/* ============================================================
   TechMazed Blog — Design System
   Dark-themed, reading-first, Medium-inspired with engineering edge
   ============================================================ */

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

:root {
  --bg: #030712;
  --bg-raised: #0a0f1a;
  --bg-card: rgba(255,255,255,0.025);
  --bg-card-hover: rgba(255,255,255,0.05);
  --border: rgba(255,255,255,0.06);
  --border-hover: rgba(255,255,255,0.12);
  --text-primary: #f1f5f9;
  --text-body: #cbd5e1;
  --text-muted: #64748b;
  --text-faint: #334155;
  --accent: #3b82f6;
  --accent-light: #60a5fa;
  --accent-violet: #8b5cf6;
  --font-sans: 'Inter', system-ui, -apple-system, sans-serif;
  --font-serif: 'Newsreader', 'Georgia', 'Times New Roman', serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', monospace;
  --max-width: 1200px;
  --content-width: 720px;
  --transition: 0.3s ease;
}

html { scroll-behavior: smooth; }

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

::selection { background: rgba(59,130,246,0.3); color: #fff; }

a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }

/* Scrollbar */
::-webkit-scrollbar { width: 5px; }
::-webkit-scrollbar-track { background: var(--bg); }
::-webkit-scrollbar-thumb { background: #1e293b; border-radius: 3px; }

/* --- Reading Progress Bar --- */
.reading-progress {
  position: fixed; top: 0; left: 0;
  height: 2px; width: 0%;
  background: linear-gradient(90deg, var(--accent), var(--accent-violet));
  z-index: 100;
  transition: width 0.1s linear;
}

/* --- Navigation --- */
.nav {
  position: fixed; top: 0; left: 0; right: 0;
  height: 60px; z-index: 50;
  transition: background var(--transition), border-color var(--transition), backdrop-filter var(--transition);
  border-bottom: 1px solid transparent;
}
.nav.scrolled {
  background: rgba(3,7,18,0.85);
  backdrop-filter: blur(20px) saturate(1.4);
  -webkit-backdrop-filter: blur(20px) saturate(1.4);
  border-bottom-color: var(--border);
}
.nav-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 1.25rem;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.nav-logo {
  display: flex; align-items: center; gap: 0.5rem;
  font-size: 1.125rem; font-weight: 700;
}
.nav-logo .t { color: var(--text-primary); }
.nav-logo .m { color: var(--accent); }
.nav-logo .sep { color: var(--text-faint); margin: 0 0.25rem; font-weight: 300; }
.nav-logo .blog-label { color: var(--text-muted); font-weight: 400; font-size: 0.875rem; }

.nav-links { display: flex; align-items: center; gap: 1.75rem; }
.nav-links a {
  font-size: 0.8125rem; color: var(--text-muted);
  transition: color var(--transition);
  letter-spacing: 0.01em;
}
.nav-links a:hover { color: var(--text-primary); }
.nav-links a.active { color: var(--text-primary); font-weight: 500; }

/* Mobile nav */
.nav-toggle { display: none; background: none; border: none; color: var(--text-muted); cursor: pointer; padding: 0.5rem; }
.nav-toggle svg { width: 22px; height: 22px; }

.mobile-menu {
  display: none;
  position: fixed; top: 60px; left: 0; right: 0;
  background: rgba(3,7,18,0.95);
  backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border);
  padding: 1rem 1.25rem;
}
.mobile-menu.open { display: flex; flex-direction: column; gap: 0.75rem; }
.mobile-menu a { font-size: 0.9375rem; color: var(--text-muted); padding: 0.5rem 0; transition: color var(--transition); }
.mobile-menu a:hover { color: var(--text-primary); }

@media (max-width: 640px) {
  .nav-links { display: none; }
  .nav-toggle { display: block; }
}

/* --- Layout Containers --- */
.container { max-width: var(--max-width); margin: 0 auto; padding: 0 1.25rem; }
.content-width { max-width: var(--content-width); margin: 0 auto; }

/* --- Hero / Page Headers --- */
.page-header {
  padding: 7rem 0 3rem;
  text-align: center;
}
.page-header .overline {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.15em;
  margin-bottom: 1rem;
}
.page-header h1 {
  font-size: clamp(2rem, 5vw, 3rem);
  font-weight: 800;
  color: var(--text-primary);
  letter-spacing: -0.03em;
  line-height: 1.15;
  margin-bottom: 1rem;
}
.page-header .subtitle {
  font-size: 1.0625rem;
  color: var(--text-muted);
  max-width: 560px;
  margin: 0 auto;
  line-height: 1.6;
}

/* --- Dividers --- */
.glow-line {
  height: 1px; width: 100%;
  background: linear-gradient(90deg, transparent, rgba(59,130,246,0.25), rgba(139,92,246,0.2), transparent);
  margin: 0;
}
.divider {
  border: none;
  border-top: 1px solid var(--border);
  margin: 2rem 0;
}

/* --- Topic Pills / Tags --- */
.topics { display: flex; flex-wrap: wrap; gap: 0.5rem; }
.topic {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  padding: 0.3rem 0.7rem;
  border-radius: 9999px;
  background: rgba(255,255,255,0.04);
  color: var(--text-muted);
  transition: all var(--transition);
  cursor: default;
  letter-spacing: 0.02em;
}
.topic:hover, .topic.active {
  background: rgba(59,130,246,0.12);
  color: var(--accent-light);
}
a.topic { cursor: pointer; }

/* --- Filter Bar --- */
.filter-bar {
  display: flex; flex-wrap: wrap; gap: 0.375rem;
  justify-content: center;
  margin: 2.5rem 0;
}
.filter-btn {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  padding: 0.4rem 0.9rem;
  border-radius: 0.5rem;
  background: transparent;
  color: var(--text-muted);
  border: 1px solid transparent;
  cursor: pointer;
  transition: all var(--transition);
}
.filter-btn:hover {
  color: var(--text-body);
  border-color: var(--border);
}
.filter-btn.active {
  color: var(--text-primary);
  background: rgba(255,255,255,0.06);
  border-color: var(--border-hover);
}

/* --- Featured Article Card --- */
.featured {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 2.5rem;
  align-items: center;
  padding: 2rem;
  border-radius: 1rem;
  background: var(--bg-card);
  border: 1px solid var(--border);
  transition: all 0.5s ease;
  margin-bottom: 3rem;
}
.featured:hover {
  border-color: var(--border-hover);
  background: var(--bg-card-hover);
  box-shadow: 0 0 60px rgba(59,130,246,0.03);
}
.featured-visual {
  aspect-ratio: 16/10;
  border-radius: 0.75rem;
  background: linear-gradient(135deg, rgba(59,130,246,0.08), rgba(139,92,246,0.06), rgba(6,182,212,0.04));
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  overflow: hidden;
}
.featured-visual::before {
  content: '';
  position: absolute; inset: 0;
  background-image: radial-gradient(circle, rgba(148,163,184,0.06) 1px, transparent 1px);
  background-size: 20px 20px;
}
.featured-visual .icon-placeholder {
  font-size: 3rem;
  opacity: 0.15;
}
.featured-content .meta {
  display: flex; align-items: center; gap: 0.75rem;
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: 0.875rem;
}
.featured-content .meta .dot { color: var(--text-faint); }
.featured-content h2 {
  font-size: 1.625rem;
  font-weight: 700;
  color: var(--text-primary);
  letter-spacing: -0.02em;
  line-height: 1.3;
  margin-bottom: 0.75rem;
  transition: color var(--transition);
}
.featured:hover h2 { color: var(--accent-light); }
.featured-content p {
  font-size: 0.9375rem;
  color: var(--text-muted);
  line-height: 1.65;
  margin-bottom: 1rem;
}
.featured-content .read-more {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--accent);
  display: inline-flex; align-items: center; gap: 0.375rem;
  transition: gap var(--transition);
}
.featured:hover .read-more { gap: 0.625rem; }

@media (max-width: 768px) {
  .featured { grid-template-columns: 1fr; gap: 1.5rem; padding: 1.25rem; }
}

/* --- Article Grid --- */
.article-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(340px, 1fr));
  gap: 1.25rem;
}
@media (max-width: 400px) {
  .article-grid { grid-template-columns: 1fr; }
}

/* --- Article Card --- */
.article-card {
  display: flex; flex-direction: column;
  padding: 1.5rem;
  border-radius: 0.875rem;
  background: var(--bg-card);
  border: 1px solid var(--border);
  transition: all 0.4s ease;
}
.article-card:hover {
  border-color: var(--border-hover);
  background: var(--bg-card-hover);
  transform: translateY(-2px);
  box-shadow: 0 8px 40px rgba(0,0,0,0.15);
}
.article-card .card-meta {
  display: flex; align-items: center; gap: 0.625rem;
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  color: var(--text-muted);
  margin-bottom: 0.75rem;
}
.article-card .card-meta .dot { color: var(--text-faint); }
.article-card h3 {
  font-size: 1.125rem;
  font-weight: 650;
  color: var(--text-primary);
  letter-spacing: -0.015em;
  line-height: 1.35;
  margin-bottom: 0.5rem;
  transition: color var(--transition);
}
.article-card:hover h3 { color: var(--accent-light); }
.article-card .card-excerpt {
  font-size: 0.875rem;
  color: var(--text-muted);
  line-height: 1.6;
  flex: 1;
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
}
.article-card .card-footer {
  display: flex; align-items: center; justify-content: space-between;
  margin-top: 1rem;
  padding-top: 0.875rem;
  border-top: 1px solid var(--border);
}
.article-card .card-tags { display: flex; gap: 0.375rem; flex-wrap: wrap; }
.article-card .card-arrow {
  color: var(--text-faint);
  transition: all var(--transition);
  font-size: 1rem;
}
.article-card:hover .card-arrow {
  color: var(--accent);
  transform: translateX(3px);
}

/* --- Article Detail --- */
.article-header {
  padding: 7rem 0 2.5rem;
  max-width: var(--content-width);
  margin: 0 auto;
}
.article-header .back-link {
  display: inline-flex; align-items: center; gap: 0.375rem;
  font-size: 0.8125rem; color: var(--text-muted);
  margin-bottom: 2rem;
  transition: color var(--transition);
}
.article-header .back-link:hover { color: var(--accent-light); }
.article-header .article-topic {
  margin-bottom: 1rem;
}
.article-header h1 {
  font-size: clamp(1.75rem, 4.5vw, 2.75rem);
  font-weight: 800;
  color: var(--text-primary);
  letter-spacing: -0.03em;
  line-height: 1.2;
  margin-bottom: 1.25rem;
}
.article-header .article-subtitle {
  font-size: 1.1875rem;
  color: var(--text-muted);
  line-height: 1.55;
  margin-bottom: 1.5rem;
}
.article-meta-bar {
  display: flex; align-items: center; gap: 1.5rem; flex-wrap: wrap;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--text-muted);
  padding: 1rem 0;
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}
.article-meta-bar .meta-item {
  display: flex; align-items: center; gap: 0.375rem;
}

/* --- Article Body (the reading experience) --- */
.article-body {
  max-width: var(--content-width);
  margin: 0 auto;
  padding: 3rem 0 4rem;
}
.article-body h2 {
  font-family: var(--font-sans);
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--text-primary);
  letter-spacing: -0.02em;
  margin: 2.5rem 0 1rem;
  line-height: 1.3;
}
.article-body h3 {
  font-family: var(--font-sans);
  font-size: 1.1875rem;
  font-weight: 600;
  color: var(--text-primary);
  margin: 2rem 0 0.75rem;
}
.article-body p {
  font-family: var(--font-serif);
  font-size: 1.125rem;
  line-height: 1.8;
  color: var(--text-body);
  margin-bottom: 1.5rem;
}
.article-body p:first-child::first-letter {
  font-size: 3.25rem;
  font-weight: 700;
  float: left;
  line-height: 1;
  margin-right: 0.5rem;
  margin-top: 0.1rem;
  color: var(--text-primary);
  font-family: var(--font-sans);
}
.article-body blockquote {
  border-left: 3px solid var(--accent);
  padding: 0.25rem 0 0.25rem 1.5rem;
  margin: 2rem 0;
}
.article-body blockquote p {
  font-style: italic;
  color: var(--text-primary);
  font-size: 1.1875rem;
}
.article-body code {
  font-family: var(--font-mono);
  font-size: 0.875em;
  background: rgba(255,255,255,0.06);
  padding: 0.15em 0.4em;
  border-radius: 0.25rem;
  color: var(--accent-light);
}
.article-body pre {
  background: var(--bg-raised);
  border: 1px solid var(--border);
  border-radius: 0.75rem;
  padding: 1.25rem 1.5rem;
  overflow-x: auto;
  margin: 1.5rem 0;
  font-size: 0.875rem;
  line-height: 1.65;
}
.article-body pre code {
  background: none;
  padding: 0;
  font-size: inherit;
  color: var(--text-body);
}
.article-body ul, .article-body ol {
  font-family: var(--font-serif);
  font-size: 1.125rem;
  line-height: 1.8;
  color: var(--text-body);
  margin: 1rem 0 1.5rem 1.5rem;
}
.article-body li { margin-bottom: 0.5rem; }
.article-body strong { color: var(--text-primary); font-weight: 600; }
.article-body a {
  color: var(--accent-light);
  text-decoration: underline;
  text-decoration-color: rgba(96,165,250,0.3);
  text-underline-offset: 3px;
  transition: text-decoration-color var(--transition);
}
.article-body a:hover { text-decoration-color: var(--accent-light); }
.article-body hr {
  border: none;
  text-align: center;
  margin: 2.5rem 0;
}
.article-body hr::before {
  content: '· · ·';
  color: var(--text-faint);
  font-size: 1.25rem;
  letter-spacing: 0.5em;
}

/* --- Article End Section --- */
.article-end {
  max-width: var(--content-width);
  margin: 0 auto;
  padding-bottom: 4rem;
}
.article-end .tags-row {
  display: flex; flex-wrap: wrap; gap: 0.5rem;
  margin-bottom: 2rem;
}
.author-card {
  display: flex; gap: 1rem; align-items: center;
  padding: 1.5rem;
  border-radius: 0.875rem;
  background: var(--bg-card);
  border: 1px solid var(--border);
}
.author-avatar {
  width: 48px; height: 48px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--accent), var(--accent-violet));
  display: flex; align-items: center; justify-content: center;
  font-weight: 700; color: #fff; font-size: 1rem;
  flex-shrink: 0;
}
.author-info .author-name { font-weight: 600; color: var(--text-primary); font-size: 0.9375rem; }
.author-info .author-bio { font-size: 0.8125rem; color: var(--text-muted); margin-top: 0.125rem; }

/* --- More Articles (bottom of article page) --- */
.more-articles { margin-top: 2rem; }
.more-articles h4 {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--text-muted);
  margin-bottom: 1.25rem;
}

/* --- Footer --- */
.footer {
  border-top: 1px solid var(--border);
  padding: 3rem 0;
  text-align: center;
}
.footer p {
  font-size: 0.75rem;
  color: var(--text-faint);
}
.footer a { color: var(--text-muted); transition: color var(--transition); }
.footer a:hover { color: var(--accent-light); }
.footer .footer-links {
  display: flex; justify-content: center; gap: 1.5rem;
  margin-bottom: 1rem;
}
.footer .footer-links a { font-size: 0.8125rem; }

/* --- Empty State --- */
.empty-state {
  text-align: center;
  padding: 4rem 1rem;
  color: var(--text-muted);
}

/* --- Utilities --- */
.sr-only {
  position: absolute; width: 1px; height: 1px;
  padding: 0; margin: -1px; overflow: hidden;
  clip: rect(0,0,0,0); border: 0;
}
.mt-section { margin-top: 3rem; }
.mb-section { margin-bottom: 3rem; }