/* 闪跃 (FlashLeap) 官方极速落地页样式表 - 清爽浅色主题 (Light Theme) */
:root {
  --bg-light: #f8fafc;
  --bg-card: #ffffff;
  --bg-card-hover: #f1f5f9;
  --border-color: #e2e8f0;
  --border-highlight: #2563eb;
  --text-main: #0f172a;
  --text-muted: #475569;
  --primary-cyan: #0284c7;
  --primary-blue: #2563eb;
  --accent-purple: #7c3aed;
  --accent-pink: #db2777;
  --gradient-primary: linear-gradient(135deg, #0284c7 0%, #2563eb 100%);
  --gradient-accent: linear-gradient(135deg, #7c3aed 0%, #4f46e5 100%);
  --gradient-card: linear-gradient(180deg, #ffffff 0%, #f8fafc 100%);
  --shadow-glow: 0 8px 25px rgba(37, 99, 235, 0.2);
  --shadow-card: 0 4px 20px -2px rgba(15, 23, 42, 0.06), 0 2px 6px -1px rgba(15, 23, 42, 0.04);
  --shadow-hover: 0 12px 30px -4px rgba(37, 99, 235, 0.12), 0 4px 12px -2px rgba(15, 23, 42, 0.08);
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --font-stack: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
}

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

html {
  scroll-behavior: smooth;
  font-family: var(--font-stack);
  background-color: var(--bg-light);
  color: var(--text-main);
  line-height: 1.6;
}

body {
  overflow-x: hidden;
  background: radial-gradient(circle at 50% -10%, #e0f2fe 0%, var(--bg-light) 65%);
  min-height: 100vh;
}

/* 通用容器与类 */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

.text-gradient {
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.text-purple {
  background: var(--gradient-accent);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

/* 按钮通用规范 */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 14px 28px;
  font-size: 1rem;
  font-weight: 700;
  border-radius: 50px;
  text-decoration: none;
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  cursor: pointer;
  white-space: nowrap;
  min-height: 48px;
}

.btn-primary {
  background: var(--gradient-primary);
  color: #ffffff;
  box-shadow: var(--shadow-glow);
}

.btn-primary:hover {
  transform: translateY(-2px) scale(1.02);
  box-shadow: 0 10px 30px rgba(37, 99, 235, 0.35);
  color: #ffffff;
}

.btn-outline {
  background: #ffffff;
  color: var(--text-main);
  border: 1.5px solid var(--border-color);
  box-shadow: 0 2px 5px rgba(0, 0, 0, 0.03);
}

.btn-outline:hover {
  border-color: var(--primary-cyan);
  color: var(--primary-cyan);
  background: rgba(2, 132, 199, 0.04);
}

.btn-lg {
  padding: 18px 36px;
  font-size: 1.125rem;
}

/* 顶部导航 */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: rgba(255, 255, 255, 0.88);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid rgba(226, 232, 240, 0.8);
  height: 72px;
  display: flex;
  align-items: center;
}

.navbar .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
}

.brand-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  font-size: 1.5rem;
  font-weight: 900;
  color: var(--text-main);
  letter-spacing: -0.5px;
}

.brand-logo svg {
  width: 32px;
  height: 32px;
  color: var(--primary-cyan);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 32px;
  list-style: none;
}

.nav-links a {
  color: var(--text-muted);
  text-decoration: none;
  font-size: 0.95rem;
  font-weight: 600;
  transition: color 0.2s ease;
}

.nav-links a:hover {
  color: var(--primary-cyan);
}

/* 主视觉 Hero 区域 */
.hero-section {
  padding: 160px 0 90px;
  text-align: center;
  position: relative;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 18px;
  border-radius: 30px;
  background: rgba(2, 132, 199, 0.08);
  border: 1px solid rgba(2, 132, 199, 0.2);
  color: var(--primary-cyan);
  font-size: 0.875rem;
  font-weight: 700;
  margin-bottom: 24px;
}

.hero-title {
  font-size: 3.5rem;
  font-weight: 900;
  line-height: 1.15;
  letter-spacing: -1px;
  color: var(--text-main);
  margin-bottom: 24px;
  max-width: 900px;
  margin-left: auto;
  margin-right: auto;
}

.hero-subtitle {
  font-size: 1.25rem;
  color: var(--text-muted);
  max-width: 720px;
  margin: 0 auto 40px;
  font-weight: 400;
}

.hero-cta {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  margin-bottom: 60px;
}

.hero-stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  max-width: 960px;
  margin: 0 auto;
  padding: 32px;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-card);
}

.stat-item h3 {
  font-size: 2rem;
  font-weight: 800;
  color: var(--primary-cyan);
}

.stat-item p {
  font-size: 0.875rem;
  color: var(--text-muted);
  margin-top: 4px;
  font-weight: 500;
}

/* 核心优势板块 */
.section-padding {
  padding: 100px 0;
}

.section-header {
  text-align: center;
  margin-bottom: 60px;
}

.section-tag {
  font-size: 0.875rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 1.5px;
  color: var(--primary-cyan);
  margin-bottom: 12px;
  display: block;
}

.section-title {
  font-size: 2.5rem;
  font-weight: 900;
  letter-spacing: -0.5px;
  color: var(--text-main);
}

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

.advantage-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  padding: 32px 24px;
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-card);
  transition: all 0.3s ease;
}

.advantage-card:hover {
  transform: translateY(-5px);
  border-color: var(--border-highlight);
  box-shadow: var(--shadow-hover);
}

.card-icon {
  width: 54px;
  height: 54px;
  border-radius: 12px;
  background: rgba(2, 132, 199, 0.1);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--primary-cyan);
  margin-bottom: 20px;
}

.advantage-card h3 {
  font-size: 1.25rem;
  font-weight: 800;
  margin-bottom: 12px;
  color: var(--text-main);
}

.advantage-card p {
  color: var(--text-muted);
  font-size: 0.95rem;
}

/* 流媒体与 AI 支持 */
.support-section {
  background: linear-gradient(180deg, var(--bg-light) 0%, #f1f5f9 50%, var(--bg-light) 100%);
}

.support-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 32px;
}

.support-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  padding: 40px;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-card);
  position: relative;
  overflow: hidden;
}

.support-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 4px;
  background: var(--gradient-primary);
}

.support-card.ai::before {
  background: var(--gradient-accent);
}

.support-card h3 {
  font-size: 1.75rem;
  font-weight: 800;
  margin-bottom: 16px;
  display: flex;
  align-items: center;
  gap: 12px;
  color: var(--text-main);
}

.support-card h3 svg {
  color: var(--primary-cyan);
}

.support-card.ai h3 svg {
  color: var(--accent-purple);
}

.support-card p {
  color: var(--text-muted);
  margin-bottom: 24px;
  font-size: 1rem;
}

.tag-cloud {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.tech-tag {
  padding: 8px 16px;
  background: #f1f5f9;
  border: 1px solid var(--border-color);
  border-radius: 30px;
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--text-main);
  display: flex;
  align-items: center;
  gap: 6px;
}

/* 套餐价格对比 */
.pricing-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 32px;
  align-items: stretch;
}

.pricing-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 40px 32px;
  display: flex;
  flex-direction: column;
  position: relative;
  box-shadow: var(--shadow-card);
  transition: all 0.3s ease;
}

.pricing-card.popular {
  border-color: var(--primary-blue);
  background: linear-gradient(180deg, #ffffff 0%, #eff6ff 100%);
  transform: scale(1.04);
  box-shadow: var(--shadow-glow);
}

.badge-popular {
  position: absolute;
  top: -16px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--gradient-primary);
  color: #ffffff;
  font-size: 0.8125rem;
  font-weight: 800;
  padding: 6px 18px;
  border-radius: 20px;
  letter-spacing: 0.5px;
  box-shadow: 0 4px 12px rgba(37, 99, 235, 0.25);
}

.plan-name {
  font-size: 1.5rem;
  font-weight: 900;
  margin-bottom: 8px;
  color: var(--text-main);
}

.plan-desc {
  font-size: 0.875rem;
  color: var(--text-muted);
  margin-bottom: 24px;
}

.plan-price {
  font-size: 3rem;
  font-weight: 900;
  color: var(--text-main);
  margin-bottom: 24px;
}

.plan-price span {
  font-size: 1rem;
  color: var(--text-muted);
  font-weight: 500;
}

.plan-features {
  list-style: none;
  margin-bottom: 32px;
  flex-grow: 1;
}

.plan-features li {
  margin-bottom: 14px;
  color: var(--text-muted);
  font-size: 0.95rem;
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 500;
}

.plan-features li svg {
  color: var(--primary-cyan);
  flex-shrink: 0;
}

.pricing-card .btn {
  width: 100%;
}

/* 用户评价 */
.reviews-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.review-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  padding: 32px;
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-card);
}

.review-stars {
  color: #f59e0b;
  margin-bottom: 16px;
  font-size: 1.1rem;
}

.review-content {
  color: var(--text-muted);
  font-size: 0.95rem;
  margin-bottom: 24px;
  font-style: italic;
  line-height: 1.7;
}

.user-info {
  display: flex;
  align-items: center;
  gap: 12px;
}

.user-avatar {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: var(--gradient-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 800;
  color: white;
  font-size: 1.1rem;
}

.user-details h4 {
  font-size: 0.95rem;
  font-weight: 800;
  color: var(--text-main);
}

.user-details p {
  font-size: 0.8125rem;
  color: var(--text-muted);
}

/* 常见问题 FAQ (原生 details/summary) */
.faq-list {
  max-width: 800px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.faq-item {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-card);
  overflow: hidden;
  transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

.faq-item:hover {
  border-color: var(--primary-blue);
  box-shadow: var(--shadow-hover);
}

.faq-item summary {
  padding: 24px;
  font-size: 1.125rem;
  font-weight: 700;
  color: var(--text-main);
  cursor: pointer;
  list-style: none;
  display: flex;
  align-items: center;
  justify-content: space-between;
  user-select: none;
}

.faq-item summary::-webkit-details-marker {
  display: none;
}

.faq-item summary::after {
  content: '+';
  font-size: 1.5rem;
  font-weight: 500;
  color: var(--primary-cyan);
  transition: transform 0.2s ease;
}

.faq-item[open] summary::after {
  content: '−';
}

.faq-answer {
  padding: 0 24px 24px;
  color: var(--text-muted);
  font-size: 0.975rem;
  border-top: 1px solid var(--border-color);
  margin-top: 4px;
  padding-top: 16px;
  line-height: 1.7;
}

/* 底栏 Footer (只保留 4 个链接) */
.footer {
  border-top: 1px solid var(--border-color);
  background: #f1f5f9;
  padding: 40px 0;
  text-align: center;
}

.footer-nav {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 40px;
  margin-bottom: 24px;
}

.footer-nav a {
  color: var(--text-muted);
  text-decoration: none;
  font-size: 1rem;
  font-weight: 600;
  transition: color 0.2s ease;
}

.footer-nav a:hover {
  color: var(--primary-cyan);
}

.footer-copyright {
  color: #64748b;
  font-size: 0.875rem;
}

/* 子页面独立通用布局 (about, terms, privacy, sitemap) */
.page-header {
  padding: 140px 0 60px;
  text-align: center;
  background: radial-gradient(circle at 50% 0%, #e0f2fe 0%, transparent 70%);
}

.page-title {
  font-size: 2.75rem;
  font-weight: 900;
  color: var(--text-main);
  margin-bottom: 16px;
}

.page-content {
  max-width: 860px;
  margin: 0 auto 100px;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-card);
  padding: 48px;
}

.page-content h2 {
  font-size: 1.5rem;
  color: var(--primary-cyan);
  margin: 32px 0 16px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--border-color);
}

.page-content h2:first-child {
  margin-top: 0;
}

.page-content p {
  color: var(--text-muted);
  margin-bottom: 16px;
  font-size: 1rem;
  line-height: 1.75;
}

.page-content ul {
  color: var(--text-muted);
  margin-bottom: 20px;
  padding-left: 24px;
}

.page-content li {
  margin-bottom: 8px;
  line-height: 1.6;
}

/* 响应式媒体查询 @media */
@media (max-width: 992px) {
  .hero-title {
    font-size: 2.75rem;
  }
  .advantages-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .pricing-grid {
    grid-template-columns: repeat(1, 1fr);
    max-width: 480px;
    margin: 0 auto;
  }
  .pricing-card.popular {
    transform: none;
  }
  .reviews-grid {
    grid-template-columns: repeat(1, 1fr);
  }
}

/* 高科技网格卡片 (Grid Cards) 文章布局 */
.articles-grid-header {
  text-align: center;
  margin: 60px 0 40px;
}

.articles-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  margin-bottom: 60px;
}

.article-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 28px 24px;
  box-shadow: var(--shadow-card);
  display: flex;
  flex-direction: column;
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  position: relative;
  overflow: hidden;
}

.article-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 3px;
  background: var(--gradient-primary);
  opacity: 0;
  transition: opacity 0.3s ease;
}

.article-card:hover {
  transform: translateY(-4px);
  border-color: var(--primary-cyan);
  box-shadow: var(--shadow-hover);
}

.article-card:hover::before {
  opacity: 1;
}

.card-meta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.8125rem;
  color: var(--text-muted);
  margin-bottom: 12px;
}

.card-tag {
  background: rgba(2, 132, 199, 0.08);
  color: var(--primary-cyan);
  border: 1px solid rgba(2, 132, 199, 0.2);
  padding: 3px 10px;
  border-radius: 20px;
  font-weight: 700;
  font-size: 0.75rem;
}

.card-title {
  font-size: 1.15rem;
  font-weight: 800;
  color: var(--text-main);
  margin-bottom: 12px;
  line-height: 1.4;
}

.card-title a {
  color: var(--text-main);
  text-decoration: none;
  transition: color 0.2s ease;
}

.card-title a:hover {
  color: var(--primary-cyan);
}

.card-excerpt {
  color: var(--text-muted);
  font-size: 0.9rem;
  line-height: 1.6;
  margin-bottom: 20px;
  flex-grow: 1;
}

.card-readmore {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  color: var(--primary-cyan);
  font-weight: 700;
  font-size: 0.9rem;
  text-decoration: none;
  transition: gap 0.2s ease;
}

.card-readmore:hover {
  gap: 10px;
  color: var(--primary-blue);
}

@media (max-width: 992px) {
  .articles-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 640px) {
  .articles-grid {
    grid-template-columns: 1fr;
  }
}