem 0;
  font-size: 0.85rem;
  opacity: 0.7;
}

.copyright { margin-top: 1rem; font-size: 0.75rem; opacity: 0.5; }

.footer-links h5,
.footer-social h5 {
  color: white;
  margin-bottom: 1rem;
  font-size: 0.9rem;
}

.footer-links a {
  display: block;
  color: #94a3b8;
  text-decoration: none;
  font-size: 0.85rem;
  padding: 0.2rem 0;
  transition: var(--transition);
}

.footer-links a:hover { color: white; }

.social-icons {
  display: flex;
  gap: 0.8rem;
}

.social-icons a {
  color: #94a3b8;
  font-size: 1.6rem;
  transition: var(--transition);
}

.social-icons a:hover { color: var(--accent); }

/* ===== 回到顶部 ===== */
#backToTop {
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  width: 48px;
  height: 48px;
  background: var(--primary);
  color: white;
  border: none;
  border-radius: 60px;
  font-size: 1.2rem;
  cursor: pointer;
  box-shadow: var(--shadow-lg);
  transition: var(--transition);
  opacity: 0;
  visibility: hidden;
  transform: translateY(20px);
  z-index: 999;
}

#backToTop.show {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

#backToTop:hover {
  background: var(--primary-light);
  transform: translateY(-4px);
}

/* ===== 响应式 ===== */
@media (max-width: 768px) {
  .nav-links {
    position: fixed;
    top: 70px;
    left: 0;
    width: 100%;
    background: rgba(255,255,255,0.98);
    backdrop-filter: blur(16px);
    flex-direction: column;
    padding: 1rem 0;
    gap: 0;
    box-shadow: var(--shadow-md);
    transform: translateY(-120%);
    opacity: 0;
    transition: 0.35s;
    border-bottom: 1px solid var(--border);
  }

  .nav-links.open {
    transform: translateY(0);
    opacity: 1;
  }

  .nav-links a {
    padding: 0.8rem 1.5rem;
    border-radius: 0;
    width: 100%;
  }

  .hamburger { display: flex; }

  .hero-grid {
    grid-template-columns: 1fr;
    text-align: center;
  }

  .hero-content h1 { font-size: 2.4rem; }
  .hero-desc { margin-left: auto; margin-right: auto; }
  .hero-actions { justify-content: center; }
  .hero-stats { justify-content: center; gap: 1.5rem; }
  .hero-visual { align-items: center; }
  .hero-card { width: 100%; margin: 0; }

  .process-steps { flex-direction: column; }
  .step { max-width: 100%; width: 100%; }
  .step-arrow { transform: rotate(90deg); }

  .contact-wrapper {
    grid-template-columns: 1fr;
    padding: 2rem;
  }

  .footer-grid {
    grid-template-columns: 1fr 1fr;
    gap: 1.5rem;
  }

  .hide-mobile { display: none; }
}

@media (max-width: 480px) {
  .hero-content h1 { font-size: 1.8rem; }
  .section-header h2 { font-size: 1.8rem; }
  .contact-wrapper { padding: 1.5rem; }
  .footer-grid { grid-template-columns: 1fr; }
}