/* ==========================================================================
   奈云 (NaiYun Cyber) - Neo-Cyberpunk Style Sheet
   Pure CSS3 - Fast Loading, No Heavy Framework Dependencies
   ========================================================================== */

/* 1. 全局变量与 CSS Reset */
:root {
  --bg-main: #07080f;
  --bg-surface: #0d101d;
  --bg-card: rgba(15, 22, 41, 0.75);
  --bg-card-hover: rgba(22, 33, 62, 0.85);
  
  --cyan-neon: #00f0ff;
  --cyan-glow: rgba(0, 240, 255, 0.4);
  --magenta-neon: #ff007f;
  --magenta-glow: rgba(255, 0, 127, 0.4);
  --purple-neon: #8b5cf6;
  --purple-glow: rgba(139, 92, 246, 0.4);
  
  --text-bright: #ffffff;
  --text-main: #e2e8f0;
  --text-muted: #94a3b8;
  --text-dim: #64748b;

  --border-cyber: rgba(0, 240, 255, 0.2);
  --border-glow: rgba(0, 240, 255, 0.6);
  --border-magenta: rgba(255, 0, 127, 0.3);

  --radius-sm: 6px;
  --radius-md: 12px;
  --radius-lg: 20px;
  
  --font-main: system-ui, -apple-system, BlinkMacSystemFont, "SF Pro Text", "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
  background-color: var(--bg-main);
  color: var(--text-main);
  font-family: var(--font-main);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

body {
  overflow-x: hidden;
  background-image: 
    radial-gradient(circle at 15% 15%, rgba(139, 92, 246, 0.12) 0%, transparent 40%),
    radial-gradient(circle at 85% 65%, rgba(0, 240, 255, 0.12) 0%, transparent 45%),
    radial-gradient(circle at 50% 90%, rgba(255, 0, 127, 0.08) 0%, transparent 50%),
    linear-gradient(to right, rgba(255, 255, 255, 0.02) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(255, 255, 255, 0.02) 1px, transparent 1px);
  background-size: 100% 100%, 100% 100%, 100% 100%, 40px 40px, 40px 40px;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

a {
  color: inherit;
  text-decoration: none;
  transition: var(--transition);
}

ul {
  list-style: none;
}

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

/* 2. 通用布局组件 */
.container {
  width: 100%;
  max-width: 1240px;
  margin: 0 auto;
  padding: 0 24px;
}

.section {
  padding: 100px 0;
  position: relative;
}

.section-title-wrap {
  text-align: center;
  max-width: 760px;
  margin: 0 auto 60px;
}

.section-tag {
  display: inline-block;
  padding: 6px 16px;
  background: rgba(0, 240, 255, 0.08);
  border: 1px solid var(--border-cyber);
  border-radius: 50px;
  color: var(--cyan-neon);
  font-size: 0.85rem;
  font-weight: 600;
  letter-spacing: 2px;
  text-transform: uppercase;
  margin-bottom: 16px;
  box-shadow: 0 0 15px rgba(0, 240, 255, 0.15);
}

.section-title {
  font-size: 2.5rem;
  font-weight: 800;
  color: var(--text-bright);
  line-height: 1.25;
  margin-bottom: 16px;
  letter-spacing: -0.5px;
}

.section-title .highlight {
  background: linear-gradient(135deg, var(--cyan-neon), var(--magenta-neon));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.section-desc {
  font-size: 1.1rem;
  color: var(--text-muted);
}

/* 玻璃拟态卡片 */
.cyber-card {
  background: var(--bg-card);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border: 1px solid var(--border-cyber);
  border-radius: var(--radius-md);
  padding: 32px;
  transition: var(--transition);
  position: relative;
  overflow: hidden;
}

.cyber-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 2px;
  background: linear-gradient(90deg, transparent, var(--cyan-neon), transparent);
  opacity: 0;
  transition: var(--transition);
}

.cyber-card:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-glow);
  transform: translateY(-6px);
  box-shadow: 0 12px 40px rgba(0, 240, 255, 0.15);
}

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

/* 按钮规范 */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 14px 32px;
  font-size: 1rem;
  font-weight: 700;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: var(--transition);
  letter-spacing: 0.5px;
  position: relative;
  z-index: 1;
  min-height: 48px; /* 触控适配 */
  white-space: nowrap;
}

.btn-primary {
  background: linear-gradient(135deg, var(--cyan-neon) 0%, #0080ff 100%);
  color: #050b14;
  border: none;
  box-shadow: 0 0 25px var(--cyan-glow);
}

.btn-primary:hover {
  background: linear-gradient(135deg, #33f3ff 0%, #3399ff 100%);
  box-shadow: 0 0 35px rgba(0, 240, 255, 0.7);
  transform: translateY(-2px);
}

.btn-secondary {
  background: rgba(255, 0, 127, 0.1);
  color: var(--magenta-neon);
  border: 1px solid var(--border-magenta);
  box-shadow: 0 0 15px rgba(255, 0, 127, 0.15);
}

.btn-secondary:hover {
  background: rgba(255, 0, 127, 0.25);
  border-color: var(--magenta-neon);
  box-shadow: 0 0 25px var(--magenta-glow);
  transform: translateY(-2px);
  color: #fff;
}

.btn-outline {
  background: transparent;
  color: var(--text-bright);
  border: 1px solid var(--border-cyber);
}

.btn-outline:hover {
  border-color: var(--cyan-neon);
  color: var(--cyan-neon);
  box-shadow: 0 0 20px rgba(0, 240, 255, 0.2);
}

.btn-full {
  width: 100%;
}

/* 3. Header & Navigation */
.header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 1000;
  background: rgba(7, 8, 15, 0.85);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid rgba(0, 240, 255, 0.1);
}

.nav-wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 80px;
}

.brand-logo {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 1.5rem;
  font-weight: 900;
  letter-spacing: 1px;
  color: var(--text-bright);
}

.brand-logo .logo-icon {
  width: 38px;
  height: 38px;
  background: linear-gradient(135deg, var(--cyan-neon), var(--magenta-neon));
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  color: #07080f;
  font-weight: 900;
  font-size: 1.2rem;
  box-shadow: 0 0 15px var(--cyan-glow);
}

.brand-logo span span {
  color: var(--cyan-neon);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 36px;
}

.nav-link {
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--text-muted);
  position: relative;
  padding: 8px 0;
}

.nav-link:hover, .nav-link.active {
  color: var(--cyan-neon);
}

.nav-link::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--cyan-neon);
  transition: var(--transition);
  box-shadow: 0 0 10px var(--cyan-neon);
}

.nav-link:hover::after {
  width: 100%;
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: 16px;
}

/* 4. Hero Section */
.hero-section {
  padding-top: 170px;
  padding-bottom: 100px;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.hero-glow {
  position: absolute;
  top: 30%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 600px;
  height: 600px;
  background: radial-gradient(circle, rgba(0, 240, 255, 0.15) 0%, rgba(139, 92, 246, 0.1) 40%, transparent 70%);
  pointer-events: none;
  z-index: 0;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 8px 20px;
  background: rgba(0, 240, 255, 0.08);
  border: 1px solid var(--border-cyber);
  border-radius: 50px;
  font-size: 0.9rem;
  color: var(--cyan-neon);
  margin-bottom: 28px;
}

.hero-badge .pulse-dot {
  width: 8px;
  height: 8px;
  background-color: var(--cyan-neon);
  border-radius: 50%;
  box-shadow: 0 0 10px var(--cyan-neon);
  animation: pulse 2s infinite;
}

@keyframes pulse {
  0% { transform: scale(0.95); box-shadow: 0 0 0 0 rgba(0, 240, 255, 0.7); }
  70% { transform: scale(1); box-shadow: 0 0 0 10px rgba(0, 240, 255, 0); }
  100% { transform: scale(0.95); box-shadow: 0 0 0 0 rgba(0, 240, 255, 0); }
}

.hero-title {
  font-size: 3.8rem;
  font-weight: 900;
  line-height: 1.15;
  color: var(--text-bright);
  max-width: 950px;
  margin: 0 auto 24px;
  letter-spacing: -1px;
}

.hero-title .gradient-text {
  background: linear-gradient(135deg, #ffffff 0%, var(--cyan-neon) 50%, var(--magenta-neon) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-subtitle {
  font-size: 1.25rem;
  color: var(--text-muted);
  max-width: 720px;
  margin: 0 auto 40px;
  line-height: 1.6;
}

.hero-cta-group {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 20px;
  margin-bottom: 60px;
}

.hero-stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  max-width: 1000px;
  margin: 0 auto;
}

.stat-card {
  background: rgba(13, 16, 29, 0.6);
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: var(--radius-md);
  padding: 24px 16px;
  backdrop-filter: blur(10px);
}

.stat-num {
  font-size: 2.2rem;
  font-weight: 900;
  color: var(--cyan-neon);
  font-family: monospace, var(--font-main);
  text-shadow: 0 0 15px rgba(0, 240, 255, 0.4);
}

.stat-label {
  font-size: 0.88rem;
  color: var(--text-muted);
  margin-top: 4px;
}

/* 5. 核心优势 (Features) */
.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
}

.feature-icon {
  width: 56px;
  height: 56px;
  background: rgba(0, 240, 255, 0.1);
  border: 1px solid var(--border-cyber);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.6rem;
  margin-bottom: 20px;
  color: var(--cyan-neon);
  box-shadow: 0 0 20px rgba(0, 240, 255, 0.1);
}

.feature-title {
  font-size: 1.3rem;
  font-weight: 700;
  color: var(--text-bright);
  margin-bottom: 12px;
}

.feature-desc {
  font-size: 0.95rem;
  color: var(--text-muted);
  line-height: 1.6;
}

/* 6. 流媒体与 AI 支持 (Ecosystem) */
.eco-box {
  background: linear-gradient(135deg, rgba(13, 16, 29, 0.9) 0%, rgba(20, 25, 45, 0.8) 100%);
  border: 1px solid var(--border-cyber);
  border-radius: var(--radius-lg);
  padding: 48px;
  box-shadow: 0 20px 60px rgba(0, 0, 0, 0.5);
}

.eco-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 40px;
}

.eco-column-title {
  font-size: 1.4rem;
  font-weight: 800;
  color: var(--text-bright);
  margin-bottom: 24px;
  display: flex;
  align-items: center;
  gap: 12px;
}

.eco-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.eco-tag {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 10px 18px;
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: 50px;
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--text-main);
  transition: var(--transition);
}

.eco-tag:hover {
  background: rgba(0, 240, 255, 0.12);
  border-color: var(--cyan-neon);
  color: var(--cyan-neon);
  box-shadow: 0 0 15px rgba(0, 240, 255, 0.2);
}

.eco-badge {
  font-size: 0.75rem;
  padding: 2px 8px;
  background: var(--magenta-neon);
  color: #fff;
  border-radius: 10px;
  font-weight: 700;
}

/* 7. 套餐价格 (Pricing) */
.pricing-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  align-items: stretch;
}

.pricing-card {
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.pricing-card.popular {
  border-color: var(--magenta-neon);
  box-shadow: 0 0 35px rgba(255, 0, 127, 0.25);
  transform: scale(1.04);
}

.pricing-card.popular::after {
  content: "最受欢迎 / POPULAR";
  position: absolute;
  top: 16px;
  right: -32px;
  background: var(--magenta-neon);
  color: #fff;
  font-size: 0.7rem;
  font-weight: 800;
  padding: 4px 36px;
  transform: rotate(45deg);
  box-shadow: 0 2px 10px rgba(255, 0, 127, 0.4);
}

.plan-name {
  font-size: 1.3rem;
  font-weight: 800;
  color: var(--text-bright);
  margin-bottom: 8px;
}

.plan-desc {
  font-size: 0.88rem;
  color: var(--text-muted);
  margin-bottom: 24px;
  min-height: 40px;
}

.plan-price {
  font-size: 2.5rem;
  font-weight: 900;
  color: var(--cyan-neon);
  font-family: monospace, var(--font-main);
  margin-bottom: 24px;
  display: flex;
  align-items: baseline;
  gap: 4px;
}

.plan-price span.unit {
  font-size: 1rem;
  color: var(--text-muted);
  font-weight: 400;
}

.plan-features {
  margin-bottom: 32px;
  flex-grow: 1;
}

.plan-features li {
  font-size: 0.9rem;
  color: var(--text-main);
  margin-bottom: 12px;
  display: flex;
  align-items: center;
  gap: 10px;
}

.plan-features li .check {
  color: var(--cyan-neon);
  font-weight: bold;
}

/* 8. 用户评价 (Testimonials) */
.reviews-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
}

.review-user {
  display: flex;
  align-items: center;
  gap: 16px;
  margin-bottom: 16px;
}

.user-avatar {
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--cyan-neon), var(--purple-neon));
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 800;
  color: #07080f;
  font-size: 1.1rem;
}

.user-name {
  font-size: 1rem;
  font-weight: 700;
  color: var(--text-bright);
}

.user-role {
  font-size: 0.82rem;
  color: var(--text-muted);
}

.review-stars {
  color: #ffb703;
  margin-bottom: 12px;
  font-size: 0.9rem;
}

.review-text {
  font-size: 0.95rem;
  color: var(--text-main);
  line-height: 1.6;
}

/* 9. FAQ Section */
.faq-wrap {
  max-width: 860px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.faq-item {
  background: var(--bg-card);
  border: 1px solid var(--border-cyber);
  border-radius: var(--radius-md);
  padding: 24px 32px;
}

.faq-question {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--text-bright);
  margin-bottom: 10px;
  display: flex;
  align-items: center;
  gap: 12px;
}

.faq-question::before {
  content: "Q";
  color: var(--cyan-neon);
  font-weight: 900;
  font-size: 1.2rem;
}

.faq-answer {
  font-size: 0.98rem;
  color: var(--text-muted);
  line-height: 1.7;
  padding-left: 28px;
}

/* 10. 页脚 (Footer) - 严格遵循用户要求只保留 4 个标题链接 */
.footer {
  background: rgba(5, 6, 12, 0.95);
  border-top: 1px solid rgba(0, 240, 255, 0.15);
  padding: 60px 0 40px;
  margin-top: auto;
}

.footer-inner {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 32px;
  text-align: center;
}

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

.footer-link {
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--text-main);
  padding: 8px 16px;
  border-radius: var(--radius-sm);
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid rgba(255, 255, 255, 0.08);
  transition: var(--transition);
}

.footer-link:hover {
  color: var(--cyan-neon);
  border-color: var(--cyan-neon);
  background: rgba(0, 240, 255, 0.1);
  box-shadow: 0 0 15px rgba(0, 240, 255, 0.2);
}

.footer-copyright {
  font-size: 0.85rem;
  color: var(--text-dim);
}

/* 11. 子页面通用样式 */
.subpage-hero {
  padding-top: 160px;
  padding-bottom: 60px;
  text-align: center;
}

.subpage-content {
  padding-bottom: 100px;
}

.article-card {
  background: var(--bg-card);
  border: 1px solid var(--border-cyber);
  border-radius: var(--radius-lg);
  padding: 48px;
  max-width: 900px;
  margin: 0 auto;
}

.article-section {
  margin-bottom: 40px;
}

.article-section:last-child {
  margin-bottom: 0;
}

.article-h2 {
  font-size: 1.5rem;
  font-weight: 800;
  color: var(--cyan-neon);
  margin-bottom: 16px;
  border-bottom: 1px solid rgba(0, 240, 255, 0.15);
  padding-bottom: 10px;
}

.article-p {
  font-size: 1rem;
  color: var(--text-main);
  line-height: 1.8;
  margin-bottom: 16px;
}

.article-ul {
  padding-left: 20px;
  margin-bottom: 16px;
}

.article-ul li {
  font-size: 0.98rem;
  color: var(--text-muted);
  margin-bottom: 8px;
  list-style-type: disc;
}

/* 12. 响应式适配 (@media Queries) */
@media (max-width: 1024px) {
  .hero-title {
    font-size: 3rem;
  }
  .features-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .pricing-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .pricing-card.popular {
    transform: none;
  }
  .eco-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 768px) {
  .header {
    padding: 0 10px;
  }
  .nav-wrap {
    height: 70px;
  }
  .nav-links {
    display: none; /* 移动端隐藏主导航链接，聚焦于 CTA */
  }
  .hero-section {
    padding-top: 120px;
    padding-bottom: 60px;
  }
  .hero-title {
    font-size: 2.2rem;
  }
  .hero-subtitle {
    font-size: 1rem;
  }
  .hero-cta-group {
    flex-direction: column;
    width: 100%;
  }
  .hero-cta-group .btn {
    width: 100%;
  }
  .hero-stats {
    grid-template-columns: repeat(2, 1fr);
    gap: 12px;
  }
  .features-grid {
    grid-template-columns: 1fr;
  }
  .pricing-grid {
    grid-template-columns: 1fr;
  }
  .reviews-grid {
    grid-template-columns: 1fr;
  }
  .footer-nav {
    flex-direction: column;
    gap: 16px;
    width: 100%;
  }
  .footer-link {
    width: 100%;
    text-align: center;
  }
  .article-card {
    padding: 24px;
  }
}

@media (max-width: 480px) {
  .section-title {
    font-size: 1.8rem;
  }
  .stat-num {
    font-size: 1.8rem;
  }
  .eco-box {
    padding: 24px;
  }
}