/* ADAM redesign — content screens (courses, lessons, quiz, library, books,
   history, careers, profile, demo). Scoped to #app; the tree view and the
   shell are styled in workspace.css. Uses only theme variables from tokens.css. */

#app{
  /* subject colour (set per route by app.js as --accent) mixed toward ink so it
     stays readable as text in light and dark modes */
  --acc-ink:color-mix(in srgb,var(--accent,var(--brand)) 70%,var(--ink));
  --acc-tint:color-mix(in srgb,var(--accent,var(--brand)) 11%,var(--surface));
  --btn:color-mix(in srgb,var(--brand) 86%,var(--ink));
  --btn-hover:color-mix(in srgb,var(--brand) 74%,var(--ink));
  --on-btn:var(--paper);
  --glass:color-mix(in srgb,var(--surface) 90%,transparent);
  --glass-alt:color-mix(in srgb,var(--surface-alt) 88%,transparent);
  --line-strong:color-mix(in srgb,var(--line) 60%,var(--muted));
  --lift:0 1px 0 color-mix(in srgb,var(--ink) 4%,transparent),0 14px 30px -18px color-mix(in srgb,var(--ink) 40%,transparent);
  --press:120ms var(--ease-out);
  color:var(--ink);
  font-family:var(--font-body);
}
#app :is(h1,h2,h3){font-family:var(--font-display);color:var(--ink);text-wrap:balance}
#app p{color:var(--muted)}
#app :focus-visible{outline:2px solid var(--brand);outline-offset:3px;border-radius:var(--r-sm)}

/* ---------- page heading ---------- */
#app .heading{display:flex;justify-content:space-between;align-items:flex-end;gap:var(--sp-5);margin:0 0 var(--sp-6);flex-wrap:wrap}
#app .heading>div:first-child{min-width:0;flex:1 1 420px}
#app .heading h1{font-size:clamp(1.9rem,1.2rem + 2.4vw,2.85rem);font-weight:700;letter-spacing:-.035em;line-height:1.05}
#app .heading p{margin-top:var(--sp-3);max-width:62ch;font-size:var(--fs-md);line-height:1.6}
/* source strings are typed in capitals; render them in sentence case */
#app .eyebrow{display:block;text-transform:lowercase;letter-spacing:0;font-size:var(--fs-sm);font-weight:600;color:var(--acc-ink);margin:0 0 var(--sp-2)}
#app .eyebrow::first-letter{text-transform:uppercase}
/* brand-only labels repeat the product name and add nothing: drop them */
#app .library-hero .eyebrow,
#app .heading:has(+ .reader-layout) .eyebrow,
#app .heading:has(+ .profile-grid) .eyebrow,
#app .heading:has(+ .filters #career-search) .eyebrow,
#app .heading:has(+ .filters #people-search) .eyebrow{display:none}

#app .section-head{display:flex;justify-content:space-between;align-items:baseline;gap:var(--sp-4);margin:var(--sp-7) 0 var(--sp-4);flex-wrap:wrap}
#app .section-head h2{font-size:var(--fs-lg);font-weight:650;letter-spacing:-.02em}
#app>h2{font-size:var(--fs-lg);margin:var(--sp-6) 0 var(--sp-3)}

/* ---------- small shared pieces ---------- */
#app .tag{display:inline-flex;align-items:center;font-size:var(--fs-xs);font-weight:550;line-height:1.3;color:var(--acc-ink);background:var(--acc-tint);padding:3px 9px;border-radius:var(--r-pill);white-space:nowrap}
#app .badge{display:inline-flex;align-items:center;gap:6px;font-size:var(--fs-xs);font-weight:500;color:var(--muted);background:var(--glass-alt);border:1px solid var(--line);border-radius:var(--r-pill);padding:5px 12px}
#app .pill-icon{display:grid;place-items:center;width:40px;height:40px;border-radius:var(--r-sm);background:var(--acc-tint);color:var(--acc-ink);font-size:20px;line-height:1}
#app .text-link{font-size:var(--fs-sm);font-weight:600;color:var(--acc-ink);text-decoration:underline;text-decoration-color:transparent;text-underline-offset:3px;transition:text-decoration-color var(--press)}
#app .text-link:hover{text-decoration-color:currentColor}
#app .muted{font-size:var(--fs-sm);color:var(--muted);line-height:1.55}
#app .i18n-note{font-size:var(--fs-xs);color:var(--muted)}
#app .back{display:inline-flex;align-items:center;gap:6px;font-size:var(--fs-sm);font-weight:500;color:var(--muted);margin:0 0 var(--sp-4) -8px;padding:6px 12px 6px 8px;border-radius:var(--r-pill);transition:background-color var(--press),color var(--press)}
#app .back:hover{background:var(--glass-alt);color:var(--ink)}
#app .breadcrumbs{display:flex;flex-wrap:wrap;gap:6px 10px;font-size:var(--fs-sm);color:var(--muted);margin-bottom:var(--sp-4)}
#app .breadcrumbs a:hover{color:var(--ink);text-decoration:underline;text-underline-offset:3px}
#app .notice{margin:var(--sp-6) 0;padding:var(--sp-3) var(--sp-4) var(--sp-3) var(--sp-5);font-size:var(--fs-sm);line-height:1.55;color:var(--muted);background:var(--glass-alt);border:1px solid var(--line);border-left:3px solid color-mix(in srgb,var(--apricot) 75%,var(--line));border-radius:var(--r-sm);max-width:90ch}
#app .empty{display:grid;justify-items:center;gap:var(--sp-3);padding:var(--sp-7) var(--sp-5);text-align:center;background:var(--glass);border:1.5px dashed var(--line-strong);border-radius:var(--r-lg);color:var(--muted);grid-column:1/-1}
#app .empty h2{font-size:var(--fs-xl);letter-spacing:-.02em}
#app .empty p{max-width:46ch}
#app .empty .action-row{margin-top:var(--sp-2)}

/* ---------- buttons ---------- */
#app :is(.primary,.secondary){display:inline-flex;align-items:center;justify-content:center;gap:8px;min-height:44px;padding:0 18px;border-radius:var(--r-sm);font:600 var(--fs-sm)/1.2 var(--font-body);letter-spacing:0;text-align:center;cursor:pointer;
  transition:background-color var(--press),border-color var(--press),transform var(--press),box-shadow var(--press);filter:none}
#app .primary{background:var(--btn);color:var(--on-btn);border:1px solid transparent;box-shadow:0 1px 0 color-mix(in srgb,var(--ink) 12%,transparent),inset 0 1px 0 rgb(255 255 255/.14)}
#app .primary:hover{background:var(--btn-hover);transform:translateY(-1px);box-shadow:0 6px 16px -8px color-mix(in srgb,var(--brand) 70%,transparent)}
#app .secondary{background:var(--surface);color:var(--ink);border:1px solid var(--line-strong)}
#app .secondary:hover{background:var(--surface-alt);border-color:color-mix(in srgb,var(--ink) 35%,var(--line))}
#app :is(.primary,.secondary):active{transform:translateY(1px) scale(.98);box-shadow:none}
#app :is(.primary,.secondary):disabled{opacity:.5;cursor:not-allowed;transform:none;box-shadow:none}
#app .action-row{display:flex;flex-wrap:wrap;align-items:center;gap:var(--sp-3);margin-top:var(--sp-5)}

/* ---------- form controls ---------- */
#app :is(input:not([type=radio]):not([type=checkbox]),select,textarea){font:400 var(--fs-md)/1.4 var(--font-body);color:var(--ink);background-color:var(--surface);border:1px solid var(--line-strong);border-radius:var(--r-sm);min-height:44px;padding:10px 14px;transition:border-color var(--press),box-shadow var(--press)}
#app :is(input,select,textarea)::placeholder{color:color-mix(in srgb,var(--muted) 85%,transparent)}
#app :is(input,select,textarea):hover{border-color:color-mix(in srgb,var(--ink) 30%,var(--line))}
#app :is(input,select,textarea):focus{outline:none;border-color:var(--brand);box-shadow:0 0 0 3px color-mix(in srgb,var(--brand) 22%,transparent)}
#app :is(input,select,textarea):focus-visible{outline:none}
#app select{appearance:none;-webkit-appearance:none;padding-right:38px;cursor:pointer;
  background-image:linear-gradient(45deg,transparent 50%,var(--muted) 50%),linear-gradient(135deg,var(--muted) 50%,transparent 50%);
  background-position:calc(100% - 19px) 50%,calc(100% - 14px) 50%;background-size:5px 5px;background-repeat:no-repeat}
#app textarea:not([type]){width:100%;min-height:150px;resize:vertical;line-height:1.6;margin:var(--sp-2) 0 var(--sp-3)}
#app input[type=radio]{accent-color:var(--brand);width:18px;height:18px;margin:0;flex-shrink:0}

#app .filters{display:flex;flex-wrap:wrap;gap:var(--sp-2);align-items:center;margin:0 0 var(--sp-5);padding:var(--sp-2);background:var(--glass-alt);border:1px solid var(--line);border-radius:var(--r-md)}
#app .filters input{flex:1 1 240px;min-width:0}
#app .filters input[type=search]{padding-left:40px;
  background-image:radial-gradient(circle,transparent 4.5px,var(--muted) 5px,var(--muted) 6.3px,transparent 6.8px),linear-gradient(45deg,transparent 38%,var(--muted) 38% 62%,transparent 62%);
  background-size:16px 16px,7px 7px;background-position:12px calc(50% - 1px),23px calc(50% + 6px);background-repeat:no-repeat}
#app .filters select{flex:0 1 auto;max-width:100%;font-size:var(--fs-sm)}
#app .book-count{font-size:var(--fs-sm);color:var(--muted);margin:-8px 0 var(--sp-4)}

/* ---------- cards ---------- */
#app .cards{display:grid;grid-template-columns:repeat(auto-fill,minmax(min(100%,264px),1fr));gap:var(--sp-4);align-items:stretch}
#app .card{position:relative;display:flex;flex-direction:column;min-width:0;padding:var(--sp-5);background:var(--glass);border:1px solid var(--line);border-radius:var(--r-md);color:var(--ink);box-shadow:none;
  transition:border-color .2s var(--ease-out),transform .2s var(--ease-out),box-shadow .2s var(--ease-out)}
#app a.card:hover{border-color:color-mix(in srgb,var(--accent,var(--brand)) 55%,var(--line));transform:translateY(-2px);box-shadow:var(--lift)}
#app a.card:active{transform:translateY(0)}
#app .card-top{display:flex;align-items:center;justify-content:space-between;gap:var(--sp-2);margin-bottom:var(--sp-4)}
#app .card h3{font-size:var(--fs-lg);font-weight:650;line-height:1.25;letter-spacing:-.015em}
#app .card p{font-size:var(--fs-sm);line-height:1.5;margin:var(--sp-2) 0 var(--sp-4)}
#app .card .bottom{margin-top:auto;padding-top:var(--sp-3);border-top:1px solid var(--line);display:flex;justify-content:space-between;align-items:center;gap:var(--sp-3);font-size:var(--fs-xs);color:var(--muted)}
#app .card .bottom span:last-child{color:var(--acc-ink);font-weight:600;white-space:nowrap}
#app .progress{height:6px;margin:auto 0 var(--sp-2);background:color-mix(in srgb,var(--accent,var(--brand)) 13%,var(--line));border-radius:var(--r-pill);overflow:hidden}
#app .progress+.bottom{margin-top:0}
#app .progress div{height:100%;min-width:6px;border-radius:inherit;background:var(--accent,var(--brand));transition:width .5s var(--ease-out)}

/* ---------- course page: lessons grow along one stem ---------- */
#app .course-layout{display:grid;grid-template-columns:minmax(0,1fr) 300px;gap:var(--sp-6);align-items:start}
#app .lesson-list{position:relative;display:grid;gap:var(--sp-2)}
#app .lesson-list::before{content:'';position:absolute;left:calc(var(--sp-4) + 19px);top:28px;bottom:28px;width:2px;border-radius:2px;background:linear-gradient(var(--accent,var(--brand)),color-mix(in srgb,var(--accent,var(--brand)) 20%,var(--line)))}
#app .lesson-row{position:relative;display:flex;align-items:center;gap:var(--sp-4);padding:var(--sp-3) var(--sp-4);min-height:72px;background:var(--glass);border:1px solid var(--line);border-radius:var(--r-md);color:var(--ink);transition:border-color .18s,background-color .18s}
#app .lesson-row:hover{border-color:color-mix(in srgb,var(--accent,var(--brand)) 55%,var(--line));background:var(--surface)}
#app .lesson-row>div{min-width:0;flex:1}
#app .lesson-row h3{font-size:var(--fs-md);font-weight:600;line-height:1.3;letter-spacing:-.01em}
#app .lesson-row p{font-size:var(--fs-xs);margin-top:3px}
#app .lesson-num{position:relative;z-index:1;flex-shrink:0;display:grid;place-items:center;width:40px;height:40px;border-radius:50%;background:var(--surface);border:2px solid var(--accent,var(--brand));color:var(--acc-ink);font:700 var(--fs-sm)/1 var(--font-display);font-variant-numeric:tabular-nums;transition:background-color .18s,color .18s}
#app .lesson-row:hover .lesson-num{background:var(--accent,var(--brand));color:var(--surface)}
#app .lesson-row .bookmark,#app .lesson-row .arrow{margin-left:auto;font-size:var(--fs-xs);font-weight:600;color:var(--acc-ink);white-space:nowrap}
#app .course-layout>.branch-panel{position:sticky;top:var(--sp-5);padding:var(--sp-5);background:var(--glass-alt);border:1px solid var(--line);border-radius:var(--r-lg)}
#app .course-layout>.branch-panel h2{font-size:var(--fs-lg)}
#app .course-layout>.branch-panel>p{font-size:var(--fs-sm);margin:var(--sp-2) 0 var(--sp-3)}
#app .course-layout>.branch-panel .notice{margin:var(--sp-4) 0 0;font-size:var(--fs-xs)}

/* book reference rows: a small spine echoes the covers */
#app .book-mini{display:grid;grid-template-columns:8px 1fr;column-gap:var(--sp-3);align-items:center;padding:var(--sp-3) 0;border-bottom:1px solid var(--line);font-size:var(--fs-sm);font-weight:550;line-height:1.35;color:var(--ink)}
#app .book-mini::before{content:'';grid-row:1/3;align-self:stretch;min-height:30px;border-radius:2px 3px 3px 2px;background:var(--accent,var(--brand));box-shadow:inset 2px 0 0 rgb(0 0 0/.22)}
#app .book-mini small{grid-column:2;display:block;font-size:var(--fs-xs);font-weight:400;color:var(--muted);margin-top:2px}
#app a.book-mini:hover{color:var(--acc-ink)}
#app .book-mini:last-child{border-bottom:0}

/* ---------- lesson & attempt ---------- */
#app .lesson-body{max-width:800px;margin:0 auto}
#app .paper{position:relative;background:var(--glass);border:1px solid var(--line);border-radius:var(--r-lg);padding:clamp(20px,4vw,40px);margin-bottom:var(--sp-5)}
#app .paper h2{font-size:var(--fs-xl);font-weight:650;letter-spacing:-.025em;line-height:1.2;max-width:34ch}
#app .step-label{display:flex;align-items:center;gap:var(--sp-2);text-transform:none;letter-spacing:0;font-size:var(--fs-sm);font-weight:600;color:var(--acc-ink);margin:0 0 var(--sp-3)}
#app .step-label::before{content:'';flex-shrink:0;width:10px;height:10px;border-radius:50% 0;background:var(--accent,var(--brand));transform:rotate(45deg) scale(.9)}
#app .reading{font-family:var(--font-body);font-size:1.1875rem;line-height:1.75;color:var(--ink);max-width:68ch;white-space:pre-wrap;margin:var(--sp-4) 0 var(--sp-5)}
#app .lesson-body>section.paper:last-of-type .step-label{text-transform:lowercase}
#app .lesson-body>section.paper:last-of-type .step-label::first-letter{text-transform:uppercase}
#app .meta-row{font-size:var(--fs-xs);color:var(--muted);margin:0 0 var(--sp-4)}
#app .quiz-options{display:grid;gap:var(--sp-2);margin:var(--sp-5) 0}
#app .quiz-option{display:flex;align-items:center;gap:var(--sp-3);min-height:52px;padding:12px 16px;background:var(--surface);border:1px solid var(--line-strong);border-radius:var(--r-sm);font-size:var(--fs-md);line-height:1.4;color:var(--ink);cursor:pointer;transition:border-color var(--press),background-color var(--press),box-shadow var(--press)}
#app .quiz-option:hover{border-color:color-mix(in srgb,var(--brand) 60%,var(--line))}
#app .quiz-option:has(input:checked){border-color:var(--brand);background:color-mix(in srgb,var(--brand) 9%,var(--surface));box-shadow:inset 0 0 0 1px var(--brand)}
#app .quiz-option:has(input:focus-visible){outline:2px solid var(--brand);outline-offset:2px}
#app .quiz-option:has(input:disabled){cursor:default;opacity:.75}
#app .quiz-result{margin:var(--sp-4) 0;padding:var(--sp-4) var(--sp-5);background:var(--surface-alt);border:1px solid var(--line);border-left:4px solid var(--accent,var(--brand));border-radius:var(--r-md);animation:adam-reveal .35s var(--ease-out)}
#app .quiz-result strong{display:block;font:650 var(--fs-lg)/1.3 var(--font-display);color:var(--ink);letter-spacing:-.01em}
#app .quiz-result p{font-size:var(--fs-md);line-height:1.6;color:var(--ink);margin-top:var(--sp-2);max-width:68ch}
#app .quiz-result .action-row{margin-top:var(--sp-3)}
@keyframes adam-reveal{from{opacity:0;transform:translateY(6px)}}
#app .rubric{list-style:none;padding:0;margin:var(--sp-4) 0 var(--sp-5);display:grid;gap:var(--sp-2);max-width:68ch}
#app .rubric li{position:relative;padding-left:28px;font-size:var(--fs-md);line-height:1.5;color:var(--ink)}
#app .rubric li::before{content:'';position:absolute;left:2px;top:.3em;width:14px;height:14px;border-radius:4px;border:1.5px solid var(--accent,var(--brand));background:var(--acc-tint)}
#app label[for=practice]{display:block;font-size:var(--fs-sm);font-weight:600;color:var(--ink);margin-top:var(--sp-2)}
#app .lesson-body>.action-row{justify-content:space-between;margin:var(--sp-6) 0 var(--sp-4);padding-top:var(--sp-5);border-top:1px solid var(--line)}
/* score: big display numerals */
#app .result-num{font:800 var(--fs-xl)/1 var(--font-display);font-variant-numeric:tabular-nums;letter-spacing:-.03em;color:var(--acc-ink)}
#app .paper>.result-num{display:inline-flex;align-items:baseline;font-size:clamp(3rem,2rem + 4vw,4.75rem);padding:var(--sp-3) var(--sp-5);border-radius:var(--r-md);background:var(--acc-tint);line-height:1}

/* ---------- history ---------- */
#app .history-item{display:flex;align-items:center;gap:var(--sp-4);padding:var(--sp-3) var(--sp-4);margin-bottom:var(--sp-2);background:var(--glass);border:1px solid var(--line);border-radius:var(--r-md)}
#app .history-item .result-num{flex-shrink:0;display:grid;place-items:center;width:64px;height:56px;border-radius:var(--r-sm);background:var(--acc-tint);font-size:var(--fs-lg)}
#app .history-item>div:not(.result-num){min-width:0;flex:1}
#app .history-item h3{font-size:var(--fs-md);font-weight:600;line-height:1.3}
#app .history-item p{font-size:var(--fs-xs);margin-top:2px}
#app .history-item .secondary{margin-left:auto;flex-shrink:0;min-height:40px}

/* ---------- library ---------- */
#app .library-hero{display:flex;align-items:flex-end;justify-content:space-between;gap:var(--sp-6);padding:0 0 var(--sp-5);margin:0 0 var(--sp-6);background:none;border-radius:0;border-bottom:1px solid var(--line)}
#app .library-hero h1{font-size:clamp(2.2rem,1.4rem + 3vw,3.4rem);font-weight:750;letter-spacing:-.04em;line-height:1}
#app .library-hero p{margin-top:var(--sp-3);max-width:60ch;font-size:var(--fs-md);color:var(--muted);opacity:1}
/* the glyph becomes a little shelf of spines */
#app .library-mark{position:relative;flex-shrink:0;width:176px;height:84px;font-size:0;color:transparent;border-bottom:5px solid color-mix(in srgb,var(--ink) 55%,var(--line));border-radius:0 0 2px 2px;
  background:
   linear-gradient(var(--brand),var(--brand)) 4px 100%/18px 86% no-repeat,
   linear-gradient(var(--apricot),var(--apricot)) 25px 100%/14px 66% no-repeat,
   linear-gradient(var(--glacier),var(--glacier)) 42px 100%/22px 92% no-repeat,
   linear-gradient(color-mix(in srgb,var(--brand) 55%,var(--ink)),color-mix(in srgb,var(--brand) 55%,var(--ink))) 67px 100%/12px 74% no-repeat,
   linear-gradient(color-mix(in srgb,var(--apricot) 60%,var(--surface)),color-mix(in srgb,var(--apricot) 60%,var(--surface))) 82px 100%/20px 80% no-repeat,
   linear-gradient(var(--line-strong),var(--line-strong)) 105px 100%/16px 60% no-repeat}
#app .library-mark::after{content:'';position:absolute;left:124px;bottom:0;width:15px;height:62px;background:var(--brand);transform-origin:bottom left;transform:rotate(18deg);border-radius:1px}
#app .category-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(min(100%,200px),1fr));gap:var(--sp-3)}
#app .category-card{position:relative;display:flex;flex-direction:column;min-height:132px;padding:var(--sp-4) var(--sp-5);background:var(--glass);border:1px solid var(--line);border-radius:var(--r-md);overflow:hidden;color:var(--ink);transition:border-color .2s var(--ease-out),transform .2s var(--ease-out),box-shadow .2s var(--ease-out)}
#app .category-card::after{content:'';position:absolute;left:var(--sp-5);right:auto;top:auto;bottom:0;width:40px;height:3px;opacity:1;border-radius:3px 3px 0 0;background:var(--cat)}
#app .category-card:hover{transform:translateY(-2px);border-color:color-mix(in srgb,var(--cat) 50%,var(--line));box-shadow:var(--lift)}
#app .category-card .cat-icon{display:grid;place-items:center;width:44px;height:44px;border-radius:var(--r-sm);font-size:22px;color:color-mix(in srgb,var(--cat) 75%,var(--ink));background:color-mix(in srgb,var(--cat) 13%,var(--surface));margin-bottom:auto}
#app .category-card strong{font:650 var(--fs-md)/1.25 var(--font-display);margin-top:var(--sp-4)}
#app .category-card small{font-size:var(--fs-xs);color:var(--muted);margin-top:2px}
#app .authors{display:flex;flex-wrap:wrap;gap:var(--sp-2);margin:0}
#app .author-chip{display:inline-flex;align-items:center;gap:var(--sp-2);min-height:44px;padding:4px 16px 4px 4px;background:var(--glass);border:1px solid var(--line);border-radius:var(--r-pill);font-size:var(--fs-sm);font-weight:500;color:var(--ink);transition:border-color var(--press),background-color var(--press),transform var(--press)}
#app .author-chip:hover{border-color:var(--brand);background:var(--surface)}
#app .author-chip:active{transform:scale(.97)}
#app .author-chip span{display:grid;place-items:center;width:34px;height:34px;border-radius:50%;background:color-mix(in srgb,var(--brand) 14%,var(--surface));color:color-mix(in srgb,var(--brand) 75%,var(--ink));font:700 var(--fs-xs)/1 var(--font-display)}
#app .library-results{scroll-margin-top:24px}

/* book card + a cloth-bound cover with a school-notebook label */
#app .book-card{isolation:isolate;padding:var(--sp-5) var(--sp-5) var(--sp-5)}
/* a small display shelf behind each cover */
#app .book-card::before{content:'';position:absolute;z-index:-1;left:0;right:0;top:0;height:244px;border-radius:calc(var(--r-md) - 1px) calc(var(--r-md) - 1px) 0 0;
  background:linear-gradient(transparent calc(100% - 6px),color-mix(in srgb,var(--line) 70%,var(--muted)) calc(100% - 6px) calc(100% - 4px),transparent calc(100% - 4px)),radial-gradient(60% 40% at 50% 100%,color-mix(in srgb,var(--accent,var(--brand)) 14%,transparent),transparent 70%),var(--glass-alt)}
#app .book-cover{position:relative;isolation:isolate;width:152px;height:206px;margin:0 auto var(--sp-6);padding:16px 12px 14px 26px;display:flex;flex-direction:column;justify-content:space-between;gap:var(--sp-2);color:#fff;overflow:hidden;
  border:0;border-radius:4px var(--r-sm) var(--r-sm) 4px;
  background:
   repeating-linear-gradient(0deg,rgb(255 255 255/.035) 0 1px,transparent 1px 3px),
   repeating-linear-gradient(90deg,rgb(0 0 0/.04) 0 1px,transparent 1px 3px),
   linear-gradient(160deg,color-mix(in srgb,var(--accent,var(--brand)) 88%,#fff) 0%,var(--accent,var(--brand)) 45%,color-mix(in srgb,var(--accent,var(--brand)) 68%,#0b1712) 100%);
  box-shadow:inset 14px 0 0 -1px color-mix(in srgb,var(--accent,var(--brand)) 62%,#0b1712),inset 15px 0 0 -1px rgb(255 255 255/.18),inset -1px 0 0 rgb(255 255 255/.2),0 1px 2px rgb(0 0 0/.12),0 10px 18px -12px rgb(0 0 0/.45);
  transition:transform .25s var(--ease-out),box-shadow .25s var(--ease-out)}
/* headband stitches on the spine */
#app .book-cover::before{content:'';position:absolute;left:3px;top:14px;bottom:14px;width:8px;z-index:-1;
  background:linear-gradient(rgb(255 255 255/.32),rgb(255 255 255/.32)) 0 0/100% 2px no-repeat,linear-gradient(rgb(255 255 255/.32),rgb(255 255 255/.32)) 0 6px/100% 2px no-repeat,
   linear-gradient(rgb(255 255 255/.32),rgb(255 255 255/.32)) 0 100%/100% 2px no-repeat,linear-gradient(rgb(255 255 255/.32),rgb(255 255 255/.32)) 0 calc(100% - 6px)/100% 2px no-repeat}
#app .book-cover::after{content:'';position:absolute;right:-30px;top:-30px;width:90px;height:90px;border-radius:50%;background:radial-gradient(rgb(255 255 255/.16),transparent 70%);z-index:-1}
#app .book-cover small{font:600 10px/1.3 var(--font-body);letter-spacing:.06em;text-transform:none;color:rgb(255 255 255/.88)}
#app .book-cover small:last-child{letter-spacing:.1em;font-size:9.5px;color:rgb(255 255 255/.75)}
#app .book-cover strong{align-self:stretch;display:-webkit-box;-webkit-line-clamp:4;-webkit-box-orient:vertical;overflow:hidden;
  font:700 var(--fs-sm)/1.22 var(--font-display);letter-spacing:-.01em;color:#1d2621;
  padding:8px 9px 12px;overflow-wrap:anywhere;hyphens:auto;border-radius:3px;
  background:linear-gradient(transparent calc(100% - 7px),rgb(29 38 33/.18) calc(100% - 7px) calc(100% - 6px),transparent calc(100% - 6px)),#f7f3e8;
  box-shadow:0 0 0 3px rgb(247 243 232/.28),0 2px 4px rgb(0 0 0/.18)}
#app .book-card:hover .book-cover{transform:translateY(-3px) rotate(-.8deg);box-shadow:inset 14px 0 0 -1px color-mix(in srgb,var(--accent,var(--brand)) 62%,#0b1712),inset 15px 0 0 -1px rgb(255 255 255/.18),0 2px 3px rgb(0 0 0/.12),0 18px 26px -14px rgb(0 0 0/.5)}
#app .book-card h3{font-size:var(--fs-md);font-weight:650;line-height:1.3}
#app .book-card .book-author{font-size:var(--fs-sm)!important;font-weight:500;color:var(--ink)!important;margin:var(--sp-1) 0 var(--sp-2)}
#app .book-card>p:not(.book-author){font-size:var(--fs-sm);margin:var(--sp-1) 0 var(--sp-2)}
#app .book-kind{display:inline-flex;align-self:flex-start;font-size:var(--fs-xs);color:var(--acc-ink);background:var(--acc-tint);padding:2px 9px;border-radius:var(--r-pill);margin-bottom:var(--sp-2)}
#app .book-card .license{font-size:var(--fs-xs);line-height:1.45;color:var(--muted);margin:0 0 var(--sp-4)}
#app .book-actions{display:flex;flex-wrap:wrap;gap:var(--sp-2);margin-top:auto}
#app .book-actions a{min-height:40px;padding:0 14px;font-size:var(--fs-xs)}
#app .book-actions a:first-child{flex:1 1 auto}

/* book page / reader */
#app .reader-layout{display:grid;grid-template-columns:260px minmax(0,1fr);gap:var(--sp-6);align-items:start}
#app .reader-layout aside{min-width:0}
#app .reader-layout aside .paper{padding:var(--sp-5)!important;border-radius:var(--r-md)}
#app .reader-layout aside h3{font-size:var(--fs-md);margin:var(--sp-5) 0 var(--sp-1)}
#app .reader-layout aside .action-row{flex-direction:column;align-items:stretch}
#app .reader-layout section>.notice{margin-top:0}
#app .reader-tools{display:flex;flex-wrap:wrap;align-items:center;gap:var(--sp-2);margin:var(--sp-4) 0}
#app .reader-tools input{width:84px;min-height:40px;padding:6px 10px;margin-left:6px}
#app .reader-tools .secondary{min-width:44px;padding:0 12px}
#app .reader-page{max-width:72ch;padding:clamp(20px,4vw,44px);font:400 1.0625rem/1.75 var(--font-body);color:var(--ink);background:var(--glass);border:1px solid var(--line);border-radius:var(--r-lg);white-space:pre-wrap;overflow-wrap:anywhere}
#app .pdf-frame{width:100%;height:78vh;border:1px solid var(--line);border-radius:var(--r-md);background:var(--surface)}

/* ---------- careers ---------- */
#app .career-card{border-top:1px solid var(--line);--accent:var(--brand)}
#app .career-card::before{content:'';position:absolute;left:var(--sp-5);top:-1px;width:40px;height:3px;border-radius:0 0 3px 3px;background:var(--brand)}
#app .career-card p{display:-webkit-box;-webkit-line-clamp:4;-webkit-box-orient:vertical;overflow:hidden}
#app .subject-chips{display:flex;flex-wrap:wrap;gap:6px;margin:0 0 var(--sp-4)}
#app .subject-chips a{display:inline-flex;align-items:center;min-height:32px;font-size:var(--fs-xs);font-weight:500;color:var(--ink);background:var(--glass-alt);border:1px solid var(--line);border-radius:var(--r-pill);padding:4px 12px;transition:border-color var(--press)}
#app .subject-chips a:hover{border-color:var(--brand)}
#app .card .subject-chips{margin-top:auto}
/* career route: numbered steps along a stem */
#app .journey-step{position:relative;display:flex;align-items:center;gap:var(--sp-4);margin:0 0 var(--sp-2);padding:var(--sp-3) var(--sp-4);min-height:72px;background:var(--glass);border:1px solid var(--line);border-radius:var(--r-md);color:var(--ink);max-width:760px;transition:border-color .18s}
#app .journey-step+.journey-step::before{content:'';position:absolute;left:calc(var(--sp-4) + 19px);top:calc(-1 * var(--sp-2) - 1px);height:calc(var(--sp-2) + 1px);width:2px;background:var(--brand)}
#app .journey-step:hover{border-color:var(--brand)}
#app .journey-step>span:first-child{flex-shrink:0;display:grid;place-items:center;width:40px;height:40px;border-radius:50%;background:var(--surface);border:2px solid var(--brand);color:color-mix(in srgb,var(--brand) 75%,var(--ink));font:700 var(--fs-sm)/1 var(--font-display)}
#app .journey-step>div{flex:1;min-width:0}
#app .journey-step h3{font-size:var(--fs-md);font-weight:600}
#app .journey-step p{font-size:var(--fs-xs);margin-top:2px}
#app .journey-step .arrow{color:color-mix(in srgb,var(--brand) 75%,var(--ink))}

/* ---------- profile & appearance ---------- */
#app .profile-grid{display:grid;grid-template-columns:minmax(0,1fr) 320px;gap:var(--sp-5);align-items:start}
#app .profile-grid>aside.paper{position:sticky;top:var(--sp-5);background:var(--glass-alt)}
#app .profile-grid>aside h2{font-size:var(--fs-xl)}
#app .profile-grid>aside h3{font-size:var(--fs-md);margin-bottom:var(--sp-2)}
#app .profile-grid>aside .subject-chips{margin:var(--sp-2) 0 var(--sp-4);color:var(--muted);font-size:var(--fs-sm)}
#app .profile-grid .profile-avatar{border-radius:var(--r-md)!important;font-family:var(--font-display);font-weight:700}
#app .profile-fields{display:grid;grid-template-columns:1fr 1fr;gap:var(--sp-4)}
#app .profile-fields label{display:block;font-size:var(--fs-sm);font-weight:600;color:var(--ink)}
#app .profile-fields :is(input,textarea){display:block;width:100%;margin:6px 0 0;font-weight:400}
#app .profile-fields .wide{grid-column:1/-1}
#app #profile-message:empty{display:none}
#app #appearance>p.muted{margin-top:var(--sp-2)}
#app .theme-picker{display:grid;grid-template-columns:repeat(5,minmax(0,1fr));gap:var(--sp-3);margin:var(--sp-4) 0}
#app .theme-tile{position:relative;display:flex;flex-direction:column;gap:var(--sp-2);padding:6px 6px 10px;background:var(--surface);border:1px solid var(--line-strong);border-radius:var(--r-md);font-size:var(--fs-sm);font-weight:550;color:var(--ink);cursor:pointer;text-align:center;transition:border-color var(--press),transform var(--press),box-shadow var(--press)}
#app .theme-tile:hover{border-color:color-mix(in srgb,var(--ink) 35%,var(--line));transform:translateY(-1px)}
#app .theme-tile:active{transform:scale(.97)}
#app .theme-tile.selected{border-color:var(--brand);box-shadow:inset 0 0 0 1px var(--brand)}
#app .theme-tile.selected::after{content:'✓';position:absolute;top:12px;right:12px;display:grid;place-items:center;width:22px;height:22px;border-radius:50%;background:var(--btn);color:var(--on-btn);font-size:12px;font-weight:700}
#app .theme-swatch{display:block;height:64px;margin:0;border-radius:calc(var(--r-md) - 5px);background:var(--swatch);box-shadow:inset 0 0 0 1px rgb(0 0 0/.06)}
#app .global-controls{gap:var(--sp-2)}
#app .global-controls select{min-height:44px;max-width:none;font-size:var(--fs-sm);padding:8px 36px 8px 12px}
#app .icon-button{min-width:44px;height:44px;border-radius:var(--r-sm);border:1px solid var(--line-strong);background:var(--surface);color:var(--ink);font-size:18px;transition:background-color var(--press),transform var(--press)}
#app .icon-button:hover{background:var(--surface-alt)}
#app .icon-button:active{transform:scale(.95)}
#app .theme-preview-note{font-size:var(--fs-sm);color:var(--muted)}

/* ---------- demo screens ---------- */
#app .count-strip{display:flex;flex-wrap:wrap;gap:var(--sp-2);margin:0 0 var(--sp-3);font-size:var(--fs-xs);color:var(--muted)}
#app .count-strip span{padding:3px 10px;border-radius:var(--r-pill);background:var(--glass-alt);border:1px solid var(--line)}
#app .card details{border-top:1px solid var(--line);padding-top:var(--sp-2)}
#app .card details>summary{cursor:pointer;font-size:var(--fs-sm);font-weight:600;color:var(--acc-ink);padding:6px 0;list-style-position:inside}
#app .card details .book-mini{font-size:var(--fs-xs);font-weight:500;padding:var(--sp-2) 0}
#app .card>.muted:last-child{margin-top:var(--sp-3)!important;font-size:var(--fs-xs)}
#app .card .profile-avatar{border-radius:var(--r-sm);font-family:var(--font-display)}

/* ---------- responsive ---------- */
@media (max-width:1100px){
  #app .course-layout{grid-template-columns:minmax(0,1fr) 260px;gap:var(--sp-5)}
  #app .profile-grid{grid-template-columns:1fr}
  #app .profile-grid>aside.paper{position:static}
}
@media (max-width:900px){
  #app .course-layout,#app .reader-layout{grid-template-columns:1fr}
  #app .course-layout>.branch-panel{position:static}
  #app .reader-layout aside{display:block}
  #app .reader-layout aside .action-row{flex-direction:row}
  #app .theme-picker{grid-template-columns:repeat(3,minmax(0,1fr))}
}
@media (max-width:640px){
  #app .heading{margin-bottom:var(--sp-5)}
  #app .heading p{font-size:var(--fs-sm)}
  #app .heading .badge{display:none}
  #app .section-head{margin:var(--sp-6) 0 var(--sp-3)}
  #app .library-mark{display:none}
  #app .library-hero{padding-bottom:var(--sp-4);margin-bottom:var(--sp-5)}
  #app .filters{padding:6px}
  #app .filters input{flex-basis:100%}
  #app .filters select{flex:1 1 calc(50% - 4px);min-width:0}
  #app .cards{grid-template-columns:1fr;gap:var(--sp-3)}
  #app .card{padding:var(--sp-4)}
  #app .card h3{font-size:var(--fs-md)}
  #app .category-grid{grid-template-columns:1fr 1fr;gap:var(--sp-2)}
  #app .category-card{min-height:128px;padding:var(--sp-4)}
  #app .category-card::after{left:var(--sp-4)}
  #app .paper{border-radius:var(--r-md)}
  #app .paper h2{font-size:var(--fs-lg)}
  #app .reading{font-size:1.0625rem;line-height:1.7}
  #app .lesson-row,#app .journey-step{gap:var(--sp-3);padding:var(--sp-3);min-height:64px}
  #app .lesson-num,#app .journey-step>span:first-child{width:34px;height:34px;font-size:var(--fs-xs)}
  #app .lesson-list::before,#app .journey-step+.journey-step::before{left:calc(var(--sp-3) + 16px)}
  #app .lesson-row .bookmark{display:none}
  #app .lesson-body>.action-row{flex-direction:column-reverse;align-items:stretch}
  #app .history-item{flex-wrap:wrap;gap:var(--sp-3)}
  #app .history-item .result-num{width:52px;height:48px;font-size:var(--fs-md)}
  #app .history-item>div:not(.result-num){flex:1 1 calc(100% - 70px)}
  #app .history-item .secondary{margin-left:0!important;width:100%}
  /* book card turns horizontal so the shelf stays scannable */
  #app .book-card{display:grid;grid-template-columns:104px minmax(0,1fr);column-gap:var(--sp-4);align-content:start;padding:var(--sp-3)}
  #app .book-card>*{grid-column:2}
  #app .book-card::before{display:none}
  #app .book-card .book-cover{grid-column:1;grid-row:1/span 5;width:104px;height:150px;margin:0;padding:10px 8px 10px 20px;align-self:start}
  #app .book-cover small{font-size:8px!important;letter-spacing:.04em!important}
  #app .book-cover strong{font-size:11px;padding:6px 6px 9px;-webkit-line-clamp:5}
  #app .book-card .license{margin-bottom:0}
  #app .book-card .book-actions{grid-column:1/-1;margin-top:var(--sp-3)}
  #app .theme-picker{grid-template-columns:repeat(2,minmax(0,1fr));gap:var(--sp-2)}
  #app .theme-swatch{height:48px}
  #app .profile-fields{grid-template-columns:1fr}
  #app .profile-fields .wide{grid-column:auto}
  #app .paper>.result-num{font-size:3rem}
}
@media (hover:none){
  #app a.card:hover,#app .category-card:hover,#app .book-card:hover .book-cover{transform:none}
}
@media (prefers-reduced-motion:reduce){
  #app *,#app *::before,#app *::after{transition:none!important;animation:none!important}
  #app a.card:hover,#app .category-card:hover,#app .book-card:hover .book-cover,#app .primary:hover{transform:none}
}