/* ===== RESET & BASE ===== */
*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}

:root {
  --bg-deep: #060a12;
  --bg-base: #0b1120;
  --bg-card: #111b2e;
  --bg-card-hover: #162036;
  --bg-code: #0d1525;
  --border: #1e2d4a;
  --border-glow: #00e87b33;
  --accent: #00e87b;
  --accent-dim: #00e87b99;
  --accent-bright: #33ff99;
  --cyan: #22d3ee;
  --red: #f43f5e;
  --amber: #f59e0b;
  --purple: #a78bfa;
  --text: #d8e3f0;
  --text-muted: #7a8ba8;
  --text-dim: #4a5a74;
  --font-display: 'Orbitron', sans-serif;
  --font-body: 'DM Sans', sans-serif;
  --font-mono: 'Fira Code', 'JetBrains Mono', monospace;
  --max-width: 860px;
  --header-height: 64px;
}

html { scroll-behavior: smooth; }

body {
  font-family: var(--font-body);
  background: var(--bg-deep);
  color: var(--text);
  line-height: 1.7;
  font-size: 16px;
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
}

/* background noise texture */
body::before {
  content: '';
  position: fixed;
  inset: 0;
  background: url("data:image/svg+xml,%3Csvg viewBox='0 0 256 256' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.85' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)' opacity='.03'/%3E%3C/svg%3E");
  pointer-events: none;
  z-index: 0;
}

/* ===== SCANLINE OVERLAY ===== */
body::after {
  content: '';
  position: fixed;
  inset: 0;
  background: repeating-linear-gradient(
    0deg,
    transparent,
    transparent 2px,
    rgba(0,0,0,0.03) 2px,
    rgba(0,0,0,0.03) 4px
  );
  pointer-events: none;
  z-index: 9999;
}

a { color: var(--accent); text-decoration: none; transition: color .2s; }
a:hover { color: var(--accent-bright); }

img { max-width: 100%; height: auto; border-radius: 6px; }

/* ===== HEADER ===== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  height: var(--header-height);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 2rem;
  background: var(--bg-deep);
  border-bottom: 1px solid var(--border);
  backdrop-filter: blur(12px);
}

.site-logo {
  font-family: var(--font-mono);
  font-size: 1.05rem;
  font-weight: 600;
  letter-spacing: .5px;
  color: var(--text);
  display: flex;
  align-items: center;
  gap: .6rem;
}

.site-logo .prefix {
  color: var(--accent);
  font-weight: 700;
}

.site-logo .cursor-blink {
  display: inline-block;
  width: 2px;
  height: 1.2em;
  background: var(--accent);
  animation: blink 1s step-end infinite;
  vertical-align: middle;
}

@keyframes blink { 50% { opacity: 0; } }

.site-logo img {
  width: 28px;
  height: 28px;
  border-radius: 4px;
}

.site-nav {
  display: flex;
  gap: 1.5rem;
  list-style: none;
}

.site-nav a {
  font-family: var(--font-mono);
  font-size: .8rem;
  color: var(--text-muted);
  letter-spacing: 1px;
  text-transform: uppercase;
  position: relative;
  padding-bottom: 2px;
}

.site-nav a::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: 0;
  width: 0;
  height: 1px;
  background: var(--accent);
  transition: width .3s;
}

.site-nav a:hover { color: var(--accent); }
.site-nav a:hover::after { width: 100%; }

/* ===== HERO (INDEX PAGE) ===== */
.hero {
  position: relative;
  padding: 5rem 2rem 4rem;
  text-align: center;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: -120px;
  left: 50%;
  transform: translateX(-50%);
  width: 600px;
  height: 600px;
  background: radial-gradient(circle, var(--accent-dim) 0%, transparent 70%);
  opacity: .12;
  pointer-events: none;
}

.hero h1 {
  font-family: var(--font-display);
  font-size: clamp(2rem, 5vw, 3.2rem);
  font-weight: 900;
  letter-spacing: 3px;
  text-transform: uppercase;
  color: #fff;
  margin-bottom: .75rem;
  position: relative;
}

.hero h1 .accent { color: var(--accent); }

.hero .tagline {
  font-family: var(--font-mono);
  font-size: clamp(.85rem, 2vw, 1rem);
  color: var(--text-muted);
  max-width: 560px;
  margin: 0 auto;
}

.hero .tagline::before { content: '> '; color: var(--accent); }

/* ===== POST GRID ===== */
.posts-section {
  max-width: 960px;
  margin: 0 auto;
  padding: 0 2rem 4rem;
}

.section-label {
  font-family: var(--font-mono);
  font-size: .75rem;
  color: var(--accent);
  letter-spacing: 3px;
  text-transform: uppercase;
  margin-bottom: 1.5rem;
  display: flex;
  align-items: center;
  gap: .75rem;
}

.section-label::after {
  content: '';
  flex: 1;
  height: 1px;
  background: linear-gradient(90deg, var(--border), transparent);
}

.post-card {
  display: block;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 1.5rem 1.75rem;
  margin-bottom: 1rem;
  transition: all .25s ease;
  position: relative;
  overflow: hidden;
}

.post-card::before {
  content: '';
  position: absolute;
  top: 0; left: 0;
  width: 3px;
  height: 100%;
  background: var(--accent);
  opacity: 0;
  transition: opacity .25s;
}

.post-card:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-glow);
  transform: translateX(4px);
  box-shadow: 0 0 30px rgba(0,232,123,.05);
}

.post-card:hover::before { opacity: 1; }

.post-card .meta {
  display: flex;
  align-items: center;
  gap: 1rem;
  margin-bottom: .6rem;
  font-family: var(--font-mono);
  font-size: .75rem;
  color: var(--text-dim);
}

.post-card .meta .date { color: var(--text-muted); }

.post-card .category {
  background: rgba(0,232,123,.1);
  color: var(--accent);
  padding: 2px 8px;
  border-radius: 3px;
  font-size: .7rem;
  text-transform: uppercase;
  letter-spacing: 1px;
  border: 1px solid rgba(0,232,123,.2);
}

.post-card .category.hardware {
  background: rgba(249,115,22,.1);
  color: #fb923c;
  border-color: rgba(249,115,22,.2);
}

.post-card h2 {
  font-family: var(--font-display);
  font-size: 1.1rem;
  font-weight: 700;
  letter-spacing: 1px;
  color: #fff;
  margin-bottom: .5rem;
  transition: color .2s;
}

.post-card:hover h2 { color: var(--accent); }

.post-card .excerpt {
  font-size: .9rem;
  color: var(--text-muted);
  line-height: 1.6;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.post-card .tags {
  display: flex;
  flex-wrap: wrap;
  gap: .4rem;
  margin-top: .75rem;
}

.tag {
  font-family: var(--font-mono);
  font-size: .65rem;
  color: var(--text-dim);
  background: rgba(255,255,255,.04);
  padding: 2px 7px;
  border-radius: 3px;
  letter-spacing: .5px;
}

/* Difficulty badges */
.diff {
  font-family: var(--font-mono);
  font-size: .65rem;
  padding: 2px 8px;
  border-radius: 3px;
  letter-spacing: 1px;
  text-transform: uppercase;
  font-weight: 600;
}
.diff.easy { background: rgba(34,197,94,.12); color: #22c55e; border: 1px solid rgba(34,197,94,.2); }
.diff.medium { background: rgba(245,158,11,.12); color: #f59e0b; border: 1px solid rgba(245,158,11,.2); }
.diff.hard { background: rgba(244,63,94,.12); color: #f43f5e; border: 1px solid rgba(244,63,94,.2); }

/* ===== POST PAGE ===== */
.post-header {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 3rem 2rem 2rem;
  position: relative;
}

.post-header .back-link {
  font-family: var(--font-mono);
  font-size: .8rem;
  color: var(--text-muted);
  display: inline-flex;
  align-items: center;
  gap: .4rem;
  margin-bottom: 1.5rem;
}

.post-header .back-link:hover { color: var(--accent); }

.post-header h1 {
  font-family: var(--font-display);
  font-size: clamp(1.4rem, 4vw, 2rem);
  font-weight: 800;
  letter-spacing: 1.5px;
  color: #fff;
  line-height: 1.3;
  margin-bottom: 1rem;
}

.post-header .post-meta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: .75rem;
  font-family: var(--font-mono);
  font-size: .8rem;
  color: var(--text-muted);
  padding-bottom: 1.5rem;
  border-bottom: 1px solid var(--border);
}

/* ===== POST CONTENT ===== */
.post-content {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 2rem 2rem 4rem;
}

.post-content h1 {
  font-family: var(--font-display);
  font-size: 1.5rem;
  font-weight: 700;
  letter-spacing: 1px;
  color: #fff;
  margin: 2.5rem 0 1rem;
  padding-top: 1rem;
}

.post-content h2 {
  font-family: var(--font-display);
  font-size: 1.2rem;
  font-weight: 700;
  letter-spacing: 1px;
  color: #fff;
  margin: 2rem 0 .75rem;
}

.post-content h3, .post-content h4 {
  font-family: var(--font-display);
  font-size: 1rem;
  font-weight: 600;
  letter-spacing: .5px;
  color: var(--text);
  margin: 1.5rem 0 .5rem;
}

.post-content h5, .post-content h6 {
  font-family: var(--font-mono);
  font-size: .85rem;
  font-weight: 600;
  color: var(--accent);
  margin: 1.25rem 0 .5rem;
}

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

.post-content ul, .post-content ol {
  margin: .75rem 0 1rem 1.5rem;
  color: var(--text);
}

.post-content li { margin-bottom: .35rem; }

.post-content strong { color: #fff; font-weight: 600; }

.post-content hr {
  border: none;
  height: 1px;
  background: var(--border);
  margin: 2rem 0;
}

.post-content img {
  display: block;
  margin: 1.5rem auto;
  border: 1px solid var(--border);
  border-radius: 6px;
  box-shadow: 0 4px 20px rgba(0,0,0,.4);
}

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

.post-content a:hover {
  color: var(--accent-bright);
  text-decoration-color: var(--accent-bright);
}

/* code blocks */
.post-content code {
  font-family: var(--font-mono);
  font-size: .85em;
  background: var(--bg-code);
  color: var(--cyan);
  padding: 2px 6px;
  border-radius: 3px;
  border: 1px solid var(--border);
}

.post-content pre {
  background: var(--bg-code);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 1.25rem 1.5rem;
  margin: 1rem 0 1.5rem;
  overflow-x: auto;
  position: relative;
}

.post-content pre code {
  background: none;
  border: none;
  padding: 0;
  color: var(--text);
  font-size: .82rem;
  line-height: 1.65;
}

/* scrollbar */
.post-content pre::-webkit-scrollbar { height: 6px; }
.post-content pre::-webkit-scrollbar-track { background: var(--bg-code); }
.post-content pre::-webkit-scrollbar-thumb { background: var(--border); border-radius: 3px; }

.post-content blockquote {
  border-left: 3px solid var(--accent);
  padding: .75rem 1rem;
  margin: 1rem 0;
  background: rgba(0,232,123,.04);
  border-radius: 0 6px 6px 0;
  color: var(--text-muted);
}

/* ===== TABLE OF CONTENTS ===== */
.toc {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 1.25rem 1.5rem;
  margin-bottom: 2rem;
}

.toc-title {
  font-family: var(--font-mono);
  font-size: .75rem;
  color: var(--accent);
  letter-spacing: 2px;
  text-transform: uppercase;
  margin-bottom: .75rem;
}

.toc ul {
  list-style: none;
  margin: 0;
  padding: 0;
}

.toc li { margin-bottom: .3rem; }

.toc a {
  font-family: var(--font-mono);
  font-size: .8rem;
  color: var(--text-muted);
  transition: color .2s;
}

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

.toc .toc-h2 { padding-left: 0; }
.toc .toc-h3 { padding-left: 1rem; }
.toc .toc-h4 { padding-left: 2rem; }

/* ===== FOOTER ===== */
.site-footer {
  border-top: 1px solid var(--border);
  padding: 2rem;
  text-align: center;
  font-family: var(--font-mono);
  font-size: .75rem;
  color: var(--text-dim);
}

.site-footer a { color: var(--text-muted); }
.site-footer a:hover { color: var(--accent); }

.footer-links {
  display: flex;
  justify-content: center;
  gap: 1.5rem;
  margin-bottom: .75rem;
}

/* ===== 404 ===== */
.not-found {
  text-align: center;
  padding: 6rem 2rem;
}

.not-found h1 {
  font-family: var(--font-display);
  font-size: 5rem;
  color: var(--accent);
  letter-spacing: 5px;
}

.not-found p {
  font-family: var(--font-mono);
  color: var(--text-muted);
  margin-top: 1rem;
}

/* ===== CATEGORY FILTER ===== */
.category-filter {
  display: flex;
  flex-wrap: wrap;
  gap: .5rem;
  margin-bottom: 1.5rem;
}

.filter-btn {
  font-family: var(--font-mono);
  font-size: .75rem;
  letter-spacing: 1px;
  text-transform: uppercase;
  color: var(--text-muted);
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 5px;
  padding: 6px 14px;
  cursor: pointer;
  transition: all .2s;
}

.filter-btn:hover {
  color: var(--accent);
  border-color: var(--accent-dim);
  background: rgba(0,232,123,.06);
}

.filter-btn.active {
  color: var(--bg-deep);
  background: var(--accent);
  border-color: var(--accent);
  font-weight: 600;
}

/* ===== PAGINATION ===== */
.pagination {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 1rem;
  margin-top: 2rem;
  font-family: var(--font-mono);
  font-size: .8rem;
}

.pagination button {
  font-family: var(--font-mono);
  font-size: .8rem;
  color: var(--accent);
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 5px;
  padding: 8px 18px;
  cursor: pointer;
  transition: all .2s;
  letter-spacing: .5px;
}

.pagination button:hover:not(:disabled) {
  background: rgba(0,232,123,.1);
  border-color: var(--accent-dim);
}

.pagination button:disabled {
  opacity: .3;
  cursor: not-allowed;
}

.pagination .page-info {
  color: var(--text-dim);
}

.post-card.hidden {
  display: none;
}

/* ===== ANIMATIONS ===== */
@keyframes fadeUp {
  from { opacity: 0; transform: translateY(16px); }
  to { opacity: 1; transform: translateY(0); }
}

.animate-in {
  animation: fadeUp .5s ease both;
}

.post-card:nth-child(1) { animation-delay: .05s; }
.post-card:nth-child(2) { animation-delay: .1s; }
.post-card:nth-child(3) { animation-delay: .15s; }
.post-card:nth-child(4) { animation-delay: .2s; }
.post-card:nth-child(5) { animation-delay: .25s; }
.post-card:nth-child(6) { animation-delay: .3s; }

/* ===== RESPONSIVE ===== */
@media (max-width: 640px) {
  .site-header { padding: 0 1rem; }
  .site-nav { gap: .75rem; }
  .site-nav a { font-size: .7rem; }
  .hero { padding: 3rem 1.25rem 2.5rem; }
  .posts-section { padding: 0 1rem 3rem; }
  .post-header { padding: 2rem 1.25rem 1.5rem; }
  .post-content { padding: 1.5rem 1.25rem 3rem; }
  .post-card { padding: 1.25rem; }
  .post-card .meta { flex-wrap: wrap; gap: .5rem; }
}

/* Mobile hamburger */
.menu-toggle { display: none; background: none; border: none; cursor: pointer; padding: 4px; }
.menu-toggle span { display: block; width: 22px; height: 2px; background: var(--text-muted); margin: 5px 0; transition: .3s; }

@media (max-width: 480px) {
  .menu-toggle { display: block; }
  .site-nav {
    display: none;
    position: absolute;
    top: var(--header-height);
    right: 0;
    background: var(--bg-base);
    border: 1px solid var(--border);
    border-radius: 0 0 8px 8px;
    flex-direction: column;
    padding: 1rem 1.5rem;
    gap: 1rem;
  }
  .site-nav.open { display: flex; }
}