/* ============================================================
   XTHOR BLOG — Design System (extends website tokens)
   ============================================================ */

/* ── Tokens ─────────────────────────────────────────────── */
:root {
  --bg:    #030b12;
  --bg-1:  #06101a;
  --bg-2:  #0a1723;
  --bg-3:  #0f1f2e;

  --border:    rgba(180, 195, 210, 0.07);
  --border-md: rgba(180, 195, 210, 0.12);
  --border-lg: rgba(180, 195, 210, 0.20);

  --blue:        #c47820;
  --blue-bright: #e09535;
  --blue-dim:    #7a4c12;
  --blue-bg:     rgba(196, 120, 32, 0.08);
  --blue-glow:   rgba(196, 120, 32, 0.16);

  --steel:     #3e7a9a;
  --steel-dim: rgba(62, 122, 154, 0.08);

  --amber:       #e07820;
  --red:         #d63535;
  --red-dim:     rgba(214, 53, 53, 0.10);
  --green:       #25a05a;
  --green-dim:   rgba(37, 160, 90, 0.10);

  --text:   #dce8f2;
  --text-2: #7a96ae;
  --text-3: #3e5a6e;

  --font: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  --mono: 'JetBrains Mono', 'Fira Code', ui-monospace, monospace;

  --ease:     cubic-bezier(0.16, 1, 0.3, 1);
  --ease-std: cubic-bezier(0.4, 0, 0.2, 1);

  --r-sm:  4px;
  --r-md:  8px;
  --r-lg:  12px;
  --r-xl:  18px;
  --r-2xl: 24px;
}

/* ── Reset ───────────────────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; font-size: 16px; }
body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}
a { color: inherit; text-decoration: none; }
img, svg { display: block; }
button { font-family: inherit; cursor: pointer; }
ul { list-style: none; }

/* ── Typography helpers ──────────────────────────────────── */
.t-overline {
  font-size: 10.5px;
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--blue-bright);
}

/* ── Layout ──────────────────────────────────────────────── */
.container {
  max-width: 1180px;
  margin: 0 auto;
  padding: 0 32px;
}
.container-narrow {
  max-width: 760px;
  margin: 0 auto;
  padding: 0 32px;
}

/* ── Buttons ─────────────────────────────────────────────── */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 0.875rem;
  font-weight: 600;
  border-radius: var(--r-md);
  padding: 10px 20px;
  border: none;
  transition: all 0.18s var(--ease-std);
  white-space: nowrap;
}
.btn-primary {
  background: var(--blue);
  color: #fff;
}
.btn-primary:hover { background: var(--blue-bright); }
.btn-sm { padding: 7px 16px; font-size: 0.8rem; }

/* ── Nav ─────────────────────────────────────────────────── */
.nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 100;
  padding: 16px 0;
  transition: background 0.25s, border-color 0.25s, padding 0.25s;
  border-bottom: 1px solid transparent;
}
.nav.scrolled {
  background: rgba(3, 11, 18, 0.92);
  backdrop-filter: blur(12px);
  border-color: var(--border);
  padding: 12px 0;
}
.nav-inner {
  max-width: 1180px;
  margin: 0 auto;
  padding: 0 32px;
  display: flex;
  align-items: center;
  gap: 40px;
}
.nav-logo {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-shrink: 0;
}
.logo-mark {
  width: 28px; height: 28px;
  background: var(--blue);
  border-radius: var(--r-sm);
  display: flex; align-items: center; justify-content: center;
  font-size: 0.875rem;
  font-weight: 900;
  color: #fff;
  letter-spacing: -0.02em;
}
.logo-name {
  font-size: 1rem;
  font-weight: 800;
  letter-spacing: -0.02em;
  color: var(--text);
}
.nav-links {
  display: flex;
  align-items: center;
  gap: 28px;
  margin-right: auto;
}
.nav-links a {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-2);
  transition: color 0.15s;
}
.nav-links a:hover,
.nav-links a.active { color: var(--text); }

/* ── Blog hero ───────────────────────────────────────────── */
.blog-hero {
  padding: 140px 0 72px;
  position: relative;
  border-bottom: 1px solid var(--border);
}
.blog-hero::before {
  content: '';
  position: absolute;
  top: 0; left: 50%;
  transform: translateX(-50%);
  width: 700px; height: 300px;
  background: radial-gradient(ellipse at 50% 0%, rgba(196, 120, 32, 0.10) 0%, transparent 70%);
  pointer-events: none;
}
.blog-hero-title {
  font-size: clamp(2.2rem, 5vw, 3.5rem);
  font-weight: 800;
  letter-spacing: -0.03em;
  color: var(--text);
  margin-top: 12px;
  line-height: 1.1;
}
.blog-hero-sub {
  font-size: 1.05rem;
  color: var(--text-2);
  margin-top: 16px;
  max-width: 540px;
}

/* ── Filter bar ──────────────────────────────────────────── */
.filter-bar {
  position: sticky;
  top: 57px;
  z-index: 50;
  background: rgba(3, 11, 18, 0.88);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
  padding: 14px 0;
}
.filter-bar .container {
  display: flex;
  align-items: center;
  gap: 16px;
  flex-wrap: wrap;
}
.filter-tags {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
  flex: 1;
}
.filter-tag {
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  padding: 5px 12px;
  border-radius: 100px;
  border: 1px solid var(--border-md);
  background: transparent;
  color: var(--text-2);
  transition: all 0.15s;
}
.filter-tag:hover {
  border-color: var(--blue);
  color: var(--blue-bright);
}
.filter-tag.active {
  background: var(--blue-bg);
  border-color: var(--blue);
  color: var(--blue-bright);
}
.filter-search-wrap {
  display: flex;
  align-items: center;
  gap: 8px;
  background: var(--bg-2);
  border: 1px solid var(--border-md);
  border-radius: var(--r-md);
  padding: 7px 12px;
  color: var(--text-3);
}
.filter-search {
  background: none;
  border: none;
  outline: none;
  font-family: var(--font);
  font-size: 0.825rem;
  color: var(--text);
  width: 180px;
}
.filter-search::placeholder { color: var(--text-3); }

/* ── Blog main / grid ────────────────────────────────────── */
.blog-main {
  padding: 56px 0 96px;
  min-height: 60vh;
}
.posts-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}
.posts-grid--related {
  grid-template-columns: repeat(3, 1fr);
}

/* ── Post card ───────────────────────────────────────────── */
.post-card {
  background: var(--bg-1);
  border: 1px solid var(--border);
  border-radius: var(--r-xl);
  padding: 28px;
  display: flex;
  flex-direction: column;
  gap: 12px;
  cursor: pointer;
  transition: border-color 0.2s, background 0.2s, transform 0.2s var(--ease);
  text-decoration: none;
  color: inherit;
  opacity: 0;
  transform: translateY(12px);
}
.post-card.visible {
  opacity: 1;
  transform: none;
}
.post-card:hover {
  border-color: var(--border-lg);
  background: var(--bg-2);
  transform: translateY(-2px);
}
.post-card--featured {
  grid-column: span 2;
  flex-direction: row;
  align-items: flex-start;
  gap: 28px;
}
.post-card--featured .card-cover {
  flex-shrink: 0;
  width: 240px;
  height: 100%;
  min-height: 160px;
}
.card-cover {
  width: 100%;
  height: 160px;
  border-radius: var(--r-md);
  background: var(--bg-3);
  overflow: hidden;
  position: relative;
}
.card-cover-inner {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 2.5rem;
  opacity: 0.4;
}
.card-cover-gradient {
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, var(--blue-bg) 0%, transparent 60%);
}
.card-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}
.card-tag {
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  padding: 3px 8px;
  border-radius: 100px;
  background: var(--blue-bg);
  border: 1px solid var(--blue-dim);
  color: var(--blue-bright);
}
.card-tag--steel {
  background: var(--steel-dim);
  border-color: rgba(62, 122, 154, 0.3);
  color: var(--steel);
}
.card-tag--red {
  background: var(--red-dim);
  border-color: rgba(214, 53, 53, 0.3);
  color: #e06060;
}
.card-tag--green {
  background: var(--green-dim);
  border-color: rgba(37, 160, 90, 0.3);
  color: #40c07a;
}
.card-body { flex: 1; display: flex; flex-direction: column; gap: 8px; }
.card-title {
  font-size: 1rem;
  font-weight: 700;
  line-height: 1.35;
  color: var(--text);
  transition: color 0.15s;
}
.post-card:hover .card-title { color: var(--blue-bright); }
.card-excerpt {
  font-size: 0.855rem;
  color: var(--text-2);
  line-height: 1.6;
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
}
.card-meta {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.75rem;
  color: var(--text-3);
  margin-top: auto;
  padding-top: 12px;
  border-top: 1px solid var(--border);
}
.card-author-avatar {
  width: 22px; height: 22px;
  border-radius: 50%;
  background: var(--blue-bg);
  border: 1px solid var(--blue-dim);
  display: flex; align-items: center; justify-content: center;
  font-size: 0.65rem;
  font-weight: 700;
  color: var(--blue-bright);
  flex-shrink: 0;
}
.meta-sep { color: var(--text-3); opacity: 0.5; }
.card-read { font-family: var(--mono); font-size: 0.7rem; }

/* ── Empty state ──────────────────────────────────────────── */
.posts-empty {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 16px;
  padding: 96px 0;
  color: var(--text-2);
  font-size: 0.9rem;
}

/* ── Article layout ──────────────────────────────────────── */
.article-layout {
  padding-top: 57px;
  min-height: 100vh;
}
.article-topbar {
  padding: 20px 0;
  border-bottom: 1px solid var(--border);
}
.back-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 0.825rem;
  font-weight: 500;
  color: var(--text-2);
  transition: color 0.15s;
}
.back-link:hover { color: var(--blue-bright); }
.article-header {
  padding: 64px 0 52px;
  border-bottom: 1px solid var(--border);
  position: relative;
}
.article-header::before {
  content: '';
  position: absolute;
  top: 0; left: 50%;
  transform: translateX(-50%);
  width: 600px; height: 250px;
  background: radial-gradient(ellipse at 50% 0%, rgba(196,120,32,0.08) 0%, transparent 70%);
  pointer-events: none;
}
.article-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-bottom: 20px;
}
.article-title {
  font-size: clamp(1.8rem, 4vw, 2.75rem);
  font-weight: 800;
  letter-spacing: -0.03em;
  color: var(--text);
  line-height: 1.15;
  margin-bottom: 18px;
}
.article-excerpt {
  font-size: 1.1rem;
  color: var(--text-2);
  line-height: 1.65;
  margin-bottom: 28px;
}
.article-meta {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.8rem;
  color: var(--text-3);
}
.article-author { color: var(--text-2); font-weight: 500; }

/* ── Skeleton loader ──────────────────────────────────────── */
.skeleton-wrap { display: flex; flex-direction: column; gap: 12px; padding: 56px 0; }
.skeleton-line {
  height: 14px;
  border-radius: var(--r-sm);
  background: linear-gradient(90deg, var(--bg-2) 0%, var(--bg-3) 50%, var(--bg-2) 100%);
  background-size: 200% 100%;
  animation: shimmer 1.4s infinite;
}
@keyframes shimmer {
  0%   { background-position: 200% 0; }
  100% { background-position: -200% 0; }
}

/* ── Prose (article body) ────────────────────────────────── */
.article-body-wrap { padding: 56px 0; }
.prose {
  font-size: 1rem;
  line-height: 1.8;
  color: var(--text);
}
.prose h1,
.prose h2,
.prose h3,
.prose h4 {
  color: var(--text);
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-top: 2.2em;
  margin-bottom: 0.6em;
  line-height: 1.25;
}
.prose h1 { font-size: 1.9rem; }
.prose h2 {
  font-size: 1.45rem;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--border);
}
.prose h3 { font-size: 1.2rem; color: var(--blue-bright); }
.prose h4 { font-size: 1rem; font-weight: 600; }
.prose p { margin-bottom: 1.4em; }
.prose strong { color: var(--text); font-weight: 700; }
.prose em { color: var(--text-2); }
.prose a { color: var(--blue-bright); border-bottom: 1px solid var(--blue-dim); transition: color 0.15s; }
.prose a:hover { color: var(--blue); }
.prose ul,
.prose ol {
  padding-left: 1.5em;
  margin-bottom: 1.4em;
  list-style: revert;
}
.prose li { margin-bottom: 0.4em; color: var(--text); }
.prose blockquote {
  border-left: 3px solid var(--blue);
  padding: 12px 20px;
  background: var(--blue-bg);
  border-radius: 0 var(--r-md) var(--r-md) 0;
  margin: 1.8em 0;
}
.prose blockquote p { margin: 0; color: var(--text-2); font-style: italic; }
.prose code {
  font-family: var(--mono);
  font-size: 0.85em;
  background: var(--bg-2);
  border: 1px solid var(--border-md);
  border-radius: var(--r-sm);
  padding: 2px 6px;
  color: var(--blue-bright);
}
.prose pre {
  background: var(--bg-1);
  border: 1px solid var(--border-md);
  border-radius: var(--r-lg);
  padding: 20px 24px;
  overflow-x: auto;
  margin: 1.8em 0;
}
.prose pre code {
  background: none;
  border: none;
  padding: 0;
  font-size: 0.875rem;
  color: var(--text);
}
.prose table {
  width: 100%;
  border-collapse: collapse;
  margin: 1.8em 0;
  font-size: 0.875rem;
}
.prose th {
  background: var(--bg-2);
  color: var(--text-2);
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  padding: 10px 14px;
  border-bottom: 2px solid var(--border-md);
  text-align: left;
}
.prose td {
  padding: 10px 14px;
  border-bottom: 1px solid var(--border);
  color: var(--text);
}
.prose tr:hover td { background: var(--bg-1); }
.prose hr {
  border: none;
  border-top: 1px solid var(--border-md);
  margin: 2.4em 0;
}
.prose img {
  max-width: 100%;
  border-radius: var(--r-lg);
  border: 1px solid var(--border);
  margin: 1.8em 0;
}

/* highlight.js overrides */
.hljs { background: transparent !important; }

/* ── Article error ───────────────────────────────────────── */
.article-error {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 16px;
  padding: 80px 0;
  text-align: center;
}
.article-error h3 { font-size: 1.2rem; color: var(--text); }
.article-error p { color: var(--text-2); }
.article-error a { color: var(--blue-bright); }

/* ── Related articles ────────────────────────────────────── */
.related-wrap {
  border-top: 1px solid var(--border);
  padding: 56px 0 80px;
}

/* Raw markdown fallback (when marked/highlight CDN is blocked) */
.md-raw {
  font-family: var(--mono);
  font-size: 0.9rem;
  white-space: pre-wrap;
  word-break: break-word;
  background: var(--bg-1);
  border: 1px solid var(--border-md);
  border-radius: var(--r-lg);
  padding: 20px 24px;
  margin: 0;
}

/* ── Footer ──────────────────────────────────────────────── */
.blog-footer {
  border-top: 1px solid var(--border);
  padding: 28px 0;
}
.blog-footer .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.footer-left {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 0.8rem;
  color: var(--text-3);
}
.footer-name { font-weight: 700; color: var(--text-2); }
.footer-copy { color: var(--text-3); }
.footer-right a {
  font-size: 0.8rem;
  color: var(--text-3);
  transition: color 0.15s;
}
.footer-right a:hover { color: var(--blue-bright); }

/* ── Responsive ──────────────────────────────────────────── */
@media (max-width: 1024px) {
  .posts-grid { grid-template-columns: repeat(2, 1fr); }
  .post-card--featured { grid-column: span 2; }
}
@media (max-width: 768px) {
  .container, .container-narrow { padding: 0 20px; }
  .posts-grid { grid-template-columns: 1fr; }
  .post-card--featured { flex-direction: column; }
  .post-card--featured .card-cover { width: 100%; height: 160px; }
  .nav-links { display: none; }
  .filter-search { width: 120px; }
  .blog-hero { padding: 110px 0 48px; }
}
@media (max-width: 520px) {
  .posts-grid--related { grid-template-columns: 1fr; }
}