/* XSUS.click - Main Theme & Style System */

:root {
  --bg-dark: #070a14;
  --bg-card: rgba(15, 23, 42, 0.75);
  --bg-card-hover: rgba(30, 41, 59, 0.85);
  --bg-glass: rgba(15, 23, 42, 0.65);
  
  --primary-cyan: #00f2fe;
  --primary-blue: #4facfe;
  --accent-purple: #9d4edd;
  --accent-pink: #f72585;
  
  --text-main: #f8fafc;
  --text-muted: #94a3b8;
  --text-sub: #cbd5e1;
  
  --border-color: rgba(255, 255, 255, 0.1);
  --border-glow: rgba(0, 242, 254, 0.3);
  
  --shadow-glow: 0 0 25px rgba(0, 242, 254, 0.15);
  --shadow-purple: 0 0 25px rgba(157, 78, 221, 0.25);

  --font-family: 'Inter', system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
  --max-width: 1240px;
}

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

body {
  background-color: var(--bg-dark);
  color: var(--text-main);
  font-family: var(--font-family);
  line-height: 1.6;
  overflow-x: hidden;
  position: relative;
}

/* Background Glowing Elements */
#canvas-particles {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  z-index: -1;
  pointer-events: none;
}

.glow-bg-1 {
  position: absolute;
  top: -10%;
  left: 50%;
  transform: translateX(-50%);
  width: 800px;
  height: 500px;
  background: radial-gradient(circle, rgba(0, 242, 254, 0.12) 0%, rgba(157, 78, 221, 0.08) 50%, transparent 80%);
  filter: blur(80px);
  z-index: -1;
  pointer-events: none;
}

.glow-bg-2 {
  position: absolute;
  top: 45%;
  right: -10%;
  width: 600px;
  height: 600px;
  background: radial-gradient(circle, rgba(157, 78, 221, 0.12) 0%, rgba(79, 172, 254, 0.08) 50%, transparent 80%);
  filter: blur(100px);
  z-index: -1;
  pointer-events: none;
}

a {
  color: var(--primary-cyan);
  text-decoration: none;
  transition: all 0.3s ease;
}

a:hover {
  color: #64ffda;
}

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 20px;
}

/* Navbar */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 1000;
  background: rgba(7, 10, 20, 0.85);
  backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border-color);
  transition: all 0.3s ease;
}

.navbar .container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 76px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 1.6rem;
  font-weight: 800;
  letter-spacing: -0.5px;
  color: #fff;
}

.logo span {
  background: linear-gradient(135deg, var(--primary-cyan), var(--primary-blue));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.logo-badge {
  font-size: 0.7rem;
  padding: 2px 8px;
  border-radius: 12px;
  background: rgba(0, 242, 254, 0.15);
  color: var(--primary-cyan);
  border: 1px solid rgba(0, 242, 254, 0.3);
  font-weight: 600;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 28px;
  list-style: none;
}

.nav-links a {
  color: var(--text-sub);
  font-size: 0.95rem;
  font-weight: 500;
  position: relative;
  padding: 6px 0;
}

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0%;
  height: 2px;
  background: linear-gradient(90deg, var(--primary-cyan), var(--primary-blue));
  transition: width 0.3s ease;
  border-radius: 2px;
}

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

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

.btn-cta {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 24px;
  border-radius: 8px;
  font-weight: 600;
  font-size: 0.95rem;
  background: linear-gradient(135deg, var(--primary-cyan), #00b4d8);
  color: #040914;
  box-shadow: 0 4px 15px rgba(0, 242, 254, 0.3);
  border: none;
  cursor: pointer;
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.btn-cta:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(0, 242, 254, 0.5);
  color: #000;
}

.mobile-menu-btn {
  display: none;
  background: none;
  border: none;
  color: #fff;
  font-size: 1.5rem;
  cursor: pointer;
}

/* Mobile Nav Drawer */
.mobile-nav {
  display: none;
  position: fixed;
  top: 76px;
  left: 0;
  width: 100%;
  background: #090d1a;
  border-bottom: 1px solid var(--border-color);
  padding: 20px;
  z-index: 999;
}

.mobile-nav.open {
  display: block;
}

.mobile-nav ul {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.mobile-nav a {
  font-size: 1.1rem;
  color: var(--text-main);
  display: block;
}

/* Hero Section */
.hero {
  padding: 160px 0 100px 0;
  text-align: center;
  position: relative;
}

.hero-tag {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 16px;
  border-radius: 20px;
  background: rgba(0, 242, 254, 0.08);
  border: 1px solid rgba(0, 242, 254, 0.25);
  color: var(--primary-cyan);
  font-size: 0.85rem;
  font-weight: 600;
  margin-bottom: 24px;
}

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

@keyframes pulse {
  0% { transform: scale(0.95); box-shadow: 0 0 0 0 rgba(0, 242, 254, 0.7); }
  70% { transform: scale(1); box-shadow: 0 0 0 10px rgba(0, 242, 254, 0); }
  100% { transform: scale(0.95); box-shadow: 0 0 0 0 rgba(0, 242, 254, 0); }
}

.hero h1 {
  font-size: 3.5rem;
  font-weight: 800;
  line-height: 1.2;
  margin-bottom: 24px;
  letter-spacing: -1px;
}

.hero h1 .gradient-text {
  background: linear-gradient(135deg, #ffffff 30%, var(--primary-cyan) 70%, var(--accent-purple) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero p {
  font-size: 1.2rem;
  color: var(--text-muted);
  max-width: 720px;
  margin: 0 auto 36px auto;
}

.hero-actions {
  display: flex;
  justify-content: center;
  gap: 16px;
  margin-bottom: 60px;
  flex-wrap: wrap;
}

.btn-secondary {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 10px 24px;
  border-radius: 8px;
  font-weight: 600;
  font-size: 0.95rem;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid var(--border-color);
  color: var(--text-main);
  transition: all 0.3s ease;
}

.btn-secondary:hover {
  background: rgba(255, 255, 255, 0.1);
  border-color: rgba(255, 255, 255, 0.3);
  color: #fff;
}

.hero-stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  max-width: 900px;
  margin: 0 auto;
  padding: 24px;
  border-radius: 16px;
  background: var(--bg-glass);
  border: 1px solid var(--border-color);
  backdrop-filter: blur(12px);
}

.stat-item h3 {
  font-size: 1.8rem;
  font-weight: 700;
  color: var(--primary-cyan);
  margin-bottom: 4px;
}

.stat-item p {
  font-size: 0.85rem;
  color: var(--text-muted);
  margin: 0;
}

/* Section Title */
.section-header {
  text-align: center;
  margin-bottom: 60px;
}

.section-subtitle {
  color: var(--primary-cyan);
  font-size: 0.9rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 2px;
  margin-bottom: 10px;
  display: block;
}

.section-title {
  font-size: 2.2rem;
  font-weight: 800;
  color: #fff;
  margin-bottom: 16px;
}

.section-desc {
  color: var(--text-muted);
  font-size: 1.05rem;
  max-width: 640px;
  margin: 0 auto;
}

/* Core Advantages Grid */
.features-section {
  padding: 80px 0;
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.feature-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 16px;
  padding: 32px;
  transition: all 0.3s ease;
  position: relative;
  overflow: hidden;
}

.feature-card:hover {
  transform: translateY(-5px);
  border-color: var(--border-glow);
  box-shadow: var(--shadow-glow);
  background: var(--bg-card-hover);
}

.feature-icon {
  width: 54px;
  height: 54px;
  border-radius: 12px;
  background: rgba(0, 242, 254, 0.1);
  border: 1px solid rgba(0, 242, 254, 0.2);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  color: var(--primary-cyan);
  margin-bottom: 20px;
}

.feature-card h3 {
  font-size: 1.25rem;
  color: #fff;
  margin-bottom: 12px;
  font-weight: 700;
}

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

/* Pricing Section - Matching Screenshot */
.pricing-section {
  padding: 80px 0;
  position: relative;
}

.pricing-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  align-items: stretch;
  max-width: 1100px;
  margin: 0 auto;
}

.pricing-card {
  background: #0d1222;
  border: 1px solid #1e293b;
  border-radius: 16px;
  padding: 36px 28px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  position: relative;
  transition: all 0.3s ease;
}

.pricing-card:hover {
  border-color: #3b82f6;
  box-shadow: 0 0 30px rgba(59, 130, 246, 0.2);
}

/* Highlighted middle card (流量套餐 1 in user screenshot) */
.pricing-card.featured {
  border: 2px solid #a855f7;
  background: #11152a;
  box-shadow: 0 0 35px rgba(168, 85, 247, 0.25);
  transform: scale(1.03);
}

.pricing-card.featured:hover {
  box-shadow: 0 0 45px rgba(168, 85, 247, 0.4);
}

.badge-popular {
  position: absolute;
  top: 0;
  right: 0;
  background: linear-gradient(135deg, #d946ef, #a855f7);
  color: #fff;
  font-size: 0.75rem;
  font-weight: 700;
  padding: 4px 16px;
  border-bottom-left-radius: 12px;
  border-top-right-radius: 14px;
  letter-spacing: 1px;
}

.pricing-card.card-cyan {
  border: 1px solid #00f2fe;
  box-shadow: 0 0 20px rgba(0, 242, 254, 0.15);
}

.pricing-header h3 {
  font-size: 1.4rem;
  font-weight: 700;
  color: #fff;
  margin-bottom: 20px;
}

.pricing-price {
  margin-bottom: 28px;
}

.pricing-price .currency {
  font-size: 1.5rem;
  font-weight: 800;
  color: #fff;
}

.pricing-card.featured .pricing-price .currency,
.pricing-card.featured .pricing-price .amount {
  color: #e879f9;
}

.pricing-price .amount {
  font-size: 2.8rem;
  font-weight: 900;
  color: #fff;
  letter-spacing: -1px;
}

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

.pricing-features {
  list-style: none;
  margin-bottom: 36px;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.pricing-features li {
  display: flex;
  align-items: center;
  gap: 12px;
  color: #cbd5e1;
  font-size: 0.95rem;
  font-weight: 500;
}

.pricing-features li i {
  font-size: 1.1rem;
  color: #00f2fe;
}

.pricing-card.featured .pricing-features li i {
  color: #a855f7;
}

.btn-price {
  width: 100%;
  padding: 14px 0;
  border-radius: 8px;
  font-size: 1rem;
  font-weight: 700;
  text-align: center;
  cursor: pointer;
  transition: all 0.3s ease;
  border: 1px solid rgba(0, 242, 254, 0.4);
  background: transparent;
  color: var(--primary-cyan);
  display: block;
}

.btn-price:hover {
  background: rgba(0, 242, 254, 0.15);
  border-color: var(--primary-cyan);
  box-shadow: 0 0 15px rgba(0, 242, 254, 0.3);
}

.pricing-card.featured .btn-price {
  background: linear-gradient(135deg, #00f2fe, #a855f7);
  color: #fff;
  border: none;
  box-shadow: 0 4px 20px rgba(168, 85, 247, 0.4);
}

.pricing-card.featured .btn-price:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 25px rgba(168, 85, 247, 0.6);
}

.pricing-card.card-cyan .btn-price {
  border: 1px solid var(--primary-cyan);
  color: var(--primary-cyan);
}

.pricing-card.card-cyan .btn-price:hover {
  background: var(--primary-cyan);
  color: #040914;
}

/* Tutorials & Downloads */
.tutorial-section {
  padding: 80px 0;
}

.client-tabs {
  display: flex;
  justify-content: center;
  gap: 12px;
  margin-bottom: 36px;
  flex-wrap: wrap;
}

.tab-btn {
  padding: 10px 24px;
  border-radius: 30px;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid var(--border-color);
  color: var(--text-sub);
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s ease;
  display: flex;
  align-items: center;
  gap: 8px;
}

.tab-btn.active, .tab-btn:hover {
  background: rgba(0, 242, 254, 0.15);
  border-color: var(--primary-cyan);
  color: var(--primary-cyan);
}

.tab-content {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 16px;
  padding: 36px;
  display: none;
}

.tab-content.active {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 36px;
  align-items: center;
}

.tutorial-steps {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.step-item {
  display: flex;
  gap: 16px;
}

.step-num {
  width: 32px;
  height: 32px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--primary-cyan), var(--primary-blue));
  color: #040914;
  font-weight: 800;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.step-info h4 {
  font-size: 1.05rem;
  color: #fff;
  margin-bottom: 4px;
}

.step-info p {
  font-size: 0.9rem;
  color: var(--text-muted);
}

/* Knowledge Base Grid & Tags */
.kb-section {
  padding: 80px 0;
}

.tag-cloud {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  justify-content: center;
  margin-bottom: 40px;
  max-width: 900px;
  margin-left: auto;
  margin-right: auto;
}

.tag-item {
  padding: 6px 14px;
  border-radius: 20px;
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid var(--border-color);
  color: var(--text-sub);
  font-size: 0.85rem;
  cursor: pointer;
  transition: all 0.3s ease;
}

.tag-item:hover {
  background: rgba(0, 242, 254, 0.15);
  border-color: var(--primary-cyan);
  color: var(--primary-cyan);
  transform: translateY(-2px);
}

.articles-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.article-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 16px;
  padding: 28px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  transition: all 0.3s ease;
}

.article-card:hover {
  transform: translateY(-5px);
  border-color: var(--border-glow);
  box-shadow: var(--shadow-glow);
}

.article-meta {
  display: flex;
  gap: 12px;
  font-size: 0.8rem;
  color: var(--primary-cyan);
  margin-bottom: 12px;
  font-weight: 600;
}

.article-card h3 {
  font-size: 1.15rem;
  color: #fff;
  line-height: 1.5;
  margin-bottom: 12px;
  font-weight: 700;
}

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

.read-more {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--primary-cyan);
}

/* Reviews / Testimonials */
.reviews-section {
  padding: 80px 0;
}

.reviews-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.review-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 16px;
  padding: 28px;
}

.review-header {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-bottom: 16px;
}

.avatar {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--primary-cyan), var(--accent-purple));
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  color: #fff;
}

.user-info h4 {
  font-size: 1rem;
  color: #fff;
}

.stars {
  color: #f59e0b;
  font-size: 0.85rem;
}

.review-card p {
  color: var(--text-sub);
  font-size: 0.9rem;
  line-height: 1.6;
}

/* FAQ Accordion */
.faq-section {
  padding: 80px 0;
}

.faq-list {
  max-width: 800px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.faq-item {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 12px;
  overflow: hidden;
  transition: all 0.3s ease;
}

.faq-question {
  padding: 20px 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  cursor: pointer;
  font-weight: 600;
  font-size: 1.05rem;
  color: #fff;
}

.faq-question i {
  transition: transform 0.3s ease;
  color: var(--primary-cyan);
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s ease;
  background: rgba(0, 0, 0, 0.2);
}

.faq-answer p {
  padding: 0 24px 20px 24px;
  color: var(--text-muted);
  font-size: 0.95rem;
  line-height: 1.6;
}

.faq-item.active .faq-question i {
  transform: rotate(180deg);
}

/* Footer */
.footer {
  background: #040711;
  border-top: 1px solid var(--border-color);
  padding: 60px 0 30px 0;
  color: var(--text-muted);
  font-size: 0.9rem;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 40px;
  margin-bottom: 40px;
}

.footer-brand p {
  margin-top: 14px;
  font-size: 0.9rem;
  color: var(--text-muted);
  max-width: 320px;
}

.footer-col h4 {
  color: #fff;
  font-size: 1rem;
  margin-bottom: 18px;
}

.footer-col ul {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.footer-col a {
  color: var(--text-muted);
}

.footer-col a:hover {
  color: var(--primary-cyan);
}

.footer-bottom {
  text-align: center;
  padding-top: 30px;
  border-top: 1px solid rgba(255, 255, 255, 0.05);
}

/* Article Page Specific Styles */
.article-page {
  padding-top: 120px;
  padding-bottom: 80px;
}

.article-container {
  display: grid;
  grid-template-columns: 1fr 320px;
  gap: 40px;
}

.article-main {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 16px;
  padding: 40px;
}

.breadcrumb {
  display: flex;
  gap: 8px;
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-bottom: 20px;
}

.breadcrumb a {
  color: var(--text-muted);
}

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

.article-header h1 {
  font-size: 2.2rem;
  color: #fff;
  line-height: 1.35;
  margin-bottom: 16px;
}

.article-details {
  display: flex;
  gap: 20px;
  font-size: 0.85rem;
  color: var(--text-muted);
  padding-bottom: 24px;
  border-bottom: 1px solid var(--border-color);
  margin-bottom: 32px;
}

.article-content {
  color: #e2e8f0;
  font-size: 1.05rem;
  line-height: 1.85;
}

.article-content h2 {
  font-size: 1.5rem;
  color: #fff;
  margin: 36px 0 16px 0;
  padding-bottom: 8px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.article-content h3 {
  font-size: 1.25rem;
  color: var(--primary-cyan);
  margin: 24px 0 12px 0;
}

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

.article-content ul, .article-content ol {
  margin-bottom: 24px;
  padding-left: 24px;
}

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

.article-cta-box {
  background: linear-gradient(135deg, rgba(0, 242, 254, 0.1), rgba(157, 78, 221, 0.15));
  border: 1px solid var(--primary-cyan);
  border-radius: 12px;
  padding: 32px;
  text-align: center;
  margin: 40px 0;
}

.article-cta-box h3 {
  font-size: 1.4rem;
  color: #fff;
  margin-bottom: 10px;
}

.article-cta-box p {
  font-size: 0.95rem;
  color: var(--text-muted);
  margin-bottom: 20px;
}

.article-sidebar {
  display: flex;
  flex-direction: column;
  gap: 24px;
}

.sidebar-box {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 16px;
  padding: 24px;
}

.sidebar-box h3 {
  color: #fff;
  font-size: 1.1rem;
  margin-bottom: 16px;
  border-bottom: 1px solid var(--border-color);
  padding-bottom: 10px;
}

.related-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.related-list a {
  color: var(--text-sub);
  font-size: 0.9rem;
  display: block;
  line-height: 1.4;
}

.related-list a:hover {
  color: var(--primary-cyan);
}

/* Mobile Responsive */
@media (max-width: 992px) {
  .hero h1 { font-size: 2.5rem; }
  .features-grid, .pricing-grid, .articles-grid, .reviews-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .pricing-card.featured { transform: none; }
  .tab-content.active { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .article-container { grid-template-columns: 1fr; }
}

@media (max-width: 768px) {
  .nav-links { display: none; }
  .mobile-menu-btn { display: block; }
  .hero h1 { font-size: 2.1rem; }
  .hero-stats { grid-template-columns: repeat(2, 1fr); }
  .features-grid, .pricing-grid, .articles-grid, .reviews-grid {
    grid-template-columns: 1fr;
  }
  .footer-grid { grid-template-columns: 1fr; }
}