/* Dear Charlie - Minimalist Visual Blog */

:root {
  --color-bg: #FAFAFA;
  --color-text: #1A1A1D;
  --color-text-light: #6E6E73;
  --color-accent: #2E86AB;
  --color-accent-dark: #1A5276;
  --color-border: #E5E5E7;
  --color-white: #FFFFFF;
  --spacing-xs: 0.5rem;
  --spacing-sm: 1rem;
  --spacing-md: 2rem;
  --spacing-lg: 4rem;
  --spacing-xl: 6rem;
  --max-width: 1400px;
  --font-sans: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen', 'Ubuntu', sans-serif;
  --font-serif: 'Georgia', 'Times New Roman', serif;
}

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

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

body {
  font-family: var(--font-sans);
  background-color: var(--color-bg);
  color: var(--color-text);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* Typography */
h1, h2, h3, h4 {
  font-family: var(--font-serif);
  font-weight: 600;
  line-height: 1.2;
  margin-bottom: var(--spacing-sm);
}

h1 {
  font-size: 3.5rem;
  letter-spacing: -0.02em;
}

h2 {
  font-size: 2.5rem;
  letter-spacing: -0.01em;
}

h3 {
  font-size: 1.75rem;
}

p {
  margin-bottom: var(--spacing-sm);
  color: var(--color-text-light);
}

a {
  color: var(--color-accent);
  text-decoration: none;
  transition: color 0.2s ease;
}

a:hover {
  color: var(--color-accent-dark);
}

/* Header */
.site-header {
  background: var(--color-white);
  border-bottom: 1px solid var(--color-border);
  position: sticky;
  top: 0;
  z-index: 1000;
  backdrop-filter: blur(10px);
  background: rgba(255, 255, 255, 0.95);
}

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

.site-title {
  font-family: var(--font-serif);
  font-size: 2rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--color-text);
}

.site-tagline {
  font-size: 0.875rem;
  color: var(--color-text-light);
  margin-top: var(--spacing-xs);
}

.nav-menu {
  display: flex;
  gap: var(--spacing-md);
  list-style: none;
}

.nav-menu a {
  font-size: 0.9375rem;
  font-weight: 500;
  color: var(--color-text);
  padding: var(--spacing-xs) var(--spacing-sm);
  border-radius: 4px;
  transition: background 0.2s ease;
}

.nav-menu a:hover {
  background: var(--color-bg);
}

/* Hero Section */
.hero {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: var(--spacing-xl) var(--spacing-md);
  text-align: center;
}

.hero h1 {
  margin-bottom: var(--spacing-md);
}

.hero-subtitle {
  font-size: 1.25rem;
  color: var(--color-text-light);
  max-width: 700px;
  margin: 0 auto var(--spacing-lg);
  line-height: 1.7;
}

.stats-bar {
  display: flex;
  justify-content: center;
  gap: var(--spacing-lg);
  flex-wrap: wrap;
}

.stat-item {
  text-align: center;
}

.stat-number {
  font-size: 2.5rem;
  font-weight: 700;
  color: var(--color-accent);
  display: block;
}

.stat-label {
  font-size: 0.875rem;
  color: var(--color-text-light);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

/* Visualizations Section */
.visualizations {
  background: var(--color-white);
  padding: var(--spacing-xl) var(--spacing-md);
  border-top: 1px solid var(--color-border);
  border-bottom: 1px solid var(--color-border);
}

.visualizations-container {
  max-width: var(--max-width);
  margin: 0 auto;
}

.visualizations h2 {
  text-align: center;
  margin-bottom: var(--spacing-lg);
}

.viz-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(500px, 1fr));
  gap: var(--spacing-lg);
  margin-top: var(--spacing-lg);
}

.viz-item {
  background: var(--color-bg);
  padding: var(--spacing-md);
  border-radius: 8px;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.05);
}

.viz-item img {
  width: 100%;
  height: auto;
  border-radius: 4px;
}

/* Image Gallery */
.gallery {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: var(--spacing-xl) var(--spacing-md);
}

.gallery-header {
  text-align: center;
  margin-bottom: var(--spacing-lg);
}

.gallery-filters {
  display: flex;
  justify-content: center;
  gap: var(--spacing-sm);
  flex-wrap: wrap;
  margin-top: var(--spacing-md);
}

.filter-btn {
  padding: var(--spacing-xs) var(--spacing-md);
  border: 1px solid var(--color-border);
  background: var(--color-white);
  color: var(--color-text);
  border-radius: 20px;
  font-size: 0.875rem;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.2s ease;
}

.filter-btn:hover,
.filter-btn.active {
  background: var(--color-accent);
  color: var(--color-white);
  border-color: var(--color-accent);
}

.gallery-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: var(--spacing-md);
  margin-top: var(--spacing-lg);
}

.gallery-item {
  position: relative;
  aspect-ratio: 4 / 3;
  overflow: hidden;
  border-radius: 8px;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
  cursor: pointer;
}

.gallery-item:hover {
  transform: translateY(-4px);
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.12);
}

.gallery-item img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.3s ease;
}

.gallery-item:hover img {
  transform: scale(1.05);
}

.gallery-item-overlay {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  background: linear-gradient(to top, rgba(0, 0, 0, 0.8), transparent);
  padding: var(--spacing-md);
  color: var(--color-white);
  opacity: 0;
  transition: opacity 0.3s ease;
}

.gallery-item:hover .gallery-item-overlay {
  opacity: 1;
}

.gallery-item-source {
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  opacity: 0.9;
}

.gallery-item-date {
  font-size: 0.875rem;
  margin-top: var(--spacing-xs);
}

/* Article Page */
.article {
  max-width: 900px;
  margin: 0 auto;
  padding: var(--spacing-xl) var(--spacing-md);
}

.article-header {
  text-align: center;
  margin-bottom: var(--spacing-lg);
}

.article-meta {
  display: flex;
  justify-content: center;
  gap: var(--spacing-md);
  color: var(--color-text-light);
  font-size: 0.875rem;
  margin-top: var(--spacing-md);
}

.article-image {
  width: 100%;
  height: auto;
  border-radius: 8px;
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.1);
  margin: var(--spacing-lg) 0;
}

.article-content {
  font-size: 1.125rem;
  line-height: 1.8;
  color: var(--color-text);
}

.article-nav {
  display: flex;
  justify-content: space-between;
  margin-top: var(--spacing-xl);
  padding-top: var(--spacing-md);
  border-top: 1px solid var(--color-border);
}

.article-nav-btn {
  padding: var(--spacing-sm) var(--spacing-md);
  background: var(--color-white);
  border: 1px solid var(--color-border);
  border-radius: 4px;
  color: var(--color-text);
  font-weight: 500;
  cursor: pointer;
  transition: all 0.2s ease;
}

.article-nav-btn:hover {
  background: var(--color-accent);
  color: var(--color-white);
  border-color: var(--color-accent);
}

/* Social Share */
.social-share {
  display: flex;
  gap: var(--spacing-sm);
  justify-content: center;
  margin: var(--spacing-lg) 0;
}

.share-btn {
  display: inline-flex;
  align-items: center;
  gap: var(--spacing-xs);
  padding: var(--spacing-sm) var(--spacing-md);
  background: var(--color-white);
  border: 1px solid var(--color-border);
  border-radius: 4px;
  color: var(--color-text);
  font-size: 0.875rem;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.2s ease;
}

.share-btn:hover {
  background: var(--color-bg);
  transform: translateY(-2px);
}

/* Footer */
.site-footer {
  background: var(--color-text);
  color: var(--color-bg);
  padding: var(--spacing-lg) var(--spacing-md);
  text-align: center;
  margin-top: var(--spacing-xl);
}

.footer-content {
  max-width: var(--max-width);
  margin: 0 auto;
}

.footer-content p {
  color: var(--color-bg);
  opacity: 0.7;
}

/* Responsive Design */
@media (max-width: 768px) {
  html {
    font-size: 14px;
  }

  h1 {
    font-size: 2.5rem;
  }

  h2 {
    font-size: 2rem;
  }

  .header-container {
    flex-direction: column;
    gap: var(--spacing-sm);
    text-align: center;
  }

  .nav-menu {
    flex-direction: column;
    gap: var(--spacing-xs);
  }

  .gallery-grid {
    grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
    gap: var(--spacing-sm);
  }

  .viz-grid {
    grid-template-columns: 1fr;
  }

  .stats-bar {
    gap: var(--spacing-md);
  }
}

/* Loading Animation */
.loading {
  text-align: center;
  padding: var(--spacing-xl);
  color: var(--color-text-light);
}

/* Utilities */
.text-center {
  text-align: center;
}

.mt-lg {
  margin-top: var(--spacing-lg);
}

.mb-lg {
  margin-bottom: var(--spacing-lg);
}

/* Compact Hero Section */
.hero-compact {
  padding: var(--spacing-md) var(--spacing-md) var(--spacing-sm);
}

.hero-compact h1 {
  font-size: 2.5rem;
  margin-bottom: var(--spacing-xs);
}

.hero-compact .hero-subtitle {
  font-size: 1rem;
  margin: 0 auto;
}

/* Blog Post Styles */
.post-container {
  max-width: 800px;
  margin: 0 auto;
  padding: var(--spacing-lg) var(--spacing-md);
}

.post-header {
  text-align: center;
  margin-bottom: var(--spacing-lg);
}

.post-title {
  font-size: 2.5rem;
  margin-bottom: var(--spacing-sm);
  line-height: 1.3;
}

.post-meta {
  display: flex;
  justify-content: center;
  gap: var(--spacing-md);
  font-size: 0.875rem;
  color: var(--color-text-light);
}

.post-source {
  font-weight: 600;
  color: var(--color-accent);
}

.post-image {
  margin: var(--spacing-lg) 0;
}

.post-image img {
  width: 100%;
  height: auto;
  border-radius: 8px;
}

.post-content {
  font-family: var(--font-serif);
  font-size: 1.125rem;
  line-height: 1.8;
  color: var(--color-text);
}

.post-content p {
  margin-bottom: var(--spacing-md);
  color: var(--color-text);
}

.post-footer {
  margin-top: var(--spacing-xl);
  padding-top: var(--spacing-lg);
  border-top: 1px solid var(--color-border);
}

.post-info {
  margin-bottom: var(--spacing-lg);
  padding: var(--spacing-md);
  background: var(--color-bg);
  border-radius: 8px;
}

.post-info p {
  margin-bottom: var(--spacing-xs);
  font-size: 0.875rem;
}

.post-navigation {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: var(--spacing-md);
  flex-wrap: wrap;
}

.btn-back,
.btn-next,
.btn-prev {
  padding: var(--spacing-sm) var(--spacing-md);
  background: var(--color-white);
  border: 1px solid var(--color-border);
  border-radius: 4px;
  color: var(--color-text);
  font-weight: 500;
  transition: all 0.2s ease;
  text-decoration: none;
  display: inline-block;
}

.btn-back:hover,
.btn-next:hover,
.btn-prev:hover {
  background: var(--color-accent);
  color: var(--color-white);
  border-color: var(--color-accent);
}

.post-nav-buttons {
  display: flex;
  gap: var(--spacing-sm);
}

@media (max-width: 768px) {
  .post-title {
    font-size: 2rem;
  }
  
  .post-content {
    font-size: 1rem;
  }
  
  .post-navigation {
    flex-direction: column;
  }
  
  .post-nav-buttons {
    width: 100%;
    justify-content: space-between;
  }
}