/* Modern CSS with optimized design system */

:root {
  /* Light theme colors */
  --primary-color: #2563eb;
  --secondary-color: #7c3aed;
  --accent-color: #06b6d4;
  --text-primary: #1f2937;
  --text-secondary: #6b7280;
  --bg-primary: #ffffff;
  --bg-secondary: #f9fafb;
  --bg-card: #ffffff;
  --border-color: #e5e7eb;
  --code-bg: #f3f4f6;
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
  --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

[data-theme="dark"] {
  /* Dark theme colors */
  --primary-color: #3b82f6;
  --secondary-color: #8b5cf6;
  --accent-color: #06b6d4;
  --text-primary: #f9fafb;
  --text-secondary: #d1d5db;
  --bg-primary: #111827;
  --bg-secondary: #1f2937;
  --bg-card: #1f2937;
  --border-color: #374151;
  --code-bg: #0f172a;
}

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

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

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen', 'Ubuntu', 'Cantarell', 'Fira Sans', 'Droid Sans', 'Helvetica Neue', sans-serif;
  line-height: 1.6;
  color: var(--text-primary);
  background-color: var(--bg-primary);
  transition: var(--transition);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* Modern Navigation */
.navigation {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: rgba(255, 255, 255, 0.9);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border-color);
  box-shadow: var(--shadow-sm);
  transition: var(--transition);
}

[data-theme="dark"] .navigation {
  background: rgba(17, 24, 39, 0.9);
}

.navigation .container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 1rem 2rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.navigation-title {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--text-primary);
  text-decoration: none;
  transition: var(--transition);
}

.navigation-title:hover {
  color: var(--primary-color);
  transform: scale(1.05);
}

.navigation-list {
  display: flex;
  list-style: none;
  gap: 2rem;
  align-items: center;
}

.navigation-link {
  color: var(--text-primary);
  text-decoration: none;
  font-weight: 500;
  position: relative;
  transition: var(--transition);
  padding: 0.5rem 0;
}

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

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

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

/* Mobile Menu Button - Hidden on desktop */
.menu-button {
  display: none;
  cursor: pointer;
  font-size: 1.5rem;
  color: var(--text-primary);
  padding: 0.5rem;
}

#menu-toggle {
  display: none;
}

.float-right {
  float: right;
}

/* Hero Section */
.hero {
  padding: 6rem 2rem;
  text-align: center;
  background: var(--bg-primary);
  position: relative;
  overflow: hidden;
}

@keyframes pulse {
  0%, 100% { transform: scale(1); opacity: 0.5; }
  50% { transform: scale(1.1); opacity: 0.8; }
}

.about {
  position: relative;
  z-index: 1;
}

.avatar {
  margin-bottom: 2rem;
  animation: fadeInUp 0.8s ease-out;
}

.avatar img {
  width: 150px;
  height: 150px;
  border-radius: 50%;
  object-fit: cover;
  box-shadow: var(--shadow-xl);
  transition: var(--transition);
}

.avatar img:hover {
  transform: scale(1.1) rotate(5deg);
  box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.2);
}

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.about h1 {
  font-size: 3rem;
  font-weight: 800;
  margin-bottom: 0.5rem;
  color: var(--text-primary);
  animation: fadeInUp 0.8s ease-out 0.2s both;
}

.about h2 {
  font-size: 1.5rem;
  color: var(--text-secondary);
  font-weight: 400;
  margin-bottom: 2rem;
  animation: fadeInUp 0.8s ease-out 0.4s both;
}

.about ul {
  list-style: none;
  display: flex;
  justify-content: center;
  gap: 1.5rem;
  flex-wrap: wrap;
  animation: fadeInUp 0.8s ease-out 0.6s both;
}

.about ul li a {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 50px;
  height: 50px;
  border-radius: 50%;
  background: var(--bg-card);
  color: var(--text-primary);
  font-size: 1.5rem;
  text-decoration: none;
  box-shadow: var(--shadow-md);
  transition: var(--transition);
  border: 2px solid var(--border-color);
}

.about ul li a:hover {
  transform: translateY(-5px) scale(1.1);
  box-shadow: var(--shadow-xl);
  background: var(--primary-color);
  color: #ffffff;
  border-color: var(--primary-color);
}

/* Content Sections */
.content {
  max-width: 1200px;
  margin: 0 auto;
  padding: 4rem 2rem;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 2rem;
}

/* Cards */
.card {
  background: var(--bg-card);
  border-radius: 12px;
  padding: 2rem;
  box-shadow: var(--shadow-md);
  border: 1px solid var(--border-color);
  transition: var(--transition);
  margin-bottom: 2rem;
}

.card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-xl);
}

/* Blog Posts */
.post-list {
  list-style: none;
}

.post-item {
  background: var(--bg-card);
  border-radius: 12px;
  padding: 2rem;
  margin-bottom: 2rem;
  box-shadow: var(--shadow-md);
  border: 1px solid var(--border-color);
  transition: var(--transition);
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.post-item:hover {
  transform: translateX(10px);
  box-shadow: var(--shadow-xl);
  border-color: var(--primary-color);
}

.post-item .date {
  color: var(--text-secondary);
  font-size: 0.875rem;
  font-weight: 500;
}

.post-item .title {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--text-primary);
  text-decoration: none;
  transition: var(--transition);
}

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

/* Code Blocks */
pre {
  background: var(--code-bg);
  border-radius: 8px;
  padding: 1.5rem;
  overflow-x: auto;
  border: 1px solid var(--border-color);
  box-shadow: var(--shadow-sm);
}

code {
  font-family: 'Fira Code', 'Monaco', 'Courier New', monospace;
  font-size: 0.9em;
  color: var(--text-primary);
}

pre code {
  background: transparent;
  padding: 0;
  color: inherit;
}

/* Data Visualization Containers */
.data-viz {
  margin: 2rem 0;
  padding: 2rem;
  background: var(--bg-card);
  border-radius: 12px;
  box-shadow: var(--shadow-md);
  border: 1px solid var(--border-color);
}

.data-viz canvas,
.data-viz svg {
  max-width: 100%;
  height: auto;
}

/* Footer */
.footer {
  background: var(--bg-secondary);
  padding: 3rem 2rem;
  text-align: center;
  border-top: 1px solid var(--border-color);
  margin-top: 4rem;
}

.footer p {
  color: var(--text-secondary);
  margin-bottom: 1rem;
}

/* Dark Mode Toggle */
.theme-toggle {
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  width: 50px;
  height: 50px;
  border-radius: 50%;
  background: var(--bg-card);
  border: 2px solid var(--border-color);
  color: var(--text-primary);
  font-size: 1.5rem;
  cursor: pointer;
  box-shadow: var(--shadow-lg);
  transition: var(--transition);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 1000;
}

.theme-toggle:hover {
  transform: scale(1.1) rotate(180deg);
  box-shadow: var(--shadow-xl);
}

/* Responsive Design */
@media (max-width: 768px) {
  .menu-button {
    display: block;
  }

  .navigation-list {
    flex-direction: column;
    gap: 1rem;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--bg-card);
    padding: 1rem;
    box-shadow: var(--shadow-lg);
    display: none;
    border-top: 1px solid var(--border-color);
  }

  .navigation-list.active {
    display: flex;
  }

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

  .content {
    padding: 2rem 1rem;
  }

  .hero {
    padding: 4rem 1rem;
  }
}

/* Animations */
@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

@keyframes slideIn {
  from {
    opacity: 0;
    transform: translateX(-20px);
  }
  to {
    opacity: 1;
    transform: translateX(0);
  }
}

.fade-in {
  animation: fadeIn 0.6s ease-out;
}

.slide-in {
  animation: slideIn 0.6s ease-out;
}

/* Smooth transitions for theme changes */
* {
  transition: background-color 0.3s ease, color 0.3s ease, border-color 0.3s ease;
}