/* ============================================================
   Docs & Learn: three-column reading layout
   ============================================================ */

.docs-shell{
  display:grid;
  grid-template-columns: 260px minmax(0,1fr) 220px;
  gap:0;
  max-width:1360px;
  margin:0 auto;
  align-items:start;
}

/* ---- left: nav tree ---- */
.docs-nav{
  position:sticky; top:var(--header-h);
  height:calc(100vh - var(--header-h));
  overflow-y:auto;
  padding:28px 18px 40px 28px;
  border-right:1px solid var(--border-soft);
}
.docs-nav-group{ margin-bottom:22px; }
.docs-nav-group-label{
  font-size:11px; text-transform:uppercase; letter-spacing:.07em; font-weight:700;
  color:var(--ink-faint); margin:0 0 6px; padding:0 10px;
}
.docs-nav a{
  display:block; font-size:13.5px; color:var(--ink-dim); padding:6px 10px;
  border-radius:var(--radius-sm); border-left:2px solid transparent; line-height:1.4;
}
.docs-nav a:hover{ color:var(--ink); background:rgba(255,255,255,.03); }
.docs-nav a.active{ color:var(--ink); border-left-color:var(--ember-flame); background:rgba(255,95,0,.07); font-weight:600; }

/* ---- middle: content ---- */
.docs-content{ padding:40px 48px 100px; min-width:0; }
.docs-breadcrumb{ font-size:12.5px; color:var(--ink-faint); font-family:var(--font-mono); margin-bottom:18px; }
.docs-breadcrumb a:hover{ color:var(--ink-dim); }
.docs-source-note{
  display:flex; align-items:center; gap:10px; flex-wrap:wrap;
  margin:28px 0 0; padding-top:20px; border-top:1px solid var(--border-soft);
  font-size:12.5px; color:var(--ink-faint);
}
.docs-source-note a{ display:inline-flex; align-items:center; gap:6px; color:var(--ink-dim); border:1px solid var(--border); border-radius:var(--radius-sm); padding:5px 12px; }
.docs-source-note a:hover{ color:var(--ink); border-color:var(--ink-faint); }
.docs-source-note svg{ width:12px; height:12px; }

.docs-pager{ display:flex; justify-content:space-between; gap:16px; margin-top:36px; }
.docs-pager a{
  flex:1; max-width:340px; border:1px solid var(--border); border-radius:var(--radius-md);
  padding:14px 16px; font-size:13px;
}
.docs-pager a:hover{ border-color:var(--ink-faint); }
.docs-pager .lbl{ color:var(--ink-faint); font-size:11px; text-transform:uppercase; letter-spacing:.05em; margin-bottom:4px; }
.docs-pager .nxt{ text-align:right; margin-left:auto; }
.docs-pager .ttl{ color:var(--ink); font-weight:600; }

/* ---- right: on-this-page toc ---- */
.docs-toc{
  position:sticky; top:var(--header-h);
  height:calc(100vh - var(--header-h));
  overflow-y:auto;
  padding:32px 24px 40px 0;
}
.docs-toc-label{ font-size:11px; text-transform:uppercase; letter-spacing:.07em; font-weight:700; color:var(--ink-faint); margin-bottom:10px; }
.docs-toc a{
  display:block; font-size:12.5px; color:var(--ink-faint); padding:4px 0 4px 12px;
  border-left:1px solid var(--border); line-height:1.4;
}
.docs-toc a.lvl3{ padding-left:22px; }
.docs-toc a:hover{ color:var(--ink); }
.docs-toc a.active{ color:var(--ember-amber); border-left-color:var(--ember-amber); }

@media (max-width: 1180px){
  .docs-shell{ grid-template-columns:240px minmax(0,1fr); }
  .docs-toc{ display:none; }
}
@media (max-width: 860px){
  .docs-shell{ display:block; }
  .docs-nav{ position:relative; top:0; height:auto; border-right:none; border-bottom:1px solid var(--border-soft); padding:20px; }
  .docs-content{ padding:32px 20px 80px; }
}

/* ---- doc index / landing grid ---- */
.doc-cat-grid{ display:grid; grid-template-columns:repeat(2,1fr); gap:14px; margin-top:8px; }
.doc-cat-card{ border:1px solid var(--border); border-radius:var(--radius-md); padding:18px 20px; }
.doc-cat-card h3{ font-size:14.5px; margin:0 0 10px; color:var(--ink); }
.doc-cat-card a{ display:block; font-size:13px; color:var(--ink-dim); padding:3px 0; }
.doc-cat-card a:hover{ color:var(--tag-blue); }
@media (max-width:700px){ .doc-cat-grid{ grid-template-columns:1fr; } }

/* ---- learn: lesson list ---- */
.learn-progress-bar{ height:6px; border-radius:4px; background:var(--surface-2); border:1px solid var(--border-soft); overflow:hidden; margin:14px 0 28px; }
.learn-progress-fill{ height:100%; background:var(--ember-flame); width:0%; transition:width .3s ease; }
.learn-level{ margin-bottom:30px; }
.learn-level h3{ font-family:var(--font-display); font-size:13px; text-transform:uppercase; letter-spacing:.06em; color:var(--ink-dim); margin:0 0 10px; display:flex; align-items:center; gap:10px; }
.learn-level h3 span{ color:var(--ink-faint); font-weight:400; }
.lesson-row{
  display:flex; align-items:center; gap:14px;
  padding:11px 14px; border-radius:var(--radius-sm); border:1px solid transparent;
}
.lesson-row:hover{ background:var(--surface); border-color:var(--border); }
.lesson-num{ font-family:var(--font-mono); font-size:12px; color:var(--ink-faint); width:26px; flex:none; }
.lesson-check{
  width:18px; height:18px; border-radius:5px; border:1.5px solid var(--border); flex:none;
  display:flex; align-items:center; justify-content:center; cursor:pointer;
}
.lesson-check.done{ background:var(--ember-flame); border-color:transparent; }
.lesson-check.done svg{ width:11px; height:11px; color:#0a0603; }
.lesson-title{ font-size:13.8px; color:var(--ink-dim); flex:1; }
.lesson-row:hover .lesson-title{ color:var(--ink); }

.lesson-nav-btns{ display:flex; gap:10px; margin-top:8px; }
.lesson-mark-btn{
  display:inline-flex; align-items:center; gap:8px; font-size:13px; color:var(--ink-dim);
  border:1px solid var(--border); border-radius:var(--radius-sm); padding:7px 14px; cursor:pointer; background:none; font-family:var(--font-body);
}
.lesson-mark-btn:hover{ border-color:var(--ink-faint); color:var(--ink); }
.lesson-mark-btn.done{ color:var(--ember-amber); border-color:rgba(255,135,0,.4); }