/* 瞬云 SHUNYUN - 极夜青光视觉样式表 */
:root {
  --bg-color: #06070a;
  --bg-card: rgba(18, 20, 28, 0.7);
  --bg-card-hover: rgba(26, 30, 42, 0.85);
  --border-color: rgba(255, 255, 255, 0.08);
  --border-glow: rgba(0, 245, 212, 0.3);
  --text-main: #f1f5f9;
  --text-sub: #94a3b8;
  --text-muted: #64748b;
  --accent-cyan: #00f5d4;
  --accent-cyan-glow: rgba(0, 245, 212, 0.15);
  --accent-blue: #38bdf8;
  --radius-lg: 20px;
  --radius-md: 12px;
  --font-family: -apple-system, BlinkMacSystemFont, "SF Pro Display", "PingFang SC", "Microsoft YaHei", sans-serif;
  --transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
}

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

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

body {
  overflow-x: hidden;
  background: radial-gradient(circle at 50% 0%, rgba(0, 245, 212, 0.05) 0%, transparent 60%),
              radial-gradient(circle at 100% 50%, rgba(56, 189, 248, 0.03) 0%, transparent 50%),
              var(--bg-color);
  min-height: 100vh;
}

a {
  color: inherit;
  text-decoration: none;
}

.container {
  width: 100%;
  max-width: 1240px;
  margin: 0 auto;
  padding: 0 24px;
}

/* Header & Nav */
header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  background: rgba(6, 7, 10, 0.75);
  border-bottom: 1px solid rgba(255, 255, 255, 0.05);
  transition: var(--transition);
}

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

.brand-logo {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 1.15rem;
  font-weight: 500;
  letter-spacing: 2px;
  color: var(--text-main);
}

.brand-logo img {
  width: 38px;
  height: 38px;
  object-fit: contain;
  filter: drop-shadow(0 0 10px rgba(0, 245, 212, 0.7));
}

.brand-logo span.en {
  font-size: 0.85rem;
  color: var(--text-sub);
  letter-spacing: 4px;
  font-weight: 300;
}

.nav-links {
  display: flex;
  gap: 36px;
  align-items: center;
  list-style: none;
}

.nav-links a {
  font-size: 0.95rem;
  color: var(--text-sub);
  transition: var(--transition);
  position: relative;
  font-weight: 300;
}

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

.nav-links a.btn-nav {
  padding: 8px 20px;
  border-radius: 30px;
  border: 1px solid rgba(0, 245, 212, 0.4);
  color: var(--accent-cyan);
  background: rgba(0, 245, 212, 0.05);
  font-weight: 400;
}

.nav-links a.btn-nav:hover {
  background: var(--accent-cyan);
  color: #06070a;
  box-shadow: 0 0 20px rgba(0, 245, 212, 0.4);
}

/* Mobile Nav Toggle */
.menu-toggle {
  display: none;
  background: none;
  border: none;
  color: var(--text-main);
  font-size: 1.5rem;
  cursor: pointer;
}

/* Hero Section */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  padding-top: 100px;
  padding-bottom: 60px;
  position: relative;
  overflow: hidden;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 40px;
  align-items: center;
}

.hero-content {
  max-width: 600px;
}

.hero-title {
  font-size: 3.6rem;
  font-weight: 300;
  line-height: 1.25;
  letter-spacing: -1px;
  margin-bottom: 24px;
  color: #ffffff;
}

.hero-title span {
  display: block;
}

.hero-desc {
  font-size: 1.05rem;
  color: var(--text-sub);
  margin-bottom: 40px;
  line-height: 1.8;
  font-weight: 300;
}

.hero-desc strong {
  color: var(--accent-cyan);
  font-weight: 400;
}

.hero-btns {
  display: flex;
  gap: 16px;
  align-items: center;
  flex-wrap: wrap;
}

.btn-primary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 14px 36px;
  border-radius: 40px;
  border: 1px solid var(--accent-cyan);
  background: rgba(0, 245, 212, 0.08);
  color: var(--accent-cyan);
  font-size: 0.95rem;
  letter-spacing: 1px;
  transition: var(--transition);
  cursor: pointer;
  box-shadow: 0 0 15px rgba(0, 245, 212, 0.15);
}

.btn-primary:hover {
  background: var(--accent-cyan);
  color: #06070a;
  box-shadow: 0 0 30px rgba(0, 245, 212, 0.4);
  transform: translateY(-2px);
}

.btn-secondary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 14px 36px;
  border-radius: 40px;
  border: 1px solid rgba(255, 255, 255, 0.15);
  background: rgba(255, 255, 255, 0.02);
  color: var(--text-sub);
  font-size: 0.95rem;
  transition: var(--transition);
  cursor: pointer;
}

.btn-secondary:hover {
  border-color: rgba(255, 255, 255, 0.4);
  color: var(--text-main);
  background: rgba(255, 255, 255, 0.06);
  transform: translateY(-2px);
}

/* Hero Concentric Rings Visual */
.hero-visual {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  height: 480px;
}

.ring-container {
  position: relative;
  width: 420px;
  height: 420px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.ring {
  position: absolute;
  border-radius: 50%;
  border: 1px solid rgba(0, 245, 212, 0.12);
  transition: var(--transition);
}

.ring-1 {
  width: 420px;
  height: 420px;
  border-color: rgba(0, 245, 212, 0.08);
  animation: pulseRing 10s infinite ease-in-out;
}

.ring-2 {
  width: 300px;
  height: 300px;
  border-color: rgba(0, 245, 212, 0.18);
  animation: rotateRing 20s linear infinite;
}

.ring-3 {
  width: 180px;
  height: 180px;
  border-color: rgba(0, 245, 212, 0.28);
  animation: pulseRing 6s infinite ease-in-out reverse;
}

.core-dot {
  width: 12px;
  height: 12px;
  background-color: var(--accent-cyan);
  border-radius: 50%;
  box-shadow: 0 0 25px 6px rgba(0, 245, 212, 0.8);
  animation: glowPulse 2.5s infinite ease-in-out;
}

@keyframes pulseRing {
  0%, 100% { transform: scale(1); opacity: 0.5; }
  50% { transform: scale(1.05); opacity: 0.9; }
}

@keyframes rotateRing {
  from { transform: rotate(0deg); }
  to { transform: rotate(360deg); }
}

@keyframes glowPulse {
  0%, 100% { transform: scale(1); box-shadow: 0 0 20px 4px rgba(0, 245, 212, 0.7); }
  50% { transform: scale(1.3); box-shadow: 0 0 35px 10px rgba(0, 245, 212, 0.9); }
}

/* Section Common Styles */
.section {
  padding: 100px 0;
  position: relative;
}

.section-header {
  text-align: center;
  max-width: 680px;
  margin: 0 auto 60px auto;
}

.section-tag {
  font-size: 0.85rem;
  letter-spacing: 3px;
  color: var(--accent-cyan);
  text-transform: uppercase;
  margin-bottom: 12px;
  font-weight: 500;
}

.section-title {
  font-size: 2.4rem;
  font-weight: 300;
  letter-spacing: -0.5px;
  margin-bottom: 16px;
  color: var(--text-main);
}

.section-desc {
  font-size: 1rem;
  color: var(--text-sub);
  font-weight: 300;
}

/* Feature Cards */
.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 28px;
}

.feature-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 36px 28px;
  transition: var(--transition);
  backdrop-filter: blur(10px);
  position: relative;
  overflow: hidden;
}

.feature-card:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-glow);
  transform: translateY(-6px);
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.4), 0 0 30px rgba(0, 245, 212, 0.08);
}

.feature-icon {
  width: 52px;
  height: 52px;
  border-radius: 14px;
  background: rgba(0, 245, 212, 0.08);
  border: 1px solid rgba(0, 245, 212, 0.2);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.4rem;
  color: var(--accent-cyan);
  margin-bottom: 24px;
}

.feature-card h3 {
  font-size: 1.3rem;
  font-weight: 400;
  margin-bottom: 12px;
  color: var(--text-main);
}

.feature-card p {
  font-size: 0.95rem;
  color: var(--text-sub);
  font-weight: 300;
  line-height: 1.7;
}

/* Pricing Section */
.pricing-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 28px;
}

.price-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 36px 28px;
  transition: var(--transition);
  display: flex;
  flex-direction: column;
  position: relative;
}

.price-card.popular {
  border-color: var(--accent-cyan);
  background: rgba(0, 245, 212, 0.04);
  box-shadow: 0 0 30px rgba(0, 245, 212, 0.12);
}

.badge-popular {
  position: absolute;
  top: -12px;
  right: 24px;
  background: var(--accent-cyan);
  color: #06070a;
  font-size: 0.75rem;
  font-weight: 600;
  padding: 4px 14px;
  border-radius: 20px;
  letter-spacing: 1px;
}

.price-header h3 {
  font-size: 1.3rem;
  font-weight: 400;
  margin-bottom: 8px;
}

.price-amount {
  display: flex;
  align-items: baseline;
  margin: 20px 0;
}

.price-currency {
  font-size: 1.4rem;
  color: var(--accent-cyan);
  margin-right: 4px;
}

.price-val {
  font-size: 3rem;
  font-weight: 300;
  color: #ffffff;
  line-height: 1;
}

.price-unit {
  font-size: 0.9rem;
  color: var(--text-sub);
  margin-left: 6px;
}

.price-features {
  list-style: none;
  margin: 24px 0 36px 0;
  flex-grow: 1;
}

.price-features li {
  font-size: 0.92rem;
  color: var(--text-sub);
  margin-bottom: 12px;
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 300;
}

.price-features li::before {
  content: "✓";
  color: var(--accent-cyan);
  font-weight: bold;
}

.price-btn {
  width: 100%;
}

/* Articles Navigation Section */
.articles-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(340px, 1fr));
  gap: 28px;
}

.article-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 28px;
  transition: var(--transition);
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.article-card:hover {
  border-color: var(--border-glow);
  transform: translateY(-4px);
  background: var(--bg-card-hover);
}

.article-tag {
  display: inline-block;
  font-size: 0.8rem;
  color: var(--accent-cyan);
  background: rgba(0, 245, 212, 0.08);
  padding: 4px 12px;
  border-radius: 20px;
  margin-bottom: 16px;
  width: fit-content;
}

.article-card h3 {
  font-size: 1.15rem;
  font-weight: 400;
  line-height: 1.5;
  margin-bottom: 12px;
  color: var(--text-main);
}

.article-card p {
  font-size: 0.9rem;
  color: var(--text-sub);
  line-height: 1.6;
  margin-bottom: 20px;
  font-weight: 300;
}

.article-link {
  font-size: 0.9rem;
  color: var(--accent-cyan);
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-weight: 400;
  transition: var(--transition);
}

.article-link:hover {
  gap: 10px;
}

/* User Reviews Section */
.reviews-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 24px;
}

.review-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 28px;
  transition: var(--transition);
}

.review-card:hover {
  border-color: rgba(255, 255, 255, 0.15);
}

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

.user-avatar {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: linear-gradient(135deg, rgba(0, 245, 212, 0.2), rgba(56, 189, 248, 0.2));
  border: 1px solid var(--accent-cyan);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 600;
  color: var(--accent-cyan);
  font-size: 1.1rem;
}

.user-info h4 {
  font-size: 1rem;
  font-weight: 400;
}

.user-info span {
  font-size: 0.8rem;
  color: var(--text-muted);
}

.review-rating {
  color: #f59e0b;
  margin-bottom: 12px;
  font-size: 0.9rem;
}

.review-text {
  font-size: 0.92rem;
  color: var(--text-sub);
  line-height: 1.7;
  font-weight: 300;
}

/* FAQ Accordion */
.faq-container {
  max-width: 800px;
  margin: 0 auto;
}

.faq-item {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  margin-bottom: 16px;
  overflow: hidden;
  transition: var(--transition);
}

.faq-question {
  padding: 22px 28px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  cursor: pointer;
  font-size: 1.05rem;
  font-weight: 400;
  color: var(--text-main);
  user-select: none;
}

.faq-icon {
  font-size: 1.2rem;
  transition: transform 0.3s ease;
  color: var(--accent-cyan);
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.35s cubic-bezier(0.16, 1, 0.3, 1), padding 0.35s ease;
  padding: 0 28px;
  color: var(--text-sub);
  font-size: 0.95rem;
  line-height: 1.7;
  font-weight: 300;
}

.faq-item.active {
  border-color: var(--border-glow);
  background: var(--bg-card-hover);
}

.faq-item.active .faq-icon {
  transform: rotate(45deg);
}

.faq-item.active .faq-answer {
  max-height: 300px;
  padding: 0 28px 22px 28px;
}

/* Footer & PBN Links Area (核心任务2规范) */
footer {
  background: #040507;
  border-top: 1px solid rgba(255, 255, 255, 0.05);
  padding: 60px 0 40px 0;
  text-align: center;
}

.footer-content {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 24px;
}

.footer-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 1.1rem;
  letter-spacing: 2px;
}

.footer-brand img {
  width: 24px;
  height: 24px;
}

.footer-links {
  display: flex;
  gap: 24px;
  list-style: none;
  font-size: 0.9rem;
  color: var(--text-sub);
  flex-wrap: wrap;
  justify-content: center;
}

.footer-links a:hover {
  color: var(--accent-cyan);
}

/* PBN友情链接专区 (低调、小字号、高契合、必须dofollow + target="_blank") */
.friend-links-area {
  margin-top: 16px;
  padding-top: 20px;
  border-top: 1px solid rgba(255, 255, 255, 0.03);
  font-size: 0.82rem;
  color: var(--text-muted);
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  flex-wrap: wrap;
}

.friend-links-area span.label {
  color: #475569;
}

.friend-links-area a {
  color: #64748b;
  text-decoration: none;
  transition: color 0.2s ease;
}

.friend-links-area a:hover {
  color: var(--accent-cyan);
}

.copyright {
  font-size: 0.85rem;
  color: #475569;
  margin-top: 10px;
}

/* Single Article Layout */
.article-page {
  padding-top: 120px;
  padding-bottom: 80px;
}

.breadcrumb {
  display: flex;
  gap: 10px;
  font-size: 0.88rem;
  color: var(--text-muted);
  margin-bottom: 30px;
}

.breadcrumb a:hover {
  color: var(--accent-cyan);
}

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

.article-title-main {
  font-size: 2.5rem;
  font-weight: 400;
  line-height: 1.3;
  margin-bottom: 16px;
  color: #ffffff;
}

.article-meta {
  display: flex;
  gap: 20px;
  font-size: 0.88rem;
  color: var(--text-sub);
}

.article-body {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 40px;
  font-size: 1.02rem;
  line-height: 1.9;
  color: var(--text-sub);
}

.article-body h2 {
  font-size: 1.6rem;
  color: var(--text-main);
  margin: 36px 0 16px 0;
  font-weight: 400;
  border-left: 3px solid var(--accent-cyan);
  padding-left: 12px;
}

.article-body h3 {
  font-size: 1.25rem;
  color: var(--text-main);
  margin: 28px 0 12px 0;
  font-weight: 400;
}

.article-body p {
  margin-bottom: 20px;
}

.article-body ul, .article-body ol {
  margin: 0 0 24px 24px;
}

.article-body li {
  margin-bottom: 8px;
}

.article-cta {
  margin: 40px 0;
  padding: 30px;
  background: rgba(0, 245, 212, 0.05);
  border: 1px solid rgba(0, 245, 212, 0.2);
  border-radius: var(--radius-md);
  text-align: center;
}

.article-cta h4 {
  font-size: 1.3rem;
  color: var(--text-main);
  margin-bottom: 10px;
}

.article-nav-links {
  display: flex;
  justify-content: space-between;
  margin-top: 40px;
  padding-top: 24px;
  border-top: 1px solid var(--border-color);
}

/* Responsive Rules */
@media (max-width: 992px) {
  .hero-grid {
    grid-template-columns: 1fr;
    text-align: center;
  }
  .hero-content {
    margin: 0 auto;
  }
  .hero-btns {
    justify-content: center;
  }
  .hero-title {
    font-size: 2.8rem;
  }
  .hero-visual {
    height: 340px;
  }
  .ring-container {
    transform: scale(0.8);
  }
}

@media (max-width: 768px) {
  .nav-links {
    display: none;
    position: absolute;
    top: 80px;
    left: 0;
    right: 0;
    background: #06070a;
    flex-direction: column;
    padding: 24px;
    border-bottom: 1px solid var(--border-color);
  }
  .nav-links.active {
    display: flex;
  }
  .menu-toggle {
    display: block;
  }
  .hero-title {
    font-size: 2.2rem;
  }
  .article-body {
    padding: 24px;
  }
}