/* =====================================================
   Articles — shared stylesheet
   Per-article accent: override --ar, --ag, --ab, --article-accent in a
   tiny <style> block on each page (3 lines instead of ~120).
   ===================================================== */

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

:root {
  --bg:      #070d1a;
  --surface: #0d1526;
  --card:    #111e35;
  --border:  #1e2d4a;
  --accent:  #4f8ef7;
  --accent2: #06d6a0;
  --accent3: #f72585;
  --text:    #e8edf5;
  --muted:   #7a8aaa;
  --tag-bg:  #162040;
  --radius:  12px;
  /* per-article accent — default: blue */
  --ar: 79; --ag: 142; --ab: 247;
  --article-accent: var(--accent);
}

html { scroll-behavior: smooth; }
body { font-family: 'Inter', sans-serif; background: var(--bg); color: var(--text); line-height: 1.75; font-size: 16px; }

/* ── Nav ───────────────────────────────────────────── */
nav {
  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
  display: flex; align-items: center; justify-content: space-between;
  padding: 0 5vw; height: 64px;
  background: rgba(7,13,26,0.9); backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
}
.nav-logo { font-weight: 700; font-size: 1.05rem; color: var(--text); text-decoration: none; letter-spacing: -0.5px; }
.nav-logo span { color: var(--accent); }
.nav-back { display: flex; align-items: center; gap: 8px; color: var(--muted); font-size: 0.85rem; font-weight: 500; text-decoration: none; transition: color 0.2s; }
.nav-back:hover { color: var(--text); }

.lang-toggle {
  display: flex; align-items: center; gap: 6px;
  background: var(--tag-bg); border: 1px solid var(--border);
  color: var(--muted); font-size: 0.78rem; font-weight: 600;
  padding: 5px 12px; border-radius: 99px;
  cursor: pointer; transition: all 0.2s;
  font-family: 'Inter', sans-serif; letter-spacing: 0.3px;
}
.lang-toggle:hover { border-color: var(--accent); color: var(--accent); }

/* ── Hero ──────────────────────────────────────────── */
.hero-article {
  padding: 120px 5vw 60px;
  background: linear-gradient(180deg, rgba(var(--ar), var(--ag), var(--ab), 0.07) 0%, transparent 60%);
  border-bottom: 1px solid var(--border);
}
.hero-inner { max-width: 780px; margin: 0 auto; }

.article-category {
  display: inline-flex; align-items: center; gap: 6px;
  background: rgba(var(--ar), var(--ag), var(--ab), 0.1);
  border: 1px solid rgba(var(--ar), var(--ag), var(--ab), 0.25);
  color: var(--article-accent);
  font-size: 0.72rem; font-weight: 700;
  padding: 4px 12px; border-radius: 99px; letter-spacing: 1px;
  text-transform: uppercase; margin-bottom: 1.2rem;
}
.hero-article h1 {
  font-size: clamp(1.8rem, 4vw, 2.8rem); font-weight: 800;
  letter-spacing: -1px; line-height: 1.15; margin-bottom: 1rem;
}
.article-meta { display: flex; align-items: center; gap: 1.5rem; color: var(--muted); font-size: 0.82rem; flex-wrap: wrap; }
.article-meta span { display: flex; align-items: center; gap: 5px; }
.article-tags { display: flex; flex-wrap: wrap; gap: 6px; margin-top: 1.4rem; }
.tag { background: var(--tag-bg); border: 1px solid var(--border); color: var(--muted); font-size: 0.72rem; font-weight: 500; padding: 3px 10px; border-radius: 6px; font-family: 'JetBrains Mono', monospace; }

/* ── Article body ──────────────────────────────────── */
.article-content { max-width: 1280px; margin: 0 auto; padding: 20px 5vw 100px; }
.article-content h2 { font-size: 1.4rem; font-weight: 800; letter-spacing: -0.4px; margin: 2.5rem 0 1rem; color: var(--text); padding-bottom: 0.5rem; border-bottom: 1px solid var(--border); }
.article-content h3 { font-size: 1.05rem; font-weight: 700; margin: 1.8rem 0 0.7rem; color: var(--accent2); }
.article-content p { color: var(--muted); margin-bottom: 1.2rem; font-size: 0.97rem; }
.article-content strong { color: var(--text); }
.article-content ul, .article-content ol { margin: 0.5rem 0 1.2rem 1.5rem; }
.article-content li { color: var(--muted); font-size: 0.97rem; margin-bottom: 0.4rem; }
.article-content li strong { color: var(--text); }

/* ── Callout ───────────────────────────────────────── */
.callout { background: var(--card); border: 1px solid var(--border); border-left: 3px solid var(--accent); border-radius: 0 var(--radius) var(--radius) 0; padding: 1.2rem 1.4rem; margin: 1.5rem 0; }
.callout.green { border-left-color: var(--accent2); }
.callout.red   { border-left-color: var(--accent3); }
.callout p { margin: 0; font-size: 0.92rem; }

/* ── Code block ────────────────────────────────────── */
.code-block { background: var(--card); border: 1px solid var(--border); border-radius: var(--radius); padding: 1.3rem 1.5rem; margin: 1.2rem 0; overflow-x: auto; }
.code-block code { font-family: 'JetBrains Mono', monospace; font-size: 0.82rem; color: var(--accent2); line-height: 1.6; white-space: pre; }

/* ── Diagram (event-driven, microservices, scalable) ─ */
.diagram { background: var(--card); border: 1px solid var(--border); border-radius: var(--radius); padding: 1.5rem; margin: 1.5rem 0; text-align: center; }
.diagram-row, .diagram-nodes { display: flex; align-items: center; justify-content: center; gap: 0.7rem; flex-wrap: wrap; margin: 0.5rem 0; }
.d-node, .node {
  background: var(--tag-bg); border: 1px solid var(--border);
  border-radius: 8px; padding: 0.6rem 1rem;
  font-family: 'JetBrains Mono', monospace; font-size: 0.8rem; font-weight: 500; text-align: center;
}
.d-node.blue,  .node.accent { border-color: rgba(79,142,247,0.4);  color: var(--accent); }
.d-node.green, .node.green  { border-color: rgba(6,214,160,0.4);   color: var(--accent2); }
.d-node.red,   .node.red    { border-color: rgba(247,37,133,0.4);  color: var(--accent3); }
.d-arrow { color: var(--muted); font-size: 1.1rem; }
.arrow   { color: var(--muted); font-size: 1.3rem; display: flex; align-items: center; }
.diagram-label { font-size: 0.72rem; color: var(--muted); margin-top: 0.8rem; text-align: center; font-style: italic; }

/* ── Pipeline (data-pipelines, mlops, cicd) ─────────── */
.pipeline { background: var(--card); border: 1px solid var(--border); border-radius: var(--radius); padding: 1.5rem; margin: 1.5rem 0; }
.pipeline-steps { display: flex; align-items: center; flex-wrap: wrap; gap: 0.5rem; }
.pipeline-step { background: var(--tag-bg); border: 1px solid var(--border); border-radius: 8px; padding: 0.6rem 1rem; font-size: 0.8rem; font-weight: 600; font-family: 'JetBrains Mono', monospace; color: var(--text); text-align: center; }
.pipeline-step.active, .pipeline-step.green { border-color: rgba(6,214,160,0.4);  color: var(--accent2); }
.pipeline-step.warn                          { border-color: rgba(244,162,97,0.4); color: #f4a261; }
.pipeline-step.blue                          { border-color: rgba(79,142,247,0.4); color: var(--accent); }
.pipeline-step.red                           { border-color: rgba(247,37,133,0.4); color: var(--accent3); }
.pipeline-arrow { color: var(--muted); font-size: 1rem; }
.pipeline-label { font-size: 0.72rem; color: var(--muted); margin-top: 0.8rem; font-style: italic; }

/* ── Compare grid (microservices) ──────────────────── */
.compare-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 1rem; margin: 1.5rem 0; }
.compare-card { background: var(--card); border: 1px solid var(--border); border-radius: var(--radius); padding: 1.3rem; }
.compare-card h4 { font-size: 0.85rem; font-weight: 700; margin-bottom: 0.8rem; }
.compare-card h4.blue  { color: var(--accent); }
.compare-card h4.green { color: var(--accent2); }
.compare-card ul { margin-left: 1rem; }
.compare-card li { font-size: 0.82rem; color: var(--muted); margin-bottom: 0.3rem; }
@media (max-width: 600px) { .compare-grid { grid-template-columns: 1fr; } }

/* ── HTTP method grid (api-design) ─────────────────── */
.http-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(160px, 1fr)); gap: 0.8rem; margin: 1.2rem 0; }
.http-card { background: var(--card); border: 1px solid var(--border); border-radius: 8px; padding: 0.9rem 1rem; }
.http-method { font-family: 'JetBrains Mono', monospace; font-size: 0.78rem; font-weight: 700; margin-bottom: 4px; }
.http-method.get    { color: #06d6a0; }
.http-method.post   { color: #4f8ef7; }
.http-method.put    { color: #f4a261; }
.http-method.patch  { color: #a78bfa; }
.http-method.delete { color: #f72585; }
.http-desc { font-size: 0.75rem; color: var(--muted); }

/* ── Metrics grid (model-monitoring) ───────────────── */
.metrics-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(180px, 1fr)); gap: 1rem; margin: 1.5rem 0; }
.metric-card  { background: var(--card); border: 1px solid var(--border); border-radius: var(--radius); padding: 1.2rem; }
.metric-label { font-size: 0.72rem; font-weight: 700; color: var(--muted); text-transform: uppercase; letter-spacing: 0.5px; margin-bottom: 0.4rem; }
.metric-value { font-size: 1.6rem; font-weight: 800; color: var(--accent2); font-family: 'JetBrains Mono', monospace; }
.metric-value.warn   { color: #f4a261; }
.metric-value.danger { color: var(--accent3); }
.metric-desc  { font-size: 0.72rem; color: var(--muted); margin-top: 4px; }

/* ── Hexagonal architecture (hexagonal) ─────────────── */
.hex-ring    { display: flex; align-items: center; justify-content: center; gap: 1rem; flex-wrap: wrap; }
.hex-box     { border-radius: 10px; padding: 0.7rem 1.2rem; font-family: 'JetBrains Mono', monospace; font-size: 0.78rem; font-weight: 600; text-align: center; border: 1px solid; }
.hex-core    { background: rgba(79,142,247,0.15); border-color: rgba(79,142,247,0.4); color: var(--accent); font-size: 0.9rem; padding: 1rem 2rem; }
.hex-port    { background: rgba(6,214,160,0.1);   border-color: rgba(6,214,160,0.3);  color: var(--accent2); }
.hex-adapter { background: var(--tag-bg); border-color: var(--border); color: var(--muted); }

/* ── Footer ────────────────────────────────────────── */
.article-footer { max-width: 780px; margin: 0 auto; padding: 2rem 5vw 60px; border-top: 1px solid var(--border); }
.back-link { display: inline-flex; align-items: center; gap: 8px; color: var(--accent); font-size: 0.87rem; font-weight: 600; text-decoration: none; transition: gap 0.2s; }
.back-link:hover { gap: 12px; }
footer { text-align: center; padding: 2rem; color: var(--muted); font-size: 0.8rem; border-top: 1px solid var(--border); }