/* ===== MFMF course site — component styles ===== */

:root {
  --ink:#0F1E3D; --ink-soft:#1B2E52; --parchment:#F7F4ED; --paper:#FDFCF9;
  --brass:#B4884A; --brass-deep:#8F6A34; --slate:#5A6B82; --slate-soft:#8A97A8;
  --cite:#2C5AA0; --line:#DCD6C8;
}

/* ---------- HERO ---------- */
.hero {
  margin: 0 0 2.4rem; padding: 2.8rem 0 2.2rem;
  border-bottom: 1px solid var(--line);
}
.hero .eyebrow {
  font-family: "Inter", sans-serif; text-transform: uppercase;
  letter-spacing: 0.18em; font-size: 0.72rem; font-weight: 600;
  color: var(--brass-deep); margin-bottom: 1rem;
}
.hero h1.title {
  font-family: "Spectral", serif; font-weight: 700; line-height: 1.08;
  font-size: clamp(2.1rem, 5vw, 3.3rem); letter-spacing: -0.02em;
  color: var(--ink); margin: 0 0 1rem;
}
.hero .lede {
  font-size: 1.16rem; line-height: 1.55; color: #3a4048; max-width: 44rem;
}
.hero .cta-row { margin-top: 1.8rem; display: flex; gap: 0.8rem; flex-wrap: wrap; }
.btn-lab {
  background: var(--ink); color: #fff !important; border: 1px solid var(--ink);
  padding: 0.65rem 1.4rem; border-radius: 2px; font-family: "Inter", sans-serif;
  font-weight: 600; font-size: 0.95rem; text-decoration: none !important;
  transition: all 0.15s ease;
}
.btn-lab:hover { background: var(--brass); border-color: var(--brass); color: var(--ink) !important; }
.btn-ghost {
  background: transparent; color: var(--ink) !important; border: 1px solid var(--slate);
  padding: 0.65rem 1.4rem; border-radius: 2px; font-family: "Inter", sans-serif;
  font-weight: 600; font-size: 0.95rem; text-decoration: none !important;
}
.btn-ghost:hover { border-color: var(--brass-deep); color: var(--brass-deep) !important; }

/* ---------- PRIMITIVE SPINE (signature element) ---------- */
.spine { margin: 2.6rem 0; }
.spine .spine-label {
  font-family:"Inter",sans-serif; font-size:0.72rem; letter-spacing:0.16em;
  text-transform:uppercase; color:var(--slate); margin-bottom:0.9rem;
}
.spine-rail {
  display: grid; grid-template-columns: repeat(7, 1fr); gap: 0;
  border: 1px solid var(--line); border-radius: 3px; overflow: hidden;
  background: var(--paper);
}
.spine-node {
  padding: 0.85rem 0.6rem; text-align: center; position: relative;
  border-right: 1px solid var(--line);
}
.spine-node:last-child { border-right: none; }
.spine-node .n {
  font-family:"JetBrains Mono",monospace; font-size:0.7rem; color:var(--brass-deep);
  display:block; margin-bottom:0.3rem;
}
.spine-node .w {
  font-family:"Spectral",serif; font-weight:600; font-size:0.98rem; color:var(--ink);
  line-height:1.15; display:block;
}
.spine-node .ch {
  display:block; margin-top:0.4rem; font-family:"Inter",sans-serif;
  font-size:0.68rem; color:var(--slate);
}
.spine-node:hover { background: rgba(180,136,74,0.07); }
@media (max-width: 760px) {
  .spine-rail { grid-template-columns: repeat(2, 1fr); }
  .spine-node { border-bottom: 1px solid var(--line); }
}

/* ---------- STAT BANNER ---------- */
.statbar {
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 1px;
  background: var(--line); border: 1px solid var(--line); border-radius: 3px;
  overflow: hidden; margin: 2.4rem 0;
}
.statbar .stat { background: var(--ink); padding: 1.3rem 1rem; text-align: center; }
.statbar .stat .num {
  font-family:"Spectral",serif; font-weight:700; font-size:1.9rem; color:#fff;
  line-height:1; display:block;
}
.statbar .stat .lab {
  font-family:"Inter",sans-serif; font-size:0.74rem; letter-spacing:0.06em;
  text-transform:uppercase; color:var(--brass); margin-top:0.5rem; display:block;
}
@media (max-width: 620px){ .statbar { grid-template-columns: repeat(2,1fr);} }

/* ---------- SECTION HEADERS ---------- */
.sec-eyebrow {
  font-family:"Inter",sans-serif; text-transform:uppercase; letter-spacing:0.14em;
  font-size:0.72rem; font-weight:600; color:var(--brass-deep);
  margin: 2.6rem 0 0.3rem;
}

/* ---------- THREE COMPANIONS ---------- */
.companions { display:grid; grid-template-columns:repeat(3,1fr); gap:1.1rem; margin:1.6rem 0; }
.companion {
  border:1px solid var(--line); border-radius:3px; padding:1.4rem 1.3rem; background:var(--paper);
  transition: border-color 0.15s ease, transform 0.15s ease;
}
.companion:hover { border-color: var(--brass); transform: translateY(-2px); }
.companion .glyph { font-size:1.5rem; color:var(--brass-deep); }
.companion h3 { font-size:1.1rem; margin:0.6rem 0 0.5rem; }
.companion p { font-size:0.92rem; color:#4a5058; margin-bottom:0.9rem; }
.companion a { font-family:"Inter",sans-serif; font-weight:600; font-size:0.88rem; }
@media (max-width: 760px){ .companions { grid-template-columns:1fr; } }

/* ---------- CHAPTER GRID ---------- */
.part-head {
  font-family:"Inter",sans-serif; font-weight:700; font-size:0.8rem;
  letter-spacing:0.1em; text-transform:uppercase; color:var(--slate);
  margin:1.8rem 0 0.8rem; padding-bottom:0.35rem; border-bottom:1px solid var(--line);
}
.chgrid { display:grid; grid-template-columns:repeat(2,1fr); gap:0.8rem; }
.chcard {
  display:block; border:1px solid var(--line); border-radius:3px;
  padding:1rem 1.1rem; background:var(--paper); text-decoration:none !important;
  border-bottom:1px solid var(--line) !important; transition:all 0.15s ease;
}
.chcard:hover { border-color:var(--brass) !important; background:#fff; }
.chcard .cn {
  font-family:"JetBrains Mono",monospace; font-size:0.72rem; color:var(--brass-deep);
}
.chcard .ct {
  font-family:"Spectral",serif; font-weight:600; font-size:1.02rem; color:var(--ink);
  display:block; margin-top:0.2rem; line-height:1.2;
}
.chcard .cm {
  font-family:"Inter",sans-serif; font-size:0.78rem; color:var(--slate); margin-top:0.4rem;
}
@media (max-width: 620px){ .chgrid { grid-template-columns:1fr; } }

/* ---------- LAB / DOWNLOAD CHIPS (chapter pages) ---------- */
.lab-callout {
  border:1px solid var(--line); border-left:3px solid var(--brass);
  border-radius:3px; background:rgba(180,136,74,0.05); padding:1.1rem 1.3rem; margin:1.2rem 0;
}
.lab-callout .modtitle { font-family:"Spectral",serif; font-weight:600; font-size:1.05rem; color:var(--ink); }
.lab-callout .week { font-family:"JetBrains Mono",monospace; font-size:0.74rem; color:var(--brass-deep); }
.downloads { display:flex; gap:0.6rem; flex-wrap:wrap; margin:1rem 0; }
.dl-chip {
  display:inline-flex; align-items:center; gap:0.4rem;
  border:1px solid var(--slate); border-radius:2px; padding:0.45rem 0.9rem;
  font-family:"Inter",sans-serif; font-weight:600; font-size:0.85rem;
  text-decoration:none !important; border-bottom:1px solid var(--slate) !important;
  color:var(--ink) !important; background:var(--paper);
}
.dl-chip:hover { border-color:var(--brass) !important; color:var(--brass-deep) !important; }
.dl-chip .ic { color:var(--brass-deep); }

/* ---------- AT A GLANCE ---------- */
.glance {
  border:1px solid var(--line); border-radius:3px; background:var(--paper);
  padding:1.2rem 1.4rem; margin:1.2rem 0 1.8rem;
}
.glance .glance-lab {
  font-family:"Inter",sans-serif; text-transform:uppercase; letter-spacing:0.12em;
  font-size:0.7rem; font-weight:600; color:var(--brass-deep); margin-bottom:0.5rem;
}

/* ---------- LOS list ---------- */
.los { margin:1rem 0; }
.los .los-item { margin-bottom:0.7rem; padding-left:0; }
.los .los-tag {
  font-family:"JetBrains Mono",monospace; font-weight:500; font-size:0.82rem;
  color:var(--brass-deep); margin-right:0.5rem;
}

/* ---------- exercise parts ---------- */
.expart {
  font-family:"Inter",sans-serif; font-weight:700; font-size:0.82rem;
  letter-spacing:0.06em; text-transform:uppercase; color:var(--slate);
  margin:1.6rem 0 0.6rem; padding-bottom:0.3rem; border-bottom:1px solid var(--line);
}
.solnote {
  font-size:0.86rem; color:var(--slate); font-style:italic;
  border-top:1px solid var(--line); padding-top:0.8rem; margin-top:1.4rem;
}

/* chapter-page prev/next tint */
.page-navigation a { color: var(--cite); }