/* ============================================
   0009 - Shared Styles
   Design: SaaS Style, Primary: indigo-600
   ============================================ */

/* --- Custom Properties (overrides/extensions) --- */
:root {
  --primary: #4F46E5;
  --primary-dark: #4338CA;
  --primary-light: #818CF8;
  --primary-bg: #EEF2FF;
  --accent: #F59E0B;
  --dark: #1E293B;
  --gray: #64748B;
  --light: #F8FAFC;
}

/* --- Smooth Scroll --- */
html {
  scroll-behavior: smooth;
}

/* --- Navbar Scroll Effect --- */
.navbar-scrolled {
  background: rgba(255, 255, 255, 0.98) !important;
  box-shadow: 0 4px 24px rgba(0, 0, 0, 0.08);
  backdrop-filter: blur(12px);
}

/* --- Mobile Menu --- */
.mobile-menu {
  transition: max-height 0.4s cubic-bezier(0.4, 0, 0.2, 1), opacity 0.3s ease;
  max-height: 0;
  opacity: 0;
  overflow: hidden;
}
.mobile-menu.open {
  max-height: 400px;
  opacity: 1;
}

/* --- Hero Section --- */
.hero-gradient {
  background: linear-gradient(135deg, #EEF2FF 0%, #E0E7FF 40%, #C7D2FE 100%);
}
.hero-btn-primary {
  transition: all 0.3s ease;
  box-shadow: 0 4px 16px rgba(79, 70, 229, 0.35);
}
.hero-btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 28px rgba(79, 70, 229, 0.45);
}
.hero-btn-secondary {
  transition: all 0.3s ease;
}
.hero-btn-secondary:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.08);
}

/* --- Feature Cards --- */
.feature-card {
  transition: all 0.35s cubic-bezier(0.4, 0, 0.2, 1);
  border: 1px solid rgba(226, 232, 240, 0.6);
}
.feature-card:hover {
  transform: translateY(-8px);
  box-shadow: 0 20px 40px rgba(79, 70, 229, 0.12);
  border-color: rgba(79, 70, 229, 0.25);
}
.feature-icon-wrapper {
  width: 56px;
  height: 56px;
  border-radius: 14px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 24px;
  transition: all 0.3s ease;
}
.feature-card:hover .feature-icon-wrapper {
  transform: scale(1.08);
}

/* --- Stats Counter --- */
.stat-number {
  background: linear-gradient(135deg, #4F46E5 0%, #6366F1 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* --- FAQ Accordion --- */
.faq-item {
  border: 1px solid #E2E8F0;
  border-radius: 12px;
  overflow: hidden;
  transition: all 0.3s ease;
  margin-bottom: 12px;
}
.faq-item:hover {
  border-color: #C7D2FE;
}
.faq-question {
  cursor: pointer;
  padding: 18px 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-weight: 600;
  color: #1E293B;
  background: #fff;
  transition: all 0.25s ease;
  user-select: none;
}
.faq-question:hover {
  background: #F8FAFC;
}
.faq-question .faq-icon {
  transition: transform 0.35s cubic-bezier(0.4, 0, 0.2, 1);
  font-size: 14px;
  color: #4F46E5;
  flex-shrink: 0;
  margin-left: 16px;
}
.faq-item.active .faq-question .faq-icon {
  transform: rotate(180deg);
}
.faq-item.active .faq-question {
  color: #4F46E5;
  background: #EEF2FF;
}
.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}
.faq-item.active .faq-answer {
  max-height: 300px;
}
.faq-answer-inner {
  padding: 0 24px 20px 24px;
  color: #475569;
  line-height: 1.7;
}

/* --- CTA Section --- */
.cta-section {
  background: linear-gradient(135deg, #4F46E5 0%, #4338CA 100%);
  position: relative;
  overflow: hidden;
}
.cta-section::before {
  content: '';
  position: absolute;
  top: -50%;
  right: -20%;
  width: 500px;
  height: 500px;
  background: radial-gradient(circle, rgba(255,255,255,0.08) 0%, transparent 70%);
  border-radius: 50%;
  pointer-events: none;
}
.cta-section::after {
  content: '';
  position: absolute;
  bottom: -30%;
  left: -10%;
  width: 350px;
  height: 350px;
  background: radial-gradient(circle, rgba(255,255,255,0.06) 0%, transparent 70%);
  border-radius: 50%;
  pointer-events: none;
}
.cta-btn {
  transition: all 0.3s ease;
}
.cta-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 28px rgba(0, 0, 0, 0.2);
}

/* --- Platform Download Cards --- */
.download-card {
  transition: all 0.35s cubic-bezier(0.4, 0, 0.2, 1);
  border: 1px solid rgba(226, 232, 240, 0.6);
}
.download-card:hover {
  transform: translateY(-6px);
  box-shadow: 0 20px 40px rgba(79, 70, 229, 0.15);
}
.download-card.featured {
  border: 2px solid #4F46E5;
  position: relative;
}
.download-card.featured::after {
  content: '推荐';
  position: absolute;
  top: 12px;
  right: 12px;
  background: linear-gradient(135deg, #4F46E5, #6366F1);
  color: #fff;
  font-size: 12px;
  padding: 4px 12px;
  border-radius: 20px;
  font-weight: 600;
}

/* --- Club Cards --- */
.club-card {
  transition: all 0.35s cubic-bezier(0.4, 0, 0.2, 1);
  border: 1px solid rgba(226, 232, 240, 0.6);
}
.club-card:hover {
  transform: translateY(-6px);
  box-shadow: 0 20px 40px rgba(79, 70, 229, 0.12);
  border-color: rgba(79, 70, 229, 0.25);
}
.club-stars {
  color: #F59E0B;
  letter-spacing: 2px;
  font-size: 18px;
}
.club-badge {
  display: inline-block;
  padding: 4px 10px;
  border-radius: 6px;
  font-size: 12px;
  font-weight: 600;
}

/* --- Step Timeline --- */
.step-number {
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: linear-gradient(135deg, #4F46E5, #6366F1);
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 20px;
  flex-shrink: 0;
  box-shadow: 0 4px 16px rgba(79, 70, 229, 0.3);
}
.step-line {
  width: 2px;
  background: linear-gradient(to bottom, #4F46E5, #C7D2FE);
  flex-grow: 1;
  min-height: 40px;
}

/* --- Rating Stars (interactive feel) --- */
.star-rating .star {
  transition: transform 0.2s ease;
  display: inline-block;
}
.star-rating .star:hover {
  transform: scale(1.2);
}

/* --- Footer --- */
.footer-link {
  transition: color 0.25s ease;
}
.footer-link:hover {
  color: #4F46E5;
}

/* --- Back to Top Button --- */
.back-to-top {
  position: fixed;
  bottom: 32px;
  right: 32px;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: #4F46E5;
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  opacity: 0;
  transform: translateY(20px);
  pointer-events: none;
  transition: all 0.3s ease;
  box-shadow: 0 4px 16px rgba(79, 70, 229, 0.35);
  z-index: 50;
  border: none;
  font-size: 18px;
}
.back-to-top.visible {
  opacity: 1;
  transform: translateY(0);
  pointer-events: auto;
}
.back-to-top:hover {
  transform: translateY(-4px);
  box-shadow: 0 8px 24px rgba(79, 70, 229, 0.45);
}

/* --- Pulse Animation for CTA --- */
@keyframes pulse-ring {
  0% {
    box-shadow: 0 0 0 0 rgba(79, 70, 229, 0.5);
  }
  70% {
    box-shadow: 0 0 0 18px rgba(79, 70, 229, 0);
  }
  100% {
    box-shadow: 0 0 0 0 rgba(79, 70, 229, 0);
  }
}
.pulse-animate {
  animation: pulse-ring 2.5s infinite;
}

/* --- Fade In Up Animation --- */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}
.animate-fade-in-up {
  animation: fadeInUp 0.6s ease forwards;
}
.animate-delay-100 { animation-delay: 0.1s; }
.animate-delay-200 { animation-delay: 0.2s; }
.animate-delay-300 { animation-delay: 0.3s; }
.animate-delay-400 { animation-delay: 0.4s; }
.animate-delay-500 { animation-delay: 0.5s; }

/* --- Page Header --- */
.page-header {
  background: linear-gradient(135deg, #EEF2FF 0%, #E0E7FF 40%, #C7D2FE 100%);
  padding: 80px 0 60px;
}

/* --- Breadcrumb / Back Link --- */
.back-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  color: #4F46E5;
  font-weight: 500;
  transition: all 0.25s ease;
  text-decoration: none;
}
.back-link:hover {
  gap: 10px;
  color: #4338CA;
}

/* --- Install Steps Image Placeholder --- */
.step-image {
  width: 100%;
  height: 180px;
  background: linear-gradient(135deg, #F1F5F9 0%, #E2E8F0 100%);
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 48px;
  color: #94A3B8;
  border: 2px dashed #CBD5E1;
}

/* --- Responsive Fine-tuning --- */
@media (max-width: 768px) {
  .hero-gradient {
    padding: 60px 0 40px;
  }
  .page-header {
    padding: 60px 0 40px;
  }
  .feature-card:hover {
    transform: translateY(-4px);
  }
  .download-card:hover,
  .club-card:hover {
    transform: translateY(-4px);
  }
  .back-to-top {
    bottom: 20px;
    right: 20px;
  }
}