/* ============================================
   10-ai.ru — Modern AI & Tech Blog
   ============================================ */

/* --- Fonts --- */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700;800&display=swap');

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

:root {
  /* Light theme */
  --bg: #ffffff;
  --bg-alt: #f8f9fa;
  --bg-card: #ffffff;
  --text: #1a1a2e;
  --text-secondary: #6b7280;
  --text-muted: #9ca3af;
  --border: #e5e7eb;
  --border-hover: #d1d5db;
  --accent: #6366f1;
  --accent-hover: #4f46e5;
  --accent-gradient: linear-gradient(135deg, #6366f1 0%, #8b5cf6 50%, #a855f7 100%);
  --accent-gradient-2: linear-gradient(135deg, #4f46e5 0%, #7c3aed 100%);
  --shadow-sm: 0 1px 2px rgba(0,0,0,0.05);
  --shadow: 0 1px 3px rgba(0,0,0,0.08), 0 1px 2px rgba(0,0,0,0.06);
  --shadow-md: 0 4px 6px -1px rgba(0,0,0,0.1), 0 2px 4px -2px rgba(0,0,0,0.1);
  --shadow-lg: 0 10px 15px -3px rgba(0,0,0,0.1), 0 4px 6px -4px rgba(0,0,0,0.1);
  --radius: 12px;
  --radius-sm: 8px;
  --radius-lg: 16px;
  --font: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --max-width: 1200px;
  --header-height: 64px;
}

[data-theme="dark"] {
  --bg: #0a0a1a;
  --bg-alt: #0f0f2a;
  --bg-card: #12122e;
  --text: #e8e8f0;
  --text-secondary: #9ca3af;
  --text-muted: #6b7280;
  --border: #1e1e3a;
  --border-hover: #2e2e4a;
  --shadow-sm: 0 1px 2px rgba(0,0,0,0.2);
  --shadow: 0 1px 3px rgba(0,0,0,0.3), 0 1px 2px rgba(0,0,0,0.2);
  --shadow-md: 0 4px 6px -1px rgba(0,0,0,0.4), 0 2px 4px -2px rgba(0,0,0,0.3);
  --shadow-lg: 0 10px 15px -3px rgba(0,0,0,0.4), 0 4px 6px -4px rgba(0,0,0,0.3);
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  transition: background 0.3s, color 0.3s;
  min-height: 100vh;
}

/* --- Header --- */
.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--header-height);
  background: var(--bg);
  border-bottom: 1px solid var(--border);
  z-index: 100;
  transition: background 0.3s, border-color 0.3s;
}

.header-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.logo {
  font-size: 1.25rem;
  font-weight: 800;
  background: var(--accent-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  text-decoration: none;
  letter-spacing: -0.5px;
}

.logo:hover {
  opacity: 0.9;
}

.nav {
  display: flex;
  align-items: center;
  gap: 24px;
}

.nav a {
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 0.9rem;
  font-weight: 500;
  transition: color 0.2s;
}

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

/* Theme Toggle */
.theme-toggle {
  background: none;
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 6px 10px;
  cursor: pointer;
  color: var(--text-secondary);
  font-size: 1.1rem;
  line-height: 1;
  transition: border-color 0.2s, color 0.2s;
}

.theme-toggle:hover {
  border-color: var(--accent);
  color: var(--accent);
}

/* --- Main Content --- */
.main {
  padding-top: calc(var(--header-height) + 40px);
  padding-bottom: 60px;
}

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
}

/* --- Hero --- */
.hero {
  text-align: center;
  padding: 40px 0 48px;
}

.hero h1 {
  font-size: clamp(1.8rem, 4vw, 3rem);
  font-weight: 800;
  line-height: 1.2;
  letter-spacing: -1px;
  margin-bottom: 16px;
}

.hero h1 span {
  background: var(--accent-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero p {
  font-size: 1.1rem;
  color: var(--text-secondary);
  max-width: 640px;
  margin: 0 auto 24px;
}

.hero-meta {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
  flex-wrap: wrap;
  font-size: 0.85rem;
  color: var(--text-muted);
}

.hero-meta .dot {
  width: 4px;
  height: 4px;
  border-radius: 50%;
  background: var(--text-muted);
}

/* --- Articles Grid --- */
.section-title {
  font-size: 1.5rem;
  font-weight: 700;
  margin-bottom: 24px;
  letter-spacing: -0.5px;
}

.articles-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(340px, 1fr));
  gap: 24px;
}

.article-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  transition: transform 0.2s, box-shadow 0.2s, border-color 0.2s;
}

.article-card:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
  border-color: var(--border-hover);
}

.article-card-image {
  width: 100%;
  height: 200px;
  object-fit: cover;
  display: block;
  background: var(--bg-alt);
}

.article-card-body {
  padding: 20px;
}

.article-card-category {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  color: var(--accent);
  margin-bottom: 8px;
}

.article-card-title {
  font-size: 1.1rem;
  font-weight: 700;
  line-height: 1.4;
  margin-bottom: 8px;
  letter-spacing: -0.3px;
}

.article-card-title a {
  color: var(--text);
  text-decoration: none;
  transition: color 0.2s;
}

.article-card-title a:hover {
  color: var(--accent);
}

.article-card-excerpt {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.6;
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.article-card-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-top: 16px;
  padding-top: 16px;
  border-top: 1px solid var(--border);
  font-size: 0.8rem;
  color: var(--text-muted);
}

.article-card-readmore {
  color: var(--accent);
  text-decoration: none;
  font-weight: 600;
  font-size: 0.85rem;
  transition: opacity 0.2s;
}

.article-card-readmore:hover {
  opacity: 0.8;
}

/* --- Article Page --- */
.article-page {
  max-width: 720px;
  margin: 0 auto;
  padding-top: 40px;
}

.article-header {
  margin-bottom: 32px;
}

.article-category {
  display: inline-block;
  font-size: 0.8rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  color: var(--accent);
  margin-bottom: 12px;
}

.article-title {
  font-size: clamp(1.6rem, 3vw, 2.4rem);
  font-weight: 800;
  line-height: 1.25;
  letter-spacing: -1px;
  margin-bottom: 16px;
}

.article-meta {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 12px;
  font-size: 0.85rem;
  color: var(--text-secondary);
}

.article-meta .dot {
  width: 3px;
  height: 3px;
  border-radius: 50%;
  background: var(--text-secondary);
}

.article-featured-image {
  width: 100%;
  border-radius: var(--radius);
  margin-bottom: 32px;
  background: var(--bg-alt);
}

/* --- Article Content Typography --- */
.article-content {
  font-size: 1.05rem;
  line-height: 1.8;
  color: var(--text);
}

.article-content h2 {
  font-size: 1.5rem;
  font-weight: 700;
  margin: 36px 0 16px;
  letter-spacing: -0.5px;
  line-height: 1.3;
}

.article-content h3 {
  font-size: 1.2rem;
  font-weight: 600;
  margin: 28px 0 12px;
}

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

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

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

.article-content img {
  width: 100%;
  border-radius: var(--radius-sm);
  margin: 24px 0;
}

.article-content ul, .article-content ol {
  margin: 0 0 20px 24px;
}

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

.article-content blockquote {
  border-left: 4px solid var(--accent);
  padding: 16px 20px;
  margin: 24px 0;
  background: var(--bg-alt);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  font-style: italic;
  color: var(--text-secondary);
}

.article-content blockquote p:last-child {
  margin-bottom: 0;
}

.article-content code {
  background: var(--bg-alt);
  padding: 2px 6px;
  border-radius: 4px;
  font-size: 0.9em;
  font-family: 'JetBrains Mono', 'Fira Code', monospace;
}

.article-content pre {
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 20px;
  overflow-x: auto;
  margin: 24px 0;
}

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

.article-content hr {
  border: none;
  border-top: 1px solid var(--border);
  margin: 40px 0;
}

/* --- Tags --- */
.article-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 32px;
  padding-top: 24px;
  border-top: 1px solid var(--border);
}

.tag {
  display: inline-block;
  padding: 4px 12px;
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: 20px;
  font-size: 0.8rem;
  color: var(--text-secondary);
  text-decoration: none;
  transition: border-color 0.2s, color 0.2s;
}

.tag:hover {
  border-color: var(--accent);
  color: var(--accent);
}

/* --- Share --- */
.article-share {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-top: 24px;
  padding-top: 24px;
  border-top: 1px solid var(--border);
}

.article-share span {
  font-size: 0.85rem;
  color: var(--text-secondary);
  font-weight: 500;
}

.share-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 8px 16px;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  background: var(--bg);
  color: var(--text-secondary);
  font-size: 0.85rem;
  font-weight: 500;
  cursor: pointer;
  transition: border-color 0.2s, color 0.2s;
  text-decoration: none;
}

.share-btn:hover {
  border-color: var(--accent);
  color: var(--accent);
}

/* --- Footer --- */
.footer {
  border-top: 1px solid var(--border);
  padding: 32px 0;
  margin-top: 40px;
}

.footer-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 16px;
}

.footer-copy {
  font-size: 0.85rem;
  color: var(--text-muted);
}

.footer-links {
  display: flex;
  gap: 20px;
}

.footer-links a {
  color: var(--text-muted);
  text-decoration: none;
  font-size: 0.85rem;
  transition: color 0.2s;
}

.footer-links a:hover {
  color: var(--accent);
}

/* --- Yandex RYA Ad Placeholder --- */
.ad-block {
  background: var(--bg-alt);
  border: 1px dashed var(--border);
  border-radius: var(--radius-sm);
  padding: 20px;
  margin: 32px 0;
  text-align: center;
  font-size: 0.85rem;
  color: var(--text-muted);
}

.ad-block-inside {
  margin: 24px 0;
}

/* --- Pagination --- */
.pagination {
  display: flex;
  justify-content: center;
  gap: 8px;
  margin-top: 40px;
}

.pagination a, .pagination span {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 40px;
  height: 40px;
  padding: 0 12px;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--text);
  text-decoration: none;
  transition: border-color 0.2s, color 0.2s, background 0.2s;
}

.pagination a:hover {
  border-color: var(--accent);
  color: var(--accent);
}

.pagination .active {
  background: var(--accent-gradient);
  color: white;
  border-color: transparent;
}

/* --- Newsletter / Subscribe --- */
.subscribe-box {
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 32px;
  margin: 40px 0;
  text-align: center;
}

.subscribe-box h3 {
  font-size: 1.2rem;
  font-weight: 700;
  margin-bottom: 8px;
}

.subscribe-box p {
  color: var(--text-secondary);
  font-size: 0.9rem;
  margin-bottom: 20px;
}

.subscribe-form {
  display: flex;
  gap: 8px;
  max-width: 420px;
  margin: 0 auto;
}

.subscribe-form input {
  flex: 1;
  padding: 10px 16px;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  background: var(--bg);
  color: var(--text);
  font-size: 0.9rem;
  outline: none;
  transition: border-color 0.2s;
}

.subscribe-form input:focus {
  border-color: var(--accent);
}

.subscribe-form button {
  padding: 10px 20px;
  background: var(--accent-gradient);
  color: white;
  border: none;
  border-radius: var(--radius-sm);
  font-weight: 600;
  font-size: 0.9rem;
  cursor: pointer;
  transition: opacity 0.2s;
}

.subscribe-form button:hover {
  opacity: 0.9;
}

/* --- Breadcrumbs --- */
.breadcrumbs {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-bottom: 20px;
}

.breadcrumbs a {
  color: var(--text-secondary);
  text-decoration: none;
}

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

.breadcrumbs .sep {
  color: var(--text-muted);
}

/* --- Responsive --- */
@media (max-width: 768px) {
  .header-inner {
    padding: 0 16px;
  }
  
  .container {
    padding: 0 16px;
  }
  
  .hero {
    padding: 24px 0 32px;
  }
  
  .articles-grid {
    grid-template-columns: 1fr;
  }
  
  .article-card-image {
    height: 180px;
  }
  
  .subscribe-form {
    flex-direction: column;
  }
  
  .footer-inner {
    flex-direction: column;
    text-align: center;
  }
}

@media (max-width: 480px) {
  .nav {
    gap: 16px;
  }
  
  .article-title {
    font-size: 1.4rem;
  }
  
  .article-content {
    font-size: 1rem;
  }
}

/* --- Animations --- */
@keyframes fadeIn {
  from { opacity: 0; transform: translateY(8px); }
  to { opacity: 1; transform: translateY(0); }
}

.animate-in {
  animation: fadeIn 0.4s ease-out;
}

/* --- Scrollbar --- */
::-webkit-scrollbar {
  width: 8px;
}

::-webkit-scrollbar-track {
  background: var(--bg-alt);
}

::-webkit-scrollbar-thumb {
  background: var(--border);
  border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
  background: var(--text-muted);
}

/* --- 404 --- */
.error-page {
  text-align: center;
  padding: 80px 24px;
}

.error-page h1 {
  font-size: 4rem;
  font-weight: 800;
  background: var(--accent-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: 16px;
}

.error-page p {
  font-size: 1.1rem;
  color: var(--text-secondary);
  margin-bottom: 24px;
}

.error-page a {
  display: inline-block;
  padding: 12px 24px;
  background: var(--accent-gradient);
  color: white;
  border-radius: var(--radius-sm);
  text-decoration: none;
  font-weight: 600;
  transition: opacity 0.2s;
}

.error-page a:hover {
  opacity: 0.9;
}