/* ==========================================================================
   寰宇云机场 - 独创宇宙星空与太空舱主题样式表 (Native CSS)
   规范：纯原生 CSS，零外部依赖，极速秒开，WCAG 2.1 AA 对比度合规
   ========================================================================== */

:root {
  --bg-primary: #080b18;
  --bg-secondary: #0f142a;
  --bg-card: rgba(19, 26, 53, 0.75);
  --bg-card-hover: rgba(28, 38, 77, 0.85);
  --border-color: rgba(99, 133, 255, 0.2);
  --border-hover: rgba(0, 242, 254, 0.5);
  
  --text-primary: #ffffff;
  --text-secondary: #cbd5e1;
  --text-muted: #94a3b8;
  
  --accent-cyan: #00f2fe;
  --accent-purple: #9d4edd;
  --accent-gold: #fbbf24;
  --accent-gradient: linear-gradient(135deg, #00f2fe 0%, #4facfe 50%, #9d4edd 100%);
  --card-gradient: linear-gradient(180deg, rgba(255, 255, 255, 0.05) 0%, rgba(255, 255, 255, 0.01) 100%);
  
  --shadow-glow: 0 0 25px rgba(0, 242, 254, 0.25);
  --shadow-card: 0 10px 30px -5px rgba(0, 0, 0, 0.5);
  
  --font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --container-max: 1200px;
}

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

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

body {
  font-family: var(--font-family);
  background-color: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.65;
  min-height: 100vh;
  position: relative;
  overflow-x: hidden;
  background-image: 
    radial-gradient(circle at 15% 15%, rgba(79, 70, 229, 0.18) 0%, transparent 40%),
    radial-gradient(circle at 85% 30%, rgba(0, 242, 254, 0.15) 0%, transparent 45%),
    radial-gradient(circle at 50% 80%, rgba(157, 78, 221, 0.18) 0%, transparent 50%),
    radial-gradient(1px 1px at 20px 30px, #ffffff 1px, transparent 0),
    radial-gradient(1.5px 1.5px at 120px 80px, #93c5fd 1.5px, transparent 0),
    radial-gradient(1px 1px at 240px 180px, #e0e7ff 1px, transparent 0),
    radial-gradient(1.5px 1.5px at 380px 240px, #67e8f9 1.5px, transparent 0);
  background-size: 100% 100%, 100% 100%, 100% 100%, 350px 350px, 450px 450px, 550px 550px, 650px 650px;
  background-attachment: fixed;
}

/* 动态流星/陨石特效 (纯 CSS，不消耗过多性能) */
.meteor-container {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  z-index: 0;
  overflow: hidden;
}

.meteor {
  position: absolute;
  top: 5%;
  width: 140px;
  height: 2px;
  background: linear-gradient(90deg, rgba(0, 242, 254, 0.8), rgba(255, 255, 255, 0.9), transparent);
  border-radius: 999px;
  filter: drop-shadow(0 0 6px #00f2fe);
  transform: rotate(-35deg);
  opacity: 0;
  animation: meteor-fall 8s infinite linear;
}

.meteor-1 { left: 40%; animation-delay: 1s; animation-duration: 9s; }
.meteor-2 { left: 75%; animation-delay: 4.5s; animation-duration: 7s; }
.meteor-3 { left: 20%; animation-delay: 7s; animation-duration: 11s; }

@keyframes meteor-fall {
  0% {
    transform: translate(100px, -100px) rotate(-35deg);
    opacity: 0;
  }
  5% {
    opacity: 1;
  }
  15% {
    transform: translate(-400px, 400px) rotate(-35deg);
    opacity: 0;
  }
  100% {
    opacity: 0;
  }
}

/* 尊重用户动效偏好 */
@media (prefers-reduced-motion: reduce) {
  .meteor {
    animation: none;
    display: none;
  }
  html {
    scroll-behavior: auto;
  }
}

/* 键盘无障碍跳过导航 */
.skip-link {
  position: absolute;
  top: -60px;
  left: 1rem;
  background: var(--accent-cyan);
  color: #050814;
  font-weight: 700;
  padding: 0.75rem 1.25rem;
  z-index: 9999;
  border-radius: var(--radius-sm);
  transition: top 0.2s ease;
  text-decoration: none;
}
.skip-link:focus {
  top: 1rem;
  outline: 3px solid #ffffff;
}

/* 容器与版心 */
.container {
  width: 100%;
  max-width: var(--container-max);
  margin-left: auto;
  margin-right: auto;
  padding-left: 1.5rem;
  padding-right: 1.5rem;
  position: relative;
  z-index: 1;
}

/* 锚点防遮挡 */
section[id], header[id] {
  scroll-margin-top: 90px;
}

/* 导航栏 Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: rgba(8, 11, 24, 0.85);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border-color);
  transition: background-color 0.3s;
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 74px;
}

.brand-logo {
  display: inline-flex;
  align-items: center;
  gap: 0.75rem;
  text-decoration: none;
  color: #ffffff;
  font-size: 1.35rem;
  font-weight: 800;
  letter-spacing: -0.02em;
}

.brand-capsule-svg {
  width: 36px;
  height: 36px;
  flex-shrink: 0;
  filter: drop-shadow(0 0 10px rgba(0, 242, 254, 0.6));
}

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

.nav-links {
  display: flex;
  align-items: center;
  list-style: none;
  gap: 1.5rem;
}

.nav-links a {
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 0.95rem;
  font-weight: 500;
  padding: 0.5rem 0.25rem;
  position: relative;
  transition: color 0.25s ease;
}

.nav-links a:hover,
.nav-links a:focus-visible {
  color: var(--accent-cyan);
  outline: none;
}

.nav-links a.active {
  color: var(--accent-cyan);
  font-weight: 600;
}

.nav-cta {
  display: inline-flex;
  align-items: center;
  justify-content: center;
}

/* 按钮规范 (满足 44px 触控要求) */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.75rem 1.6rem;
  min-height: 44px;
  min-width: 44px;
  font-size: 1rem;
  font-weight: 700;
  border-radius: var(--radius-sm);
  text-decoration: none;
  cursor: pointer;
  transition: all 0.25s ease;
  border: 1px solid transparent;
  text-align: center;
  white-space: nowrap;
  word-break: keep-all;
}

.btn-primary {
  background: var(--accent-gradient);
  color: #060914;
  box-shadow: 0 4px 20px rgba(0, 242, 254, 0.35);
}

.btn-primary:hover,
.btn-primary:focus-visible {
  transform: translateY(-2px);
  box-shadow: 0 6px 28px rgba(0, 242, 254, 0.5);
  outline: 2px solid #ffffff;
}

.btn-outline {
  background: rgba(255, 255, 255, 0.05);
  color: #ffffff;
  border: 1px solid var(--border-color);
}

.btn-outline:hover,
.btn-outline:focus-visible {
  background: rgba(255, 255, 255, 0.12);
  border-color: var(--accent-cyan);
  color: var(--accent-cyan);
  outline: 2px solid var(--accent-cyan);
}

.btn-large {
  padding: 0.95rem 2.2rem;
  font-size: 1.1rem;
  border-radius: var(--radius-md);
}

/* 主视觉区 (Hero Section) */
.hero-section {
  padding: 5rem 0 4rem;
  text-align: center;
  position: relative;
}

.hero-capsule-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  background: rgba(0, 242, 254, 0.1);
  border: 1px solid rgba(0, 242, 254, 0.3);
  padding: 0.35rem 1rem;
  border-radius: 999px;
  color: var(--accent-cyan);
  font-size: 0.88rem;
  font-weight: 600;
  margin-bottom: 1.75rem;
}

.pulse-dot {
  width: 8px;
  height: 8px;
  background-color: var(--accent-cyan);
  border-radius: 50%;
  box-shadow: 0 0 10px var(--accent-cyan);
}

.hero-title {
  font-size: clamp(2.1rem, 4.5vw, 3.6rem);
  font-weight: 850;
  line-height: 1.22;
  letter-spacing: -0.03em;
  margin-bottom: 1.25rem;
  max-width: 900px;
  margin-left: auto;
  margin-right: auto;
}

.hero-subtitle {
  font-size: clamp(1.05rem, 2vw, 1.3rem);
  color: var(--text-secondary);
  max-width: 760px;
  margin: 0 auto 1.5rem auto;
  font-weight: 400;
}

.hero-desc {
  font-size: 0.98rem;
  color: var(--text-muted);
  max-width: 720px;
  margin: 0 auto 2.25rem auto;
  line-height: 1.7;
}

.hero-actions {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 1.2rem;
  flex-wrap: wrap;
  margin-bottom: 3rem;
}

.hero-metrics {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1.5rem;
  max-width: 860px;
  margin: 2rem auto 0;
  padding: 1.5rem;
  background: var(--bg-card);
  backdrop-filter: blur(12px);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
}

.metric-item {
  text-align: center;
}

.metric-number {
  font-size: 1.75rem;
  font-weight: 800;
  background: var(--accent-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.metric-label {
  font-size: 0.82rem;
  color: var(--text-muted);
  margin-top: 0.25rem;
}

/* 区块通用结构 */
.section {
  padding: 5rem 0;
}

.section-alt {
  background: rgba(15, 20, 42, 0.45);
  border-top: 1px solid rgba(255, 255, 255, 0.05);
  border-bottom: 1px solid rgba(255, 255, 255, 0.05);
}

.section-header {
  text-align: center;
  max-width: 700px;
  margin: 0 auto 3.5rem;
}

.section-tag {
  color: var(--accent-cyan);
  font-size: 0.88rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: 0.5rem;
}

.section-title {
  font-size: clamp(1.8rem, 3.2vw, 2.4rem);
  font-weight: 800;
  letter-spacing: -0.02em;
  margin-bottom: 0.75rem;
}

.section-subtitle {
  color: var(--text-secondary);
  font-size: 1rem;
}

/* 核心优势卡片 (3 个图文卡片) */
.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2rem;
}

.feature-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 2.25rem 1.75rem;
  transition: transform 0.3s ease, border-color 0.3s ease, box-shadow 0.3s ease;
  position: relative;
  overflow: hidden;
}

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

.feature-icon-box {
  width: 58px;
  height: 58px;
  background: rgba(0, 242, 254, 0.12);
  border: 1px solid rgba(0, 242, 254, 0.3);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 1.5rem;
  color: var(--accent-cyan);
}

.feature-card h3 {
  font-size: 1.28rem;
  font-weight: 700;
  margin-bottom: 0.75rem;
}

.feature-card p {
  color: var(--text-secondary);
  font-size: 0.95rem;
  line-height: 1.6;
}

/* 流媒体与 AI 支持图卡 */
.support-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 2rem;
}

.support-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 2.25rem;
}

.support-card-header {
  display: flex;
  align-items: center;
  gap: 1rem;
  margin-bottom: 1.25rem;
}

.support-card-header h3 {
  font-size: 1.35rem;
  font-weight: 750;
}

.support-pill-list {
  display: flex;
  flex-wrap: wrap;
  gap: 0.65rem;
  margin-top: 1.25rem;
}

.support-pill {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(255, 255, 255, 0.1);
  padding: 0.45rem 0.9rem;
  border-radius: 999px;
  font-size: 0.88rem;
  color: var(--text-secondary);
}

.support-pill svg {
  width: 16px;
  height: 16px;
  fill: currentColor;
}

/* 真实套餐对比表 */
.pricing-wrapper {
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-card);
}

.pricing-table {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
  min-width: 640px;
}

.pricing-table caption {
  caption-side: top;
  text-align: left;
  padding: 1.25rem 1.5rem;
  font-size: 0.9rem;
  color: var(--text-muted);
  border-bottom: 1px solid rgba(255, 255, 255, 0.05);
}

.pricing-table th,
.pricing-table td {
  padding: 1.25rem 1.5rem;
  border-bottom: 1px solid rgba(255, 255, 255, 0.06);
}

.pricing-table td:last-child {
  white-space: nowrap;
}

.pricing-table .btn {
  white-space: nowrap;
  word-break: keep-all;
  min-width: 110px;
}

.pricing-table th {
  background: rgba(255, 255, 255, 0.03);
  font-size: 0.92rem;
  color: var(--text-muted);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.pricing-plan-name {
  font-size: 1.15rem;
  font-weight: 800;
  color: #ffffff;
}

.pricing-plan-name .badge-hot {
  font-size: 0.72rem;
  padding: 0.15rem 0.5rem;
  border-radius: 4px;
  background: #ef4444;
  color: #ffffff;
  margin-left: 0.4rem;
  vertical-align: middle;
}

.pricing-price {
  font-size: 1.45rem;
  font-weight: 800;
  color: var(--accent-cyan);
}

.pricing-price span {
  font-size: 0.85rem;
  color: var(--text-muted);
  font-weight: 400;
}

/* 用户评价 */
.reviews-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.75rem;
}

.review-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 1.75rem;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.review-stars {
  color: var(--accent-gold);
  font-size: 1.1rem;
  margin-bottom: 0.75rem;
}

.review-text {
  font-size: 0.95rem;
  color: var(--text-secondary);
  line-height: 1.6;
  margin-bottom: 1.25rem;
  font-style: italic;
}

.review-author {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.author-avatar {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: linear-gradient(135deg, #4f46e5, #06b6d4);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 0.95rem;
  color: #ffffff;
}

.author-info h4 {
  font-size: 0.92rem;
  font-weight: 600;
}

.author-info p {
  font-size: 0.78rem;
  color: var(--text-muted);
}

/* FAQ 常见问题解答 (原生 details / summary, 默认 open) */
.faq-list {
  max-width: 860px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.faq-item {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  overflow: hidden;
  transition: border-color 0.25s ease;
}

.faq-item[open] {
  border-color: rgba(0, 242, 254, 0.4);
}

.faq-summary {
  padding: 1.2rem 1.5rem;
  font-weight: 700;
  font-size: 1.05rem;
  cursor: pointer;
  list-style: none;
  display: flex;
  justify-content: space-between;
  align-items: center;
  user-select: none;
  color: #ffffff;
}

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

.faq-summary::after {
  content: "+";
  font-size: 1.4rem;
  font-weight: 400;
  color: var(--accent-cyan);
  transition: transform 0.2s ease;
}

.faq-item[open] .faq-summary::after {
  content: "−";
  transform: rotate(180deg);
}

.faq-content {
  padding: 0 1.5rem 1.25rem 1.5rem;
  color: var(--text-secondary);
  font-size: 0.95rem;
  line-height: 1.65;
  border-top: 1px solid rgba(255, 255, 255, 0.04);
  margin-top: 0.25rem;
  padding-top: 1rem;
}

.faq-content a {
  color: var(--accent-cyan);
  text-decoration: underline;
  text-underline-offset: 3px;
}

/* 页脚 Footer */
.site-footer {
  background: #04060d;
  border-top: 1px solid rgba(255, 255, 255, 0.08);
  padding: 4rem 0 2.5rem;
  margin-top: 5rem;
}

.footer-top {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 2rem;
  padding-bottom: 2.5rem;
  border-bottom: 1px solid rgba(255, 255, 255, 0.06);
}

.footer-brand {
  max-width: 380px;
}

.footer-brand p {
  color: var(--text-muted);
  font-size: 0.88rem;
  margin-top: 0.75rem;
  line-height: 1.6;
}

.footer-links {
  display: flex;
  gap: 2.25rem;
  list-style: none;
  flex-wrap: wrap;
}

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

.footer-links a:hover,
.footer-links a:focus-visible {
  color: var(--accent-cyan);
  outline: none;
}

.footer-bottom {
  padding-top: 2rem;
  text-align: center;
  color: var(--text-muted);
  font-size: 0.82rem;
}

/* 文章正文 / 子页面专用通用排版 */
.content-wrapper {
  max-width: 860px;
  margin: 3rem auto;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 2.5rem 2rem;
}

.breadcrumb {
  display: flex;
  gap: 0.5rem;
  font-size: 0.88rem;
  color: var(--text-muted);
  margin-bottom: 1.5rem;
  list-style: none;
}

.breadcrumb a {
  color: var(--accent-cyan);
  text-decoration: none;
}

.article-header {
  margin-bottom: 2rem;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  padding-bottom: 1.5rem;
}

.article-header h1 {
  font-size: clamp(1.8rem, 3vw, 2.3rem);
  line-height: 1.3;
  margin-bottom: 0.75rem;
}

.article-meta {
  font-size: 0.85rem;
  color: var(--text-muted);
  display: flex;
  gap: 1.5rem;
  flex-wrap: wrap;
}

.article-body {
  color: var(--text-secondary);
  font-size: 1.02rem;
  line-height: 1.8;
}

.article-body h2 {
  font-size: 1.45rem;
  color: #ffffff;
  margin: 2rem 0 1rem;
  border-left: 4px solid var(--accent-cyan);
  padding-left: 0.75rem;
}

.article-body h3 {
  font-size: 1.2rem;
  color: #ffffff;
  margin: 1.5rem 0 0.75rem;
}

.article-body p {
  margin-bottom: 1.25rem;
}

.article-body ul, .article-body ol {
  margin: 0 0 1.25rem 1.5rem;
}

.article-body li {
  margin-bottom: 0.4rem;
}

.article-body blockquote {
  border-left: 4px solid var(--accent-purple);
  background: rgba(157, 78, 221, 0.1);
  padding: 1rem 1.25rem;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  margin: 1.5rem 0;
  font-size: 0.95rem;
  color: #e2e8f0;
}

.article-body a {
  color: var(--accent-cyan);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.article-cta-box {
  margin: 2.5rem 0;
  padding: 1.75rem;
  background: linear-gradient(135deg, rgba(0, 242, 254, 0.1) 0%, rgba(157, 78, 221, 0.15) 100%);
  border: 1px solid rgba(0, 242, 254, 0.35);
  border-radius: var(--radius-md);
  text-align: center;
}

/* 知识科普目录卡片网格 */
.knowledge-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.75rem;
}

.knowledge-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 1.75rem;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  transition: transform 0.25s ease, border-color 0.25s ease;
}

.knowledge-card:hover {
  transform: translateY(-4px);
  border-color: var(--accent-cyan);
}

.knowledge-card-tag {
  font-size: 0.78rem;
  color: var(--accent-cyan);
  font-weight: 700;
  text-transform: uppercase;
  margin-bottom: 0.5rem;
}

.knowledge-card h3 {
  font-size: 1.15rem;
  font-weight: 700;
  line-height: 1.4;
  margin-bottom: 0.75rem;
  color: #ffffff;
}

.knowledge-card p {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.6;
  margin-bottom: 1.25rem;
  flex-grow: 1;
}

.knowledge-card .read-more {
  color: var(--accent-cyan);
  font-weight: 600;
  text-decoration: none;
  font-size: 0.9rem;
  display: inline-flex;
  align-items: center;
  gap: 0.25rem;
}

/* 响应式断点适配 */
@media (max-width: 1024px) {
  .features-grid,
  .reviews-grid,
  .knowledge-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .hero-metrics {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  .nav-inner {
    height: auto;
    padding: 1rem 0;
    flex-direction: column;
    gap: 1rem;
  }
  .nav-links {
    gap: 1rem;
    flex-wrap: wrap;
    justify-content: center;
  }
  .features-grid,
  .support-grid,
  .reviews-grid,
  .knowledge-grid {
    grid-template-columns: 1fr;
  }
  .hero-section {
    padding: 3rem 0 2rem;
  }
  .hero-title {
    font-size: 2rem;
  }
  .hero-actions {
    flex-direction: column;
    width: 100%;
  }
  .hero-actions .btn {
    width: 100%;
  }
  .footer-top {
    flex-direction: column;
    text-align: center;
  }
  .footer-links {
    justify-content: center;
    gap: 1.5rem;
  }
}

@media (max-width: 390px) {
  .container {
    padding-left: 1rem;
    padding-right: 1rem;
  }
  .hero-metrics {
    grid-template-columns: 1fr;
    gap: 1rem;
  }
  .content-wrapper {
    padding: 1.75rem 1.25rem;
  }
}