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.exam-focus-panel{display:grid;grid-template-columns:minmax(0,.68fr) minmax(0,1.32fr);gap:18px;margin:0 0 16px;padding:20px;background:#fff;border:1px solid #f2c891;border-left:4px solid var(--amber);border-radius:var(--radius);box-shadow:var(--shadow)}.exam-focus-panel h2{margin-bottom:8px}.exam-focus-panel p:not(.eyebrow){margin:0;color:var(--muted)}.exam-focus-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:10px}.exam-focus-grid article{display:grid;gap:4px;padding:12px;border:1px solid #fde2bd;border-radius:7px;background:#fffaf0}.exam-focus-grid strong{color:#7c2d12}.exam-focus-grid span{color:#475569;font-size:14px;line-height:1.55}.exam-focus-card{border-color:#f2c891;background:linear-gradient(180deg,#fffaf0,#fbfdff 120px)}.exam-focus-tags{display:flex;flex-wrap:wrap;gap:6px;margin:-4px 0 10px}.exam-focus-tags strong,.exam-focus-tags span{min-height:28px;display:inline-flex;align-items:center;border-radius:999px;padding:0 9px;font-size:13px;line-height:1}.exam-focus-tags strong{background:var(--amber);color:#fff}.exam-focus-tags span{background:#fff7ed;border:1px solid #fed7aa;color:#7c2d12}.visual-neural{min-height:150px;grid-template-columns:1fr 1fr 1fr 1fr;background:radial-gradient(circle at 18% 50%,rgba(29,78,216,.14),transparent 12%),radial-gradient(circle at 45% 28%,rgba(15,118,110,.14),transparent 10%),radial-gradient(circle at 45% 70%,rgba(15,118,110,.14),transparent 10%),radial-gradient(circle at 72% 50%,rgba(180,83,9,.14),transparent 12%),linear-gradient(135deg,#eff6ff,#f8fafc)}.visual-neural::before{left:16%;right:18%;top:36%;height:30%;border-top:2px solid rgba(15,118,110,.45);border-bottom:2px solid rgba(15,118,110,.45);transform:skewX(-18deg)}.visual-neural::after{right:12%;top:28%;width:34px;height:34px;border-radius:50%;border:2px solid var(--amber);box-shadow:-42px 28px 0 -1px rgba(180,83,9,.38);animation:bpFlow 2.6s ease-in-out infinite}@keyframes bpFlow{0%,100%{transform:translateX(0);opacity:.65}50%{transform:translateX(-24px);opacity:1}}
@media(max-width:860px){.exam-focus-panel{grid-template-columns:1fr;padding:16px}.exam-focus-grid{grid-template-columns:1fr}}
.resource-list{display:block}.resource-note{display:grid;place-items:center;min-height:360px;padding:22px;border:1px dashed #b7c8d8;border-radius:7px;background:var(--surface-2);color:var(--muted);text-align:center}.all-subjects{grid-template-columns:repeat(auto-fit,minmax(280px,1fr))}
.pdf-viewer .mobile-pdf-list.resource-list{display:none}

.self-check-box{border-color:rgba(15,118,110,.22);border-left-color:var(--blue);border-radius:10px;background:var(--blue-soft)}
.exam-focus-panel{background:var(--surface);border-color:rgba(251,146,60,.32);border-left-color:var(--amber);box-shadow:var(--shadow);backdrop-filter:blur(18px);-webkit-backdrop-filter:blur(18px)}
.exam-focus-grid article{border-color:rgba(251,146,60,.28);border-radius:10px;background:var(--amber-soft)}
.exam-focus-grid strong,.exam-focus-tags span{color:#7c2d12}.theme-dark .exam-focus-grid strong,.theme-dark .exam-focus-tags span{color:#fde68a}
.exam-focus-grid span{color:var(--muted)}
.exam-focus-card{border-color:rgba(251,146,60,.35);background:linear-gradient(180deg,var(--amber-soft),var(--surface-solid) 150px)}
.exam-focus-tags strong{background:var(--amber);color:#fff}.exam-focus-tags span{background:var(--amber-soft);border-color:rgba(251,146,60,.32)}
.resource-note{border-color:var(--line-strong);border-radius:10px;background:var(--surface-2);color:var(--muted)}
.mobile-reader-controls button{border-color:var(--line);border-radius:10px;background:var(--surface-solid);color:var(--teal-dark)}
.mobile-reader-controls span{border-color:var(--line);border-radius:10px;background:var(--surface-2);color:var(--text)}
.mobile-reader-canvas{border-color:var(--line);border-radius:10px;background:var(--surface-2)}
.mobile-reader-note{color:var(--muted)}
.visual-bayes,.visual-cnn-stack,.visual-detection,.visual-overfit,.visual-neural,.visual-stereo,.visual-svm{background:linear-gradient(135deg,var(--teal-soft),var(--surface-2))}
.visual-bayes span:nth-child(3),.visual-overfit span:nth-child(2){background:var(--blue-soft)}
.visual-bayes span:nth-child(4),.visual-overfit span:nth-child(3){background:var(--amber-soft)}

@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*,*::before,*::after{animation:none!important;transition:none!important}}
@media(max-width:1120px){.reader-layout{grid-template-columns:minmax(290px,34vw) minmax(0,1fr)}#pdf-frame{min-height:600px}}
@media(max-width:860px){body{background:var(--bg);font-size:15px}.site-header{display:grid;grid-template-columns:minmax(0,1fr) auto;align-items:center;gap:8px;padding:10px 14px}.site-brand{min-height:40px}.theme-toggle{grid-column:2;grid-row:1}.top-nav{grid-column:1/-1;width:100%;padding-bottom:4px}.home-hero,.home-about,.upcoming-grid,.subject-grid,.subject-header{grid-template-columns:1fr}.mobile-tabs{top:104px;background:var(--surface);border-radius:12px;backdrop-filter:blur(16px);-webkit-backdrop-filter:blur(16px)}.tab-button{border-color:var(--line);border-radius:10px;background:var(--surface-solid);color:var(--muted);font-weight:700}.tab-button.is-active{background:var(--teal);border-color:var(--teal);color:#fff}.outline-pane,.pdf-viewer{background:var(--surface);box-shadow:var(--shadow-soft)}.study-card{box-shadow:none}.concept-visual span:not(:last-child)::after{display:none}#pdf-frame{height:62vh;min-height:430px}.pdf-actions a,.pdf-actions button{min-height:44px}}
@media(max-width:520px){main{width:min(100% - 20px,720px);padding-bottom:48px}.home-hero{padding:20px}.site-preview{display:none}.subject-link{grid-template-columns:48px minmax(0,1fr);gap:14px}.subject-arrow{display:none}.subject-copy strong{font-size:18px}.subject-copy span{font-size:14px}.home-about{grid-template-columns:1fr;padding:18px}.subject-header{padding:18px}.flow-strip{margin-bottom:12px}.outline-pane,.pdf-viewer{padding:10px}.viewer-toolbar a{width:100%}.pdf-switcher button{max-width:168px}.mobile-reader-canvas{padding:6px}}

/* Final reader sizing: keep the outline compact and give the PDF the room. */
@media(min-width:861px){
  .reader-layout{
    grid-template-columns:minmax(260px,min(25%,340px)) minmax(0,1fr);
  }
  .outline-pane,
  .pdf-viewer,
  .study-card,
  .card-main,
  .pdf-switcher{
    min-width:0;
  }
  .outline-pane{
    padding:14px;
  }
  .study-guide{
    gap:12px;
  }
  .study-card{
    display:block;
    padding:14px;
  }
  .study-card .concept-visual{
    grid-template-columns:repeat(2,minmax(0,1fr));
    min-height:96px;
    margin-top:12px;
  }
  .study-card .concept-visual span{
    min-height:42px;
    font-size:12px;
  }
  .study-card .concept-visual span::after{
    display:none;
  }
  .card-grid,
  .explain-row{
    grid-template-columns:1fr;
    gap:10px;
  }
  .card-grid section,
  .hard-box,
  .example-box{
    padding:11px;
    font-size:14px;
  }
  .card-source{
    font-size:12px;
  }
  .summary{
    font-size:14px;
  }
  #pdf-frame{
    min-height:700px;
  }
}

@media(max-width:520px){
  .subject-header p,
  .subject-copy span{
    overflow-wrap:anywhere;
  }
  .subject-stats{
    grid-template-columns:repeat(3,minmax(0,1fr));
    gap:8px;
  }
  .subject-stats span{
    min-height:62px;
    padding:8px 4px;
    font-size:12px;
  }
  .subject-stats strong{
    font-size:20px;
  }
}

@media(max-width:860px){
  .pdf-viewer .mobile-pdf-list.resource-list{
    display:block;
  }
  .pdf-viewer.pdfjs-enabled .mobile-pdf-list.resource-list{
    display:none;
  }
}