/* CSS Variables for Easy Theming */
:root {
  --bg-color: #0d0e15;
  --bg-surface: #151722;
  --text-primary: #f1f5f9;
  --text-secondary: #94a3b8;
  --accent-primary: #6366f1;
  --accent-secondary: #0ea5e9;
  --border-color: rgba(255, 255, 255, 0.08);
  --glass-bg: rgba(21, 23, 34, 0.6);
  
  --font-sans: 'Inter', system-ui, sans-serif;
  --font-display: 'Outfit', system-ui, sans-serif;
}

/* Reset & Base Styles */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-sans);
  background-color: var(--bg-color);
  color: var(--text-primary);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

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

ul {
  list-style: none;
}

.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

/* Typography Utilities */
.text-gradient {
  background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

h1, h2, h3, h4 {
  font-family: var(--font-display);
  line-height: 1.2;
}

/* Navbar */
.navbar {
  position: fixed;
  top: 0;
  width: 100%;
  padding: 20px 0;
  z-index: 100;
  transition: all 0.3s ease;
}

.navbar.scrolled {
  padding: 12px 0;
  background: var(--glass-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-color);
}

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

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
}

.brand-icon {
  color: var(--accent-primary);
}

.brand-text {
  font-family: var(--font-display);
  font-size: 1.5rem;
  font-weight: 800;
  letter-spacing: -0.5px;
}

.nav-links {
  display: flex;
  gap: 32px;
}

.nav-link {
  color: var(--text-secondary);
  font-weight: 500;
  transition: color 0.2s ease;
}

.nav-link:hover {
  color: var(--text-primary);
}

.mobile-menu-btn {
  display: none;
  background: none;
  border: none;
  color: var(--text-primary);
  cursor: pointer;
}

.mobile-menu {
  display: none;
  flex-direction: column;
  background: var(--bg-surface);
  border-bottom: 1px solid var(--border-color);
  padding: 20px 24px;
  position: absolute;
  top: 100%;
  left: 0;
  width: 100%;
}

.mobile-menu.active {
  display: flex;
}

.mobile-link {
  padding: 12px 0;
  color: var(--text-secondary);
  border-bottom: 1px solid var(--border-color);
}

.mobile-link:last-child {
  border-bottom: none;
}

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

.hero-bg-glow {
  position: absolute;
  top: 20%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 600px;
  height: 600px;
  background: radial-gradient(circle, rgba(99, 102, 241, 0.15) 0%, transparent 70%);
  z-index: -1;
  pointer-events: none;
}

.hero-content {
  max-width: 800px;
  margin: 0 auto;
}

.badge {
  display: inline-block;
  padding: 6px 16px;
  border-radius: 20px;
  background: rgba(99, 102, 241, 0.1);
  color: var(--accent-primary);
  font-size: 0.85rem;
  font-weight: 600;
  margin-bottom: 24px;
  border: 1px solid rgba(99, 102, 241, 0.2);
}

.hero-title {
  font-size: 4rem;
  margin-bottom: 24px;
  letter-spacing: -1px;
}

.hero-subtitle {
  font-size: 1.25rem;
  color: var(--text-secondary);
  margin-bottom: 40px;
}

.hero-cta {
  display: flex;
  gap: 16px;
  justify-content: center;
}

.btn {
  padding: 14px 28px;
  border-radius: 8px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s ease;
  font-size: 1rem;
}

.btn-primary {
  background: var(--accent-primary);
  color: white;
  border: 1px solid var(--accent-primary);
}

.btn-primary:hover {
  background: transparent;
  color: var(--accent-primary);
}

.btn-secondary {
  background: transparent;
  color: var(--text-primary);
  border: 1px solid var(--border-color);
}

.btn-secondary:hover {
  border-color: var(--text-primary);
}

/* Articles Section */
.articles {
  padding: 80px 0;
}

.section-header {
  text-align: center;
  margin-bottom: 60px;
}

.section-header h2 {
  font-size: 2.5rem;
  margin-bottom: 12px;
}

.section-header p {
  color: var(--text-secondary);
  font-size: 1.1rem;
}

.articles-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 30px;
}

.article-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: 16px;
  padding: 30px;
  transition: transform 0.3s ease, border-color 0.3s ease;
  display: flex;
  flex-direction: column;
}

.article-card:hover {
  transform: translateY(-5px);
  border-color: var(--accent-primary);
}

.card-category {
  font-size: 0.8rem;
  color: var(--accent-secondary);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 1px;
  margin-bottom: 16px;
}

.article-card h3 {
  font-size: 1.5rem;
  margin-bottom: 12px;
}

.article-card p {
  color: var(--text-secondary);
  margin-bottom: 24px;
  flex-grow: 1;
}

.card-footer {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-top: 20px;
  border-top: 1px solid var(--border-color);
}

.card-date {
  font-size: 0.9rem;
  color: var(--text-secondary);
}

.card-link {
  color: var(--accent-primary);
  font-weight: 600;
  font-size: 0.95rem;
}

.card-link:hover {
  text-decoration: underline;
}

/* FAQ Section */
.faq {
  padding: 80px 0 120px;
}

.faq-container {
  max-width: 800px;
  margin: 0 auto;
}

.faq-item {
  border-bottom: 1px solid var(--border-color);
}

.faq-item:first-child {
  border-top: 1px solid var(--border-color);
}

.faq-question {
  width: 100%;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 24px 0;
  background: none;
  border: none;
  color: var(--text-primary);
  font-size: 1.2rem;
  font-weight: 600;
  font-family: var(--font-sans);
  cursor: pointer;
  text-align: left;
}

.faq-question .chevron {
  transition: transform 0.3s ease;
  color: var(--text-secondary);
}

.faq-item.active .chevron {
  transform: rotate(180deg);
  color: var(--accent-primary);
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s ease;
}

.faq-item.active .faq-answer {
  max-height: 200px; /* arbitrary large value */
}

.faq-answer p {
  padding-bottom: 24px;
  color: var(--text-secondary);
}

/* Footer */
.footer {
  background: var(--bg-surface);
  border-top: 1px solid var(--border-color);
  padding: 60px 0;
  text-align: center;
}

.footer-brand {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
  margin-bottom: 16px;
}

.footer-desc {
  color: var(--text-secondary);
  margin-bottom: 24px;
}

.copyright {
  font-size: 0.9rem;
  color: var(--text-secondary);
  opacity: 0.7;
}

/* Animations */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.fade-in-up {
  opacity: 0;
  animation: fadeInUp 0.6s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}

/* Responsive */
@media (max-width: 768px) {
  .desktop-only {
    display: none;
  }
  
  .mobile-menu-btn {
    display: block;
  }
  
  .hero-title {
    font-size: 2.8rem;
  }
  
  .hero-cta {
    flex-direction: column;
  }
  
  .btn {
    width: 100%;
  }
}