:root {
  --bg: #05070c;
  --panel: rgba(10, 16, 32, 0.9);
  --border: rgba(88, 166, 255, 0.2);
  --border-hover: rgba(88, 166, 255, 0.45);
  --text: #e6edf3;
  --muted: #8b949e;
  --accent: #58a6ff;
  --green: #3fb950;
  --purple: #a371f7;
  --yellow: #e3b341;
  --glow: rgba(88, 166, 255, 0.3);
}

body.light {
  --bg: #b8c4d4;
  --border: rgba(60, 80, 120, 0.2);
  --border-hover: rgba(60, 80, 120, 0.5);
  --text: #0d1117;
  --muted: #3d4a5c;
  --accent: #0969da;
  --green: #1a7f37;
  --purple: #6e40c9;
  --glow: rgba(9, 105, 218, 0.15);
}

body.light {
  background: radial-gradient(ellipse at 20% 10%, #a8b8cc, #b8c4d4 60%);
}

body.light .post-card {
  background: rgba(155, 170, 195, 0.6);
  box-shadow: 0 2px 16px rgba(0,0,0,0.12);
}

body.light .filters button {
  background: rgba(0,0,0,0.07);
}

body.light .post-search {
  background: rgba(0,0,0,0.07);
}

body.light .back-nav a { color: var(--muted); }

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

body {
  background: radial-gradient(circle at 20% 10%, #0b1225, #05070c 60%);
  color: var(--text);
  font-family: 'Inter', sans-serif;
  min-height: 100vh;
}

/* ================= BACK LINK ================= */
.back-nav {
  max-width: 1100px;
  margin: 0 auto;
  padding: 28px 24px 0;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.back-nav a {
  font-size: 13px;
  color: var(--muted);
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  transition: color 0.2s ease;
}

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

.posts-theme-toggle {
  width: 34px;
  height: 34px;
  border-radius: 8px;
  background: rgba(88,166,255,0.08);
  border: 1px solid var(--border);
  cursor: pointer;
  font-size: 15px;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all 0.2s ease;
}

.posts-theme-toggle:hover {
  border-color: var(--border-hover);
  box-shadow: 0 0 12px var(--glow);
}

/* ================= SCROLLBAR ================= */
::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb {
  background: linear-gradient(to bottom, #58a6ff, #a371f7);
  border-radius: 999px;
}
* { scrollbar-width: thin; scrollbar-color: #58a6ff transparent; }
body.light * { scrollbar-color: #0969da transparent; }

/* ================= EYEBROW ================= */
.posts-eyebrow {
  font-family: 'JetBrains Mono', monospace;
  font-size: 11px;
  letter-spacing: 3px;
  color: var(--accent);
  text-transform: uppercase;
  margin-bottom: 12px;
  opacity: 0.8;
}

/* ================= HEADER ================= */
.posts-header {
  max-width: 1100px;
  margin: 48px auto 40px;
  padding: 0 24px;
}

.posts-header h1 {
  font-size: 42px;
  font-weight: 700;
  letter-spacing: -1px;
}

.posts-header p {
  color: var(--muted);
  margin-top: 8px;
  font-size: 15px;
}

/* ================= FILTERS ================= */
.filters {
  display: flex;
  gap: 8px;
  margin-top: 24px;
  flex-wrap: wrap;
}

.filters button {
  padding: 7px 16px;
  border-radius: 999px;
  font-size: 12px;
  font-weight: 500;
  border: 1px solid var(--border);
  background: rgba(255, 255, 255, 0.04);
  color: var(--muted);
  cursor: pointer;
  transition: all 0.2s ease;
  font-family: 'Inter', sans-serif;
}

.filters button.active,
.filters button:hover {
  background: rgba(88, 166, 255, 0.12);
  border-color: var(--border-hover);
  color: var(--text);
  box-shadow: 0 0 16px var(--glow);
}

/* ================= SEARCH ================= */
.post-search {
  margin-top: 16px;
  width: 100%;
  max-width: 380px;
  padding: 10px 16px;
  border-radius: 10px;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid var(--border);
  color: var(--text);
  font-size: 14px;
  font-family: 'Inter', sans-serif;
  transition: all 0.2s ease;
}

.post-search::placeholder { color: var(--muted); }

.post-search:focus {
  outline: none;
  border-color: var(--border-hover);
  box-shadow: 0 0 20px var(--glow);
  background: rgba(255, 255, 255, 0.07);
}

/* ================= GRID ================= */
.posts-container {
  max-width: 1100px;
  margin: auto;
  padding: 0 24px 120px;
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 24px;
}

/* ================= CARD ================= */
.post-card {
  background: rgba(10, 16, 32, 0.85);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 24px;
  text-decoration: none;
  color: var(--text);
  transition: all 0.25s ease;
  display: flex;
  flex-direction: column;
  position: relative;
  overflow: hidden;
  min-height: 180px;
}

.post-card::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--accent), var(--purple));
  opacity: 0;
  transition: opacity 0.3s ease;
}

.post-card:hover {
  transform: translateY(-5px);
  border-color: var(--border-hover);
  box-shadow: 0 24px 80px rgba(0,0,0,0.5), 0 0 30px var(--glow);
}

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

/* type tag */
.post-type {
  display: inline-block;
  font-family: 'JetBrains Mono', monospace;
  font-size: 10px;
  font-weight: 600;
  padding: 3px 10px;
  border-radius: 999px;
  border: 1px solid var(--border);
  color: var(--accent);
  background: rgba(88, 166, 255, 0.1);
  letter-spacing: 0.5px;
  text-transform: uppercase;
}

.post-type.research {
  color: var(--accent);
  background: rgba(88, 166, 255, 0.1);
  border-color: rgba(88, 166, 255, 0.25);
}

.post-type.writeup {
  color: var(--green);
  background: rgba(63, 185, 80, 0.1);
  border-color: rgba(63, 185, 80, 0.25);
}

.post-type.notes {
  color: var(--purple);
  background: rgba(163, 113, 247, 0.1);
  border-color: rgba(163, 113, 247, 0.25);
}

/* title */
.post-card h3 {
  margin-top: 12px;
  font-size: 16px;
  font-weight: 600;
  line-height: 1.4;
}

/* description */
.post-desc {
  margin-top: 8px;
  font-size: 13px;
  color: var(--muted);
  line-height: 1.6;
  flex: 1;
}

/* footer */
.post-meta {
  margin-top: 16px;
  font-size: 11px;
  font-family: 'JetBrains Mono', monospace;
  color: var(--muted);
  display: flex;
  justify-content: space-between;
  padding-top: 12px;
  border-top: 1px solid var(--border);
}

/* empty state */
.posts-empty {
  grid-column: 1 / -1;
  text-align: center;
  padding: 80px 0;
  color: var(--muted);
  font-size: 15px;
}

/* ================= MOBILE ================= */
@media (max-width: 768px) {
  .posts-header {
    margin-top: 48px;
  }

  .posts-header h1 {
    font-size: 32px;
  }

  .posts-container {
    grid-template-columns: 1fr;
  }
}