:root {
  --bg: #0f1113;
  --panel: #191d21;
  --panel-2: #21262b;
  --text: #e8e6e3;
  --muted: #9aa0a6;
  --accent: #e8611c;
  --accent-soft: rgba(232, 97, 28, 0.14);
  --border: #2c3237;
  --radius: 12px;
}
* { box-sizing: border-box; margin: 0; padding: 0; }
body {
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  line-height: 1.6;
}
.site-header {
  padding: 2rem 1.25rem 1rem;
  max-width: 720px;
  margin: 0 auto;
}
.brand {
  font-size: 1.75rem;
  font-weight: 800;
  color: var(--text);
  text-decoration: none;
  letter-spacing: -0.02em;
}
.brand::after { content: "."; color: var(--accent); }
.tagline { color: var(--muted); margin-top: 0.25rem; }
main { max-width: 720px; margin: 0 auto; padding: 0 1.25rem 3rem; }
.site-footer {
  max-width: 720px;
  margin: 0 auto;
  padding: 1.5rem 1.25rem 2.5rem;
  color: var(--muted);
  font-size: 0.875rem;
  border-top: 1px solid var(--border);
}

/* Library */
.section-title { font-size: 1.1rem; margin: 1.5rem 0 0.75rem; color: var(--muted); text-transform: uppercase; letter-spacing: 0.08em; font-size: 0.8rem; }
.card-grid { display: grid; gap: 0.9rem; }
.card {
  display: block;
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.1rem 1.25rem;
  text-decoration: none;
  color: var(--text);
  transition: border-color 0.15s ease, transform 0.15s ease;
}
.card:hover { border-color: var(--accent); transform: translateY(-2px); }
.card-category {
  display: inline-block;
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--accent);
  background: var(--accent-soft);
  padding: 0.15rem 0.55rem;
  border-radius: 999px;
  margin-bottom: 0.5rem;
}
.card-title { font-size: 1.15rem; font-weight: 700; }
.card-meta { color: var(--muted); font-size: 0.85rem; margin-top: 0.35rem; }

/* Topic detail */
.back-link {
  display: inline-block;
  color: var(--muted);
  text-decoration: none;
  margin: 1rem 0;
  font-size: 0.9rem;
}
.back-link:hover { color: var(--accent); }
.topic-head { margin-bottom: 1.25rem; }
.topic-title { font-size: 1.6rem; font-weight: 800; letter-spacing: -0.01em; }
.fact-strip {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
  gap: 0.6rem;
  margin: 1rem 0 1.5rem;
}
.fact {
  background: var(--panel-2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 0.7rem 0.85rem;
}
.fact-label { font-size: 0.7rem; text-transform: uppercase; letter-spacing: 0.08em; color: var(--muted); }
.fact-value { font-size: 0.9rem; margin-top: 0.2rem; }
.block {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.25rem;
  margin-bottom: 1rem;
}
.block--why { border-left: 3px solid var(--accent); }
.block-title { font-size: 1.05rem; font-weight: 700; margin-bottom: 0.6rem; }
.block-title .hint { color: var(--accent); font-size: 0.75rem; text-transform: uppercase; letter-spacing: 0.08em; margin-left: 0.5rem; }
.block p + p { margin-top: 0.7rem; }
.block ol, .block ul { padding-left: 1.4rem; }
.block li { margin-bottom: 0.55rem; }
.block li::marker { color: var(--accent); font-weight: 700; }
.tools-list { display: flex; flex-wrap: wrap; gap: 0.5rem; list-style: none; padding-left: 0 !important; }
.tools-list li {
  background: var(--panel-2);
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 0.3rem 0.8rem;
  font-size: 0.85rem;
  margin-bottom: 0;
}
.video-link { color: var(--accent); }
.source-note { color: var(--muted); font-size: 0.8rem; margin-top: 0.5rem; }
.loading, .error { color: var(--muted); padding: 2rem 0; text-align: center; }
.scope-note { color:var(--text); padding:1rem; border:1px solid var(--accent); border-radius:var(--radius); background:var(--accent-soft); margin:1rem 0; }
.stop { border-left:3px solid #f2a65a; }
.checklist { list-style:none; padding-left:0!important; }
.checklist li { margin:0; border-bottom:1px solid var(--border); }
.checklist label { display:flex; gap:.75rem; padding:.8rem 0; cursor:pointer; }
.checklist input { width:22px; height:22px; flex:none; accent-color:var(--accent); }
.block input[type=number], .block textarea { display:block; width:100%; background:var(--panel-2); border:1px solid var(--border); border-radius:7px; color:var(--text); padding:.7rem; margin:.35rem 0 1rem; font:inherit; }
.block label { display:block; }
.block button { background:var(--accent); color:#101010; font-weight:700; border:0; border-radius:7px; padding:.7rem 1rem; cursor:pointer; margin:.7rem 0; }
.block button:disabled { opacity:.5; cursor:default; }
#log-status { color:var(--muted); }


/* subsystem + boundary + symptom + planned (dev merge additions) */
.symptom { color: var(--muted); margin: 0.5rem 0 1rem; }
.planned-row { display: flex; flex-wrap: wrap; gap: 0.5rem; margin-bottom: 0.5rem; }
.planned-pill {
  background: var(--panel-2);
  border: 1px dashed var(--border);
  color: var(--muted);
  border-radius: 999px;
  padding: 0.3rem 0.8rem;
  font-size: 0.85rem;
}
.boundary-grid { display: grid; grid-template-columns: 1fr; gap: 1rem; }
@media (min-width: 560px) { .boundary-grid { grid-template-columns: 1fr 1fr; } }
.boundary-title { font-size: 0.85rem; text-transform: uppercase; letter-spacing: 0.08em; margin-bottom: 0.4rem; }
.boundary-diy { color: #6fbf73; }
.boundary-service { color: #f2a65a; }