/* Modern Twilight Dark Theme CSS for 白月光官网 (bygjc.cyou) */
:root {
  --bg-dark: #090d16;
  --bg-card: #111827;
  --bg-card-hover: #1f293d;
  --primary: #8a2be2;
  --primary-glow: rgba(138, 43, 226, 0.4);
  --accent: #00e5ff;
  --accent-glow: rgba(0, 229, 255, 0.3);
  --text-main: #f3f4f6;
  --text-muted: #9ca3af;
  --text-dim: #6b7280;
  --border-color: rgba(255, 255, 255, 0.08);
  --border-glow: rgba(138, 43, 226, 0.3);
  --radius: 12px;
  --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --max-width: 1200px;
}

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

html {
  scroll-behavior: smooth;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  background-color: var(--bg-dark);
  color: var(--text-main);
  line-height: 1.6;
}

body {
  overflow-x: hidden;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

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

a:hover {
  color: #66efff;
}

/* Header & Nav */
header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: rgba(9, 13, 22, 0.85);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-color);
}

.header-container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0.8rem 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.brand {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  font-size: 1.25rem;
  font-weight: 700;
  color: #fff;
}

.brand img {
  width: 38px;
  height: 38px;
  border-radius: 50%;
  box-shadow: 0 0 10px var(--primary-glow);
}

.brand-text span {
  color: var(--accent);
}

nav {
  display: flex;
  align-items: center;
  gap: 1.8rem;
}

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

.nav-links a {
  color: var(--text-muted);
  font-size: 0.95rem;
  font-weight: 500;
}

.nav-links a:hover {
  color: #fff;
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 0.8rem;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.6rem 1.2rem;
  border-radius: 8px;
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
  border: none;
}

.btn-primary {
  background: linear-gradient(135deg, var(--primary), #6366f1);
  color: #fff;
  box-shadow: 0 4px 15px var(--primary-glow);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(138, 43, 226, 0.6);
  color: #fff;
}

.btn-accent {
  background: linear-gradient(135deg, #00b4db, #0083b0);
  color: #fff;
  box-shadow: 0 4px 15px var(--accent-glow);
}

.btn-accent:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(0, 229, 255, 0.5);
  color: #fff;
}

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

.btn-outline:hover {
  background: rgba(255, 255, 255, 0.1);
  border-color: var(--accent);
  color: #fff;
}

.nav-toggle {
  display: none;
  background: none;
  border: none;
  color: #fff;
  font-size: 1.5rem;
  cursor: pointer;
}

/* Hero Section */
.hero {
  padding: 4rem 1.5rem 5rem;
  text-align: center;
  position: relative;
  background: radial-gradient(circle at 50% 20%, rgba(138, 43, 226, 0.15) 0%, transparent 60%);
}

.hero-content {
  max-width: 850px;
  margin: 0 auto;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.35rem 1rem;
  background: rgba(138, 43, 226, 0.15);
  border: 1px solid rgba(138, 43, 226, 0.3);
  border-radius: 50px;
  color: var(--accent);
  font-size: 0.85rem;
  font-weight: 600;
  margin-bottom: 1.5rem;
}

.hero h1 {
  font-size: 2.8rem;
  font-weight: 800;
  line-height: 1.25;
  margin-bottom: 1.2rem;
  background: linear-gradient(135deg, #ffffff 30%, var(--accent) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero p {
  font-size: 1.15rem;
  color: var(--text-muted);
  margin-bottom: 2rem;
  max-width: 720px;
  margin-left: auto;
  margin-right: auto;
}

.hero-cta {
  display: flex;
  justify-content: center;
  gap: 1rem;
  flex-wrap: wrap;
}

.kw-tags {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 0.6rem;
  margin-top: 2.5rem;
}

.kw-tag {
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid var(--border-color);
  padding: 0.3rem 0.8rem;
  border-radius: 6px;
  font-size: 0.82rem;
  color: var(--text-muted);
}

/* Sections */
.section {
  padding: 4rem 1.5rem;
  max-width: var(--max-width);
  margin: 0 auto;
  width: 100%;
}

.section-title {
  text-align: center;
  margin-bottom: 3rem;
}

.section-title h2 {
  font-size: 2rem;
  font-weight: 700;
  margin-bottom: 0.5rem;
  color: #fff;
}

.section-title p {
  color: var(--text-muted);
  font-size: 1rem;
}

/* Features Grid */
.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 1.5rem;
}

.feature-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius);
  padding: 1.8rem;
  transition: var(--transition);
}

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

.feature-icon {
  width: 48px;
  height: 48px;
  border-radius: 10px;
  background: rgba(138, 43, 226, 0.15);
  color: var(--accent);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  margin-bottom: 1.2rem;
}

.feature-card h3 {
  font-size: 1.2rem;
  margin-bottom: 0.6rem;
  color: #fff;
}

.feature-card p {
  color: var(--text-muted);
  font-size: 0.92rem;
}

/* Pricing Grid */
.pricing-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(270px, 1fr));
  gap: 1.5rem;
}

.pricing-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius);
  padding: 2rem 1.5rem;
  position: relative;
  display: flex;
  flex-direction: column;
  transition: var(--transition);
}

.pricing-card.featured {
  border-color: var(--primary);
  box-shadow: 0 0 25px var(--primary-glow);
  background: linear-gradient(180deg, rgba(138, 43, 226, 0.1) 0%, var(--bg-card) 100%);
}

.badge-pop {
  position: absolute;
  top: -12px;
  right: 20px;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  color: #fff;
  font-size: 0.75rem;
  font-weight: 700;
  padding: 0.2rem 0.8rem;
  border-radius: 20px;
  text-transform: uppercase;
}

.pricing-header h3 {
  font-size: 1.3rem;
  color: #fff;
  margin-bottom: 0.5rem;
}

.pricing-price {
  font-size: 2.2rem;
  font-weight: 800;
  color: var(--accent);
  margin: 1rem 0 0.5rem;
}

.pricing-price span {
  font-size: 0.9rem;
  color: var(--text-muted);
  font-weight: 400;
}

.pricing-desc {
  color: var(--text-muted);
  font-size: 0.88rem;
  margin-bottom: 1.5rem;
}

.pricing-features {
  list-style: none;
  margin-bottom: 2rem;
  flex-grow: 1;
}

.pricing-features li {
  padding: 0.5rem 0;
  border-bottom: 1px solid rgba(255, 255, 255, 0.04);
  color: var(--text-main);
  font-size: 0.9rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

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

/* Articles Section */
.articles-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 1.5rem;
}

.article-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius);
  overflow: hidden;
  display: flex;
  flex-direction: column;
  transition: var(--transition);
}

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

.article-body {
  padding: 1.5rem;
  display: flex;
  flex-direction: column;
  flex-grow: 1;
}

.article-meta {
  font-size: 0.8rem;
  color: var(--accent);
  margin-bottom: 0.6rem;
}

.article-card h3 {
  font-size: 1.15rem;
  margin-bottom: 0.8rem;
  line-height: 1.4;
}

.article-card h3 a {
  color: #fff;
}

.article-card h3 a:hover {
  color: var(--accent);
}

.article-card p {
  color: var(--text-muted);
  font-size: 0.9rem;
  margin-bottom: 1.2rem;
  flex-grow: 1;
}

/* Testimonials */
.testimonials-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.5rem;
}

.testimonial-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius);
  padding: 1.5rem;
}

.user-info {
  display: flex;
  align-items: center;
  gap: 0.8rem;
  margin-bottom: 1rem;
}

.user-avatar {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: bold;
  color: #fff;
}

.user-name {
  font-weight: 600;
  color: #fff;
}

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

.stars {
  color: #f59e0b;
  margin-bottom: 0.5rem;
}

/* FAQ */
.faq-list {
  max-width: 800px;
  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);
  overflow: hidden;
}

.faq-question {
  padding: 1.2rem 1.5rem;
  font-weight: 600;
  color: #fff;
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  user-select: none;
}

.faq-question::after {
  content: "+";
  font-size: 1.4rem;
  color: var(--accent);
  transition: transform 0.3s;
}

.faq-item.active .faq-question::after {
  content: "−";
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s ease-out, padding 0.3s ease;
  padding: 0 1.5rem;
  color: var(--text-muted);
  font-size: 0.93rem;
}

.faq-item.active .faq-answer {
  padding: 0 1.5rem 1.2rem;
  max-height: 300px;
}

/* Article Page Layout */
.article-page-container {
  max-width: 900px;
  margin: 2rem auto;
  padding: 0 1.5rem;
}

.breadcrumb {
  margin-bottom: 1.5rem;
  font-size: 0.88rem;
  color: var(--text-muted);
}

.article-header {
  margin-bottom: 2.5rem;
  border-bottom: 1px solid var(--border-color);
  padding-bottom: 1.5rem;
}

.article-header h1 {
  font-size: 2.2rem;
  line-height: 1.3;
  margin-bottom: 1rem;
  color: #fff;
}

.article-content {
  font-size: 1.05rem;
  line-height: 1.8;
  color: var(--text-main);
}

.article-content h2 {
  font-size: 1.6rem;
  margin: 2rem 0 1rem;
  color: #fff;
  border-left: 4px solid var(--primary);
  padding-left: 0.8rem;
}

.article-content h3 {
  font-size: 1.25rem;
  margin: 1.5rem 0 0.8rem;
  color: var(--accent);
}

.article-content p {
  margin-bottom: 1.2rem;
  color: #d1d5db;
}

.article-content ul, .article-content ol {
  margin: 1rem 0 1.5rem 1.5rem;
  color: #d1d5db;
}

.article-content li {
  margin-bottom: 0.5rem;
}

.callout-box {
  background: rgba(138, 43, 226, 0.1);
  border: 1px solid var(--border-glow);
  border-radius: 8px;
  padding: 1.2rem 1.5rem;
  margin: 1.5rem 0;
}

.internal-nav-box {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius);
  padding: 1.5rem;
  margin: 3rem 0;
}

.internal-nav-box h4 {
  color: var(--accent);
  margin-bottom: 1rem;
}

.internal-nav-box ul {
  list-style: none;
  margin: 0;
}

.internal-nav-box li {
  margin-bottom: 0.6rem;
}

/* Footer & PBN Links */
footer {
  background: #05080e;
  border-top: 1px solid var(--border-color);
  padding: 3rem 1.5rem 2rem;
  margin-top: auto;
  text-align: center;
}

.footer-container {
  max-width: var(--max-width);
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1.5rem;
}

.footer-nav {
  display: flex;
  gap: 1.5rem;
  flex-wrap: wrap;
  justify-content: center;
}

.footer-nav a {
  color: var(--text-muted);
  font-size: 0.9rem;
}

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

/* PBN Friendly Link Area */
.friend-links-area {
  margin-top: 1rem;
  padding-top: 1rem;
  border-top: 1px solid rgba(255, 255, 255, 0.05);
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 1rem;
  flex-wrap: wrap;
  font-size: 0.8rem;
  color: var(--text-dim);
}

.friend-links-area span {
  color: var(--text-dim);
}

.friend-links-area a {
  color: var(--text-dim);
  text-decoration: none;
  font-size: 0.8rem;
  opacity: 0.85;
  transition: opacity 0.2s ease, color 0.2s ease;
}

.friend-links-area a:hover {
  color: var(--accent);
  opacity: 1;
}

/* Responsive */
@media (max-width: 768px) {
  .nav-links, .header-actions {
    display: none;
  }

  .nav-toggle {
    display: block;
  }

  .hero h1 {
    font-size: 2rem;
  }

  .mobile-menu {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: 100%;
    left: 0;
    width: 100%;
    background: var(--bg-card);
    border-bottom: 1px solid var(--border-color);
    padding: 1.5rem;
    gap: 1rem;
  }

  .mobile-menu .nav-links {
    display: flex;
    flex-direction: column;
  }

  .mobile-menu .header-actions {
    display: flex;
    flex-direction: column;
  }
}