/* ===================================
   Design System & CSS Variables
   =================================== */
:root {
  /* Colors */
  --bg-primary: #0a0a0f;
  --bg-secondary: #12121a;
  --bg-card: rgba(255, 255, 255, 0.03);
  --bg-card-hover: rgba(255, 255, 255, 0.06);
  
  --text-primary: #ffffff;
  --text-secondary: #a0a0b0;
  --text-muted: #606070;
  
  --accent-primary: #6366f1;
  --accent-secondary: #8b5cf6;
  --accent-tertiary: #ec4899;
  
  --border-color: rgba(255, 255, 255, 0.08);
  --border-hover: rgba(255, 255, 255, 0.15);
  
  /* Gradients */
  --gradient-primary: linear-gradient(135deg, #6366f1 0%, #8b5cf6 50%, #ec4899 100%);
  --gradient-bg: radial-gradient(ellipse at top, #1a1a2e 0%, #0a0a0f 50%);
  
  /* Spacing */
  --space-xs: 0.25rem;
  --space-sm: 0.5rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2rem;
  --space-2xl: 3rem;
  --space-3xl: 4rem;
  
  /* Border Radius */
  --radius-sm: 0.5rem;
  --radius-md: 0.75rem;
  --radius-lg: 1rem;
  --radius-xl: 1.5rem;
  
  /* Shadows */
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.3);
  --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.4);
  --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.5);
  --shadow-glow: 0 0 40px rgba(99, 102, 241, 0.15);
  
  /* Typography */
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', monospace;
  
  /* Transitions */
  --transition-fast: 150ms ease;
  --transition-base: 250ms ease;
  --transition-slow: 400ms ease;
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: var(--font-sans);
  background: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  min-height: 100vh;
  overflow-x: hidden;
}

/* Animated Background */
body::before {
  content: '';
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: var(--gradient-bg);
  z-index: -2;
}

body::after {
  content: '';
  position: fixed;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background: 
    radial-gradient(circle at 20% 80%, rgba(99, 102, 241, 0.08) 0%, transparent 50%),
    radial-gradient(circle at 80% 20%, rgba(139, 92, 246, 0.08) 0%, transparent 50%),
    radial-gradient(circle at 40% 40%, rgba(236, 72, 153, 0.05) 0%, transparent 40%);
  animation: float 20s ease-in-out infinite;
  z-index: -1;
}

@keyframes float {
  0%, 100% { transform: translate(0, 0) rotate(0deg); }
  33% { transform: translate(2%, 2%) rotate(1deg); }
  66% { transform: translate(-1%, 1%) rotate(-1deg); }
}

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

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

/* ===================================
   Typography
   =================================== */
h1, h2, h3, h4, h5, h6 {
  font-weight: 600;
  line-height: 1.3;
  letter-spacing: -0.02em;
}

h1 { font-size: clamp(2rem, 5vw, 3.5rem); }
h2 { font-size: clamp(1.5rem, 4vw, 2.5rem); }
h3 { font-size: clamp(1.25rem, 3vw, 1.75rem); }

p {
  color: var(--text-secondary);
}

/* ===================================
   Layout Components
   =================================== */
.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--space-lg);
}

/* ===================================
   Navigation
   =================================== */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  padding: var(--space-md) 0;
  background: rgba(10, 10, 15, 0.8);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border-color);
  transition: var(--transition-base);
}

.navbar.scrolled {
  padding: var(--space-sm) 0;
  background: rgba(10, 10, 15, 0.95);
}

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

.nav-logo {
  font-size: 1.5rem;
  font-weight: 700;
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: var(--space-xl);
  list-style: none;
}

.nav-link {
  position: relative;
  color: var(--text-secondary);
  font-weight: 500;
  transition: var(--transition-fast);
}

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

.nav-link::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--gradient-primary);
  transition: var(--transition-base);
}

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

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: var(--space-sm);
}

.nav-toggle span {
  width: 24px;
  height: 2px;
  background: var(--text-primary);
  transition: var(--transition-fast);
}

/* ===================================
   Hero Section
   =================================== */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: var(--space-3xl) 0;
  position: relative;
}

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

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: var(--space-sm);
  padding: var(--space-sm) var(--space-md);
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 50px;
  font-size: 0.875rem;
  color: var(--text-secondary);
  margin-bottom: var(--space-xl);
}

.hero-badge-dot {
  width: 8px;
  height: 8px;
  background: #22c55e;
  border-radius: 50%;
  animation: pulse 2s ease-in-out infinite;
}

@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.5; }
}

.hero-title {
  margin-bottom: var(--space-lg);
}

.hero-title .highlight {
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-description {
  font-size: 1.25rem;
  max-width: 600px;
  margin: 0 auto var(--space-2xl);
}

.hero-buttons {
  display: flex;
  gap: var(--space-md);
  justify-content: center;
  flex-wrap: wrap;
}

/* ===================================
   Buttons
   =================================== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-sm);
  padding: var(--space-md) var(--space-xl);
  font-size: 1rem;
  font-weight: 500;
  border-radius: var(--radius-md);
  border: none;
  cursor: pointer;
  transition: var(--transition-base);
}

.btn-primary {
  background: var(--gradient-primary);
  color: white;
  box-shadow: var(--shadow-glow);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 0 60px rgba(99, 102, 241, 0.3);
}

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

.btn-secondary:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-hover);
}

/* ===================================
   Section Styles
   =================================== */
.section {
  padding: var(--space-3xl) 0;
}

.section-header {
  text-align: center;
  margin-bottom: var(--space-2xl);
}

.section-title {
  margin-bottom: var(--space-md);
}

.section-description {
  max-width: 600px;
  margin: 0 auto;
}

/* ===================================
   Blog Cards Grid
   =================================== */
.posts-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
  gap: var(--space-xl);
}

.post-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: var(--transition-base);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
}

.post-card:hover {
  transform: translateY(-4px);
  border-color: var(--border-hover);
  box-shadow: var(--shadow-lg);
}

.post-image {
  position: relative;
  height: 200px;
  overflow: hidden;
}

.post-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: var(--transition-slow);
}

.post-card:hover .post-image img {
  transform: scale(1.05);
}

.post-image-placeholder {
  width: 100%;
  height: 100%;
  background: linear-gradient(135deg, var(--accent-primary) 0%, var(--accent-secondary) 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 3rem;
}

.post-content {
  padding: var(--space-lg);
}

.post-meta {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  margin-bottom: var(--space-md);
  font-size: 0.875rem;
  color: var(--text-muted);
}

.post-tag {
  padding: var(--space-xs) var(--space-sm);
  background: rgba(99, 102, 241, 0.1);
  color: var(--accent-primary);
  border-radius: var(--radius-sm);
  font-size: 0.75rem;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.post-title {
  font-size: 1.25rem;
  margin-bottom: var(--space-sm);
  transition: var(--transition-fast);
}

.post-card:hover .post-title {
  color: var(--accent-primary);
}

.post-excerpt {
  font-size: 0.9375rem;
  color: var(--text-secondary);
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

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

.post-author {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}

.author-avatar {
  width: 32px;
  height: 32px;
  border-radius: 50%;
  background: var(--gradient-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.875rem;
  font-weight: 600;
}

.author-name {
  font-size: 0.875rem;
  font-weight: 500;
}

.post-read-time {
  font-size: 0.875rem;
  color: var(--text-muted);
}

/* ===================================
   Footer
   =================================== */
.footer {
  padding: var(--space-2xl) 0;
  border-top: 1px solid var(--border-color);
  background: var(--bg-secondary);
}

.footer-content {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-lg);
  text-align: center;
}

.footer-logo {
  font-size: 1.5rem;
  font-weight: 700;
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.footer-links {
  display: flex;
  gap: var(--space-xl);
  list-style: none;
}

.footer-link {
  color: var(--text-secondary);
  transition: var(--transition-fast);
}

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

.footer-social {
  display: flex;
  gap: var(--space-md);
}

.social-link {
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 50%;
  color: var(--text-secondary);
  transition: var(--transition-base);
}

.social-link:hover {
  background: var(--bg-card-hover);
  border-color: var(--accent-primary);
  color: var(--accent-primary);
}

.footer-copyright {
  font-size: 0.875rem;
  color: var(--text-muted);
}

/* ===================================
   Article Page Styles
   =================================== */
.article {
  padding-top: 100px;
  padding-bottom: var(--space-3xl);
}

.article-header {
  max-width: 800px;
  margin: 0 auto var(--space-2xl);
  text-align: center;
}

.article-meta {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-lg);
  margin-bottom: var(--space-lg);
  flex-wrap: wrap;
}

.article-title {
  margin-bottom: var(--space-lg);
}

.article-cover {
  max-width: 1000px;
  margin: 0 auto var(--space-2xl);
  border-radius: var(--radius-xl);
  overflow: hidden;
}

.article-cover img {
  width: 100%;
  height: auto;
}

.article-content {
  max-width: 720px;
  margin: 0 auto;
  font-size: 1.125rem;
  line-height: 1.8;
}

.article-content h2 {
  margin-top: var(--space-2xl);
  margin-bottom: var(--space-lg);
}

.article-content h3 {
  margin-top: var(--space-xl);
  margin-bottom: var(--space-md);
}

.article-content p {
  margin-bottom: var(--space-lg);
  color: var(--text-secondary);
}

.article-content a {
  color: var(--accent-primary);
  text-decoration: underline;
  text-underline-offset: 2px;
}

.article-content a:hover {
  color: var(--accent-secondary);
}

.article-content ul,
.article-content ol {
  margin-bottom: var(--space-lg);
  padding-left: var(--space-xl);
  color: var(--text-secondary);
}

.article-content li {
  margin-bottom: var(--space-sm);
}

.article-content code {
  font-family: var(--font-mono);
  background: var(--bg-card);
  padding: var(--space-xs) var(--space-sm);
  border-radius: var(--radius-sm);
  font-size: 0.9em;
}

.article-content pre {
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: var(--space-lg);
  overflow-x: auto;
  margin-bottom: var(--space-lg);
}

.article-content pre code {
  background: none;
  padding: 0;
}

.article-content blockquote {
  border-left: 3px solid var(--accent-primary);
  padding-left: var(--space-lg);
  margin: var(--space-xl) 0;
  font-style: italic;
  color: var(--text-secondary);
}

/* ===================================
   Back to Top Button
   =================================== */
.back-to-top {
  position: fixed;
  bottom: var(--space-xl);
  right: var(--space-xl);
  width: 48px;
  height: 48px;
  background: var(--gradient-primary);
  border: none;
  border-radius: 50%;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  visibility: hidden;
  transition: var(--transition-base);
  box-shadow: var(--shadow-glow);
  z-index: 100;
}

.back-to-top.visible {
  opacity: 1;
  visibility: visible;
}

.back-to-top:hover {
  transform: translateY(-4px);
}

.back-to-top svg {
  width: 24px;
  height: 24px;
  fill: white;
}

/* ===================================
   Responsive Design
   =================================== */
@media (max-width: 768px) {
  html {
    font-size: 14px;
  }
  
  .nav-links {
    position: fixed;
    top: 60px;
    left: 0;
    right: 0;
    background: rgba(10, 10, 15, 0.98);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    flex-direction: column;
    padding: var(--space-xl);
    gap: var(--space-lg);
    border-bottom: 1px solid var(--border-color);
    transform: translateY(-100%);
    opacity: 0;
    visibility: hidden;
    transition: var(--transition-base);
  }
  
  .nav-links.active {
    transform: translateY(0);
    opacity: 1;
    visibility: visible;
  }
  
  .nav-toggle {
    display: flex;
  }
  
  .hero {
    min-height: auto;
    padding: 120px 0 var(--space-3xl);
  }
  
  .hero-buttons {
    flex-direction: column;
    align-items: center;
  }
  
  .posts-grid {
    grid-template-columns: 1fr;
  }
  
  .footer-links {
    flex-direction: column;
    gap: var(--space-md);
  }
}

@media (max-width: 480px) {
  .container {
    padding: 0 var(--space-md);
  }
  
  .btn {
    width: 100%;
    justify-content: center;
  }
  
  .article-meta {
    flex-direction: column;
    gap: var(--space-sm);
  }
}