/* ==========================================================================
   青云梯官网 - 核心样式表 (style.css)
   极简无依赖、极致加载速度、纯原生CSS、响应式设计
   ========================================================================== */

:root {
  --primary-color: #2563eb;
  --primary-hover: #1d4ed8;
  --primary-light: #eff6ff;
  --accent-color: #06b6d4;
  --accent-gradient: linear-gradient(135deg, #2563eb 0%, #06b6d4 100%);
  --bg-dark: #0b0f19;
  --bg-card: #111827;
  --bg-card-hover: #1f2937;
  --bg-body: #0b0f19;
  --text-main: #f3f4f6;
  --text-muted: #9ca3af;
  --text-light: #ffffff;
  --border-color: #1f2937;
  --border-highlight: #374151;
  --success-color: #10b981;
  --warning-color: #f59e0b;
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.3), 0 2px 4px -1px rgba(0, 0, 0, 0.2);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.5), 0 4px 6px -2px rgba(0, 0, 0, 0.3);
  --shadow-glow: 0 0 25px rgba(37, 99, 235, 0.25);
  --radius-sm: 6px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-full: 9999px;
  --container-width: 1200px;
  --header-height: 72px;
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif, "Apple Color Emoji", "Segoe UI Emoji";
}

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

html {
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.6;
  color: var(--text-main);
  background-color: var(--bg-body);
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-height) + 16px);
}

body {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  overflow-x: hidden;
  background-color: var(--bg-body);
  color: var(--text-main);
}

/* 针对降低动画偏好 */
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}

/* 键盘无障碍跳过导航 */
.skip-link {
  position: absolute;
  top: -100px;
  left: 16px;
  background: var(--primary-color);
  color: #fff;
  padding: 12px 20px;
  z-index: 9999;
  border-radius: var(--radius-sm);
  text-decoration: none;
  font-weight: 600;
  transition: top 0.2s ease;
}
.skip-link:focus {
  top: 16px;
  outline: 3px solid #60a5fa;
}

/* 链接全局规范 */
a {
  color: #60a5fa;
  text-decoration: none;
  transition: color 0.2s ease;
}
a:hover {
  color: #93c5fd;
  text-decoration: underline;
}
a:focus-visible, button:focus-visible, summary:focus-visible {
  outline: 2px solid #60a5fa;
  outline-offset: 4px;
}

/* 容器 */
.container {
  width: 100%;
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 20px;
}

/* 顶部导航 */
.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background-color: rgba(11, 15, 25, 0.92);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-color);
  height: var(--header-height);
  display: flex;
  align-items: center;
}
.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
}
.brand-logo {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 1.35rem;
  font-weight: 700;
  color: var(--text-light);
  text-decoration: none;
}
.brand-logo:hover {
  text-decoration: none;
}
.brand-logo-img {
  width: 36px;
  height: 36px;
  border-radius: 9px;
  display: block;
  flex-shrink: 0;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.4), 0 0 16px rgba(6, 182, 212, 0.35);
  transition: transform 0.25s cubic-bezier(0.16, 1, 0.3, 1), box-shadow 0.25s ease;
}
.brand-logo:hover .brand-logo-img {
  transform: translateY(-1px) scale(1.06);
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.5), 0 0 24px rgba(56, 189, 248, 0.65);
}
.brand-icon {
  display: none;
}
.main-nav {
  display: flex;
  align-items: center;
  gap: 24px;
}
.nav-list {
  display: flex;
  list-style: none;
  align-items: center;
  gap: 20px;
}
.nav-link {
  color: var(--text-muted);
  font-size: 0.95rem;
  font-weight: 500;
  padding: 8px 12px;
  border-radius: var(--radius-sm);
  transition: all 0.2s ease;
}
.nav-link:hover, .nav-link.active {
  color: var(--text-light);
  background-color: rgba(255, 255, 255, 0.05);
  text-decoration: none;
}
.nav-badge {
  background: rgba(37, 99, 235, 0.2);
  color: #60a5fa;
  border: 1px solid rgba(37, 99, 235, 0.4);
  font-size: 0.75rem;
  padding: 2px 6px;
  border-radius: 4px;
  margin-left: 4px;
}

/* 按钮体系 */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 24px;
  min-height: 44px;
  min-width: 44px;
  font-size: 0.95rem;
  font-weight: 600;
  border-radius: var(--radius-md);
  text-decoration: none;
  cursor: pointer;
  border: 1px solid transparent;
  transition: all 0.2s ease;
  line-height: 1;
}
.btn:hover {
  text-decoration: none;
}
.btn-primary {
  background: var(--accent-gradient);
  color: #ffffff;
  box-shadow: 0 4px 14px rgba(37, 99, 235, 0.35);
}
.btn-primary:hover {
  opacity: 0.92;
  transform: translateY(-1px);
  box-shadow: 0 6px 20px rgba(37, 99, 235, 0.45);
  color: #fff;
}
.btn-secondary {
  background-color: var(--bg-card);
  color: var(--text-main);
  border-color: var(--border-highlight);
}
.btn-secondary:hover {
  background-color: var(--bg-card-hover);
  color: var(--text-light);
  border-color: #4b5563;
}
.btn-sm {
  padding: 8px 16px;
  font-size: 0.875rem;
  min-height: 40px;
}
.btn-lg {
  padding: 16px 32px;
  font-size: 1.05rem;
  min-height: 52px;
}

/* 主视觉区 (Hero Section) - 超级巨树破云入霄第一视角高清背景 */
.hero-section {
  position: relative;
  padding: 90px 0 70px;
  text-align: center;
  overflow: hidden;
  border-bottom: 1px solid var(--border-color);
  background-image: 
    linear-gradient(180deg, rgba(11, 15, 25, 0.75) 0%, rgba(11, 15, 25, 0.85) 65%, rgba(11, 15, 25, 0.98) 100%),
    radial-gradient(circle at 50% 25%, rgba(6, 182, 212, 0.2) 0%, rgba(11, 15, 25, 0) 75%),
    url('hero-tree.jpg');
  background-size: cover;
  background-position: center bottom;
  background-repeat: no-repeat;
}
.hero-tag {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 16px;
  background-color: rgba(37, 99, 235, 0.12);
  border: 1px solid rgba(37, 99, 235, 0.3);
  border-radius: var(--radius-full);
  color: #93c5fd;
  font-size: 0.875rem;
  font-weight: 500;
  margin-bottom: 24px;
}
.hero-tag-pulse {
  width: 8px;
  height: 8px;
  background-color: var(--success-color);
  border-radius: 50%;
  box-shadow: 0 0 8px var(--success-color);
}
.hero-title {
  margin-bottom: 22px;
  line-height: 1.15;
}
.hero-title-main {
  display: block;
  font-size: clamp(2.3rem, 5.5vw, 3.8rem);
  font-weight: 800;
  letter-spacing: -0.02em;
  color: #ffffff;
  margin-bottom: 12px;
  text-shadow: 0 4px 20px rgba(0, 0, 0, 0.85);
}
.hero-title-sub {
  display: block;
  font-size: clamp(1.4rem, 3.6vw, 2.3rem);
  font-weight: 800;
  letter-spacing: -0.01em;
  line-height: 1.35;
  filter: drop-shadow(0 0 16px rgba(56, 189, 248, 0.45));
}
.text-gradient {
  background: linear-gradient(135deg, #38bdf8 0%, #22d3ee 45%, #67e8f9 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  color: #38bdf8;
}
.hero-subtitle {
  font-size: clamp(1.1rem, 2.5vw, 1.35rem);
  color: #93c5fd;
  font-weight: 600;
  margin-bottom: 18px;
}
.hero-desc {
  max-width: 780px;
  margin: 0 auto 36px;
  font-size: 1.05rem;
  color: var(--text-muted);
  line-height: 1.7;
}
.hero-cta-group {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  flex-wrap: wrap;
  margin-bottom: 40px;
}
.hero-metrics {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  max-width: 900px;
  margin: 0 auto;
  padding: 24px;
  background-color: rgba(17, 24, 39, 0.6);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
}
.metric-item {
  text-align: center;
}
.metric-value {
  font-size: 1.75rem;
  font-weight: 700;
  color: var(--text-light);
  margin-bottom: 4px;
}
.metric-label {
  font-size: 0.85rem;
  color: var(--text-muted);
}

/* 通用区块 */
.section {
  padding: 80px 0;
  border-bottom: 1px solid var(--border-color);
}
.section-header {
  text-align: center;
  max-width: 760px;
  margin: 0 auto 50px;
}
.section-tag {
  color: #60a5fa;
  font-size: 0.875rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 8px;
  display: inline-block;
}
.section-title {
  font-size: clamp(1.75rem, 3.5vw, 2.4rem);
  font-weight: 700;
  color: var(--text-light);
  margin-bottom: 16px;
  line-height: 1.3;
}
.section-desc {
  color: var(--text-muted);
  font-size: 1.05rem;
}

/* 核心优势卡片 (3个图文卡片) */
.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
}
.feature-card {
  background-color: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 32px 24px;
  transition: transform 0.2s ease, border-color 0.2s ease, box-shadow 0.2s ease;
  display: flex;
  flex-direction: column;
}
.feature-card:hover {
  transform: translateY(-4px);
  border-color: #3b82f6;
  box-shadow: var(--shadow-glow);
}
.feature-icon-wrapper {
  width: 56px;
  height: 56px;
  border-radius: var(--radius-md);
  background: rgba(37, 99, 235, 0.15);
  border: 1px solid rgba(37, 99, 235, 0.3);
  display: flex;
  align-items: center;
  justify-content: center;
  color: #60a5fa;
  margin-bottom: 20px;
}
.feature-card h3 {
  font-size: 1.3rem;
  color: var(--text-light);
  margin-bottom: 12px;
}
.feature-card p {
  color: var(--text-muted);
  font-size: 0.95rem;
  line-height: 1.6;
  margin-bottom: 20px;
  flex-grow: 1;
}
.feature-list {
  list-style: none;
  padding-top: 16px;
  border-top: 1px solid rgba(255, 255, 255, 0.06);
}
.feature-list li {
  display: flex;
  align-items: center;
  gap: 8px;
  color: #d1d5db;
  font-size: 0.875rem;
  margin-bottom: 8px;
}
.feature-list li:last-child {
  margin-bottom: 0;
}
.check-icon {
  color: var(--success-color);
  font-weight: bold;
}

/* 流媒体与AI支持卡片 */
.media-ai-container {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 32px;
}
.media-ai-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 36px 30px;
}
.media-ai-card h3 {
  font-size: 1.4rem;
  color: var(--text-light);
  margin-bottom: 14px;
  display: flex;
  align-items: center;
  gap: 10px;
}
.media-ai-card p {
  color: var(--text-muted);
  margin-bottom: 24px;
}
.app-badges {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}
.app-badge {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 8px 16px;
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  font-size: 0.875rem;
  color: var(--text-main);
  font-weight: 500;
}
.app-badge-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background-color: var(--success-color);
}

/* 套餐价格对比表 */
.pricing-section {
  background: radial-gradient(circle at 50% 90%, rgba(6, 182, 212, 0.08) 0%, rgba(11, 15, 25, 0) 70%);
}
.pricing-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  align-items: stretch;
}
.pricing-card {
  background-color: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 32px 24px;
  display: flex;
  flex-direction: column;
  position: relative;
  transition: transform 0.2s ease, border-color 0.2s ease;
}
.pricing-card.featured {
  border-color: #2563eb;
  background: linear-gradient(180deg, rgba(37, 99, 235, 0.08) 0%, var(--bg-card) 100%);
  box-shadow: 0 8px 24px rgba(37, 99, 235, 0.2);
}
.pricing-badge {
  position: absolute;
  top: -12px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--accent-gradient);
  color: #fff;
  padding: 4px 14px;
  border-radius: var(--radius-full);
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.05em;
  white-space: nowrap;
}
.pricing-header {
  text-align: center;
  padding-bottom: 20px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  margin-bottom: 24px;
}
.pricing-name {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-light);
  margin-bottom: 10px;
}
.pricing-price {
  font-size: 2.5rem;
  font-weight: 800;
  color: var(--text-light);
  line-height: 1;
  margin-bottom: 8px;
}
.pricing-price span {
  font-size: 0.95rem;
  font-weight: normal;
  color: var(--text-muted);
}
.pricing-desc {
  font-size: 0.85rem;
  color: var(--text-muted);
}
.pricing-features {
  list-style: none;
  margin-bottom: 28px;
  flex-grow: 1;
}
.pricing-features li {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  margin-bottom: 12px;
  font-size: 0.9rem;
  color: #d1d5db;
}
.pricing-features li:last-child {
  margin-bottom: 0;
}
.pricing-card .btn {
  width: 100%;
}

/* 用户评价 (Testimonials) */
.testimonials-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}
.testimonial-card {
  background-color: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 28px;
  display: flex;
  flex-direction: column;
}
.rating-stars {
  color: #f59e0b;
  font-size: 1rem;
  margin-bottom: 14px;
  letter-spacing: 2px;
}
.testimonial-text {
  color: #d1d5db;
  font-size: 0.95rem;
  line-height: 1.6;
  margin-bottom: 20px;
  flex-grow: 1;
}
.testimonial-user {
  display: flex;
  align-items: center;
  gap: 12px;
}
.user-avatar {
  width: 42px;
  height: 42px;
  border-radius: 50%;
  background: rgba(37, 99, 235, 0.2);
  color: #60a5fa;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1rem;
  border: 1px solid rgba(37, 99, 235, 0.3);
}
.user-info h4 {
  font-size: 0.95rem;
  color: var(--text-light);
  margin-bottom: 2px;
}
.user-info p {
  font-size: 0.8rem;
  color: var(--text-muted);
}

/* FAQ 常见问题解答 (全部默认展开) */
.faq-list {
  max-width: 860px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 16px;
}
.faq-item {
  background-color: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  overflow: hidden;
  transition: border-color 0.2s ease;
}
.faq-item[open] {
  border-color: var(--border-highlight);
}
.faq-item summary {
  padding: 20px 24px;
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--text-light);
  cursor: pointer;
  list-style: none;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  position: relative;
  user-select: none;
}
.faq-item summary::-webkit-details-marker {
  display: none;
}
.faq-item summary::after {
  content: "▾";
  font-size: 1.2rem;
  color: #60a5fa;
  transition: transform 0.2s ease;
}
.faq-item[open] summary::after {
  transform: rotate(180deg);
}
.faq-content {
  padding: 0 24px 20px;
  color: var(--text-muted);
  font-size: 0.95rem;
  line-height: 1.7;
  border-top: 1px solid rgba(255, 255, 255, 0.04);
  padding-top: 14px;
}
.faq-content p {
  margin-bottom: 10px;
}
.faq-content p:last-child {
  margin-bottom: 0;
}

/* 页脚 Footer - 规范要求严格只保留四个链接打开新页面 */
.site-footer {
  background-color: #060911;
  border-top: 1px solid var(--border-color);
  padding: 40px 0 30px;
  margin-top: auto;
}
.footer-inner {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 24px;
  text-align: center;
}
.footer-nav {
  display: flex;
  align-items: center;
  justify-content: center;
  flex-wrap: wrap;
  gap: 32px;
}
.footer-link {
  color: var(--text-muted);
  font-size: 0.95rem;
  font-weight: 500;
  padding: 6px 10px;
  transition: color 0.2s ease;
}
.footer-link:hover {
  color: var(--text-light);
  text-decoration: underline;
}
.footer-copy {
  color: #6b7280;
  font-size: 0.85rem;
}

/* 独立内容页基础排版 (About, Terms, Privacy, Sitemap, Knowledge, Articles) */
.page-header {
  padding: 60px 0 40px;
  text-align: center;
  background: radial-gradient(circle at 50% 0%, rgba(37, 99, 235, 0.12) 0%, rgba(11, 15, 25, 0) 70%);
  border-bottom: 1px solid var(--border-color);
}
.breadcrumb {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  font-size: 0.875rem;
  color: var(--text-muted);
  margin-bottom: 16px;
}
.breadcrumb a {
  color: var(--text-muted);
}
.breadcrumb a:hover {
  color: #60a5fa;
}
.content-wrapper {
  max-width: 860px;
  margin: 50px auto;
  background-color: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 40px;
}
.prose {
  color: #d1d5db;
  font-size: 1.05rem;
  line-height: 1.8;
}
.prose h2 {
  font-size: 1.5rem;
  color: var(--text-light);
  margin: 36px 0 16px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--border-color);
}
.prose h3 {
  font-size: 1.25rem;
  color: var(--text-light);
  margin: 28px 0 12px;
}
.prose p {
  margin-bottom: 18px;
}
.prose ul, .prose ol {
  margin: 0 0 20px 24px;
}
.prose li {
  margin-bottom: 8px;
}
.prose blockquote {
  border-left: 4px solid var(--primary-color);
  padding: 12px 20px;
  background: rgba(37, 99, 235, 0.08);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  margin: 24px 0;
  color: #93c5fd;
}
.article-meta {
  display: flex;
  align-items: center;
  gap: 16px;
  font-size: 0.875rem;
  color: var(--text-muted);
  margin-bottom: 24px;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--border-color);
}
.article-faq-box {
  margin-top: 40px;
  padding-top: 30px;
  border-top: 1px solid var(--border-color);
}
.article-faq-box h3 {
  font-size: 1.3rem;
  color: var(--text-light);
  margin-bottom: 20px;
}

/* 知识科普专栏文章列表 */
.article-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
  margin: 40px 0;
}
.article-card {
  background-color: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 24px;
  display: flex;
  flex-direction: column;
  transition: transform 0.2s ease, border-color 0.2s ease;
}
.article-card:hover {
  transform: translateY(-4px);
  border-color: #3b82f6;
}
.article-card-tag {
  font-size: 0.75rem;
  color: #60a5fa;
  font-weight: 600;
  margin-bottom: 10px;
}
.article-card-title {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--text-light);
  line-height: 1.4;
  margin-bottom: 12px;
}
.article-card-desc {
  font-size: 0.9rem;
  color: var(--text-muted);
  line-height: 1.6;
  margin-bottom: 20px;
  flex-grow: 1;
}
.article-card-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.8rem;
  color: #6b7280;
  border-top: 1px solid rgba(255, 255, 255, 0.05);
  padding-top: 12px;
}

/* 网站地图列表卡片 */
.sitemap-section-card {
  background-color: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 28px;
  margin-bottom: 24px;
}
.sitemap-section-card h3 {
  font-size: 1.25rem;
  color: var(--text-light);
  margin-bottom: 16px;
  padding-bottom: 8px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}
.sitemap-links-list {
  list-style: none;
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 14px;
}
.sitemap-links-list li a {
  display: flex;
  align-items: center;
  gap: 8px;
  color: #d1d5db;
  font-size: 0.95rem;
}
.sitemap-links-list li a:hover {
  color: #60a5fa;
}

/* 响应式媒体查询 @media */
@media (max-width: 1024px) {
  .features-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .pricing-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .hero-metrics {
    grid-template-columns: repeat(2, 1fr);
  }
  .article-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  :root {
    --header-height: 64px;
  }
  .main-nav {
    display: none; /* 移动端紧凑模式 */
  }
  .mobile-cta {
    display: inline-flex !important;
  }
  .features-grid, .pricing-grid, .testimonials-grid, .article-grid, .media-ai-container {
    grid-template-columns: 1fr;
  }
  .hero-section {
    padding: 50px 0 40px;
  }
  .hero-title {
    font-size: 2rem;
  }
  .hero-subtitle {
    font-size: 1.1rem;
  }
  .hero-metrics {
    grid-template-columns: 1fr 1fr;
    gap: 12px;
    padding: 16px;
  }
  .metric-value {
    font-size: 1.4rem;
  }
  .section {
    padding: 50px 0;
  }
  .content-wrapper {
    padding: 24px 16px;
    margin: 24px auto;
  }
  .footer-nav {
    gap: 16px;
    flex-direction: column;
  }
  .sitemap-links-list {
    grid-template-columns: 1fr;
  }
  .btn {
    width: 100%;
    min-height: 48px;
  }
  .hero-cta-group {
    flex-direction: column;
    width: 100%;
  }
  .hero-cta-group .btn {
    width: 100%;
  }
}

@media (max-width: 480px) {
  .hero-title {
    font-size: 1.75rem;
  }
  .hero-metrics {
    grid-template-columns: 1fr;
  }
}

/* ==========================================================================
   全景萤火闪烁特效 (Panoramic Fireflies Animation)
   ========================================================================== */
#fireflies-canvas {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  pointer-events: none;
  z-index: 99;
  opacity: 0.9;
}

@media (prefers-reduced-motion: reduce) {
  #fireflies-canvas {
    display: none !important;
  }
}