/* TheCodexes.com · USMLE Step 2 CK Online QBank (v3.2) — extends /styles.css tokens */
.qb {
  --em-bg: #E6F5EF;
  --em-bd: #B8E3D3;
  --em-theme: #0b4a3d;
  --amb: #9A6B12;
  --amb-bg: #FBF5E6;
  --amb-bd: #E8D3A6;
  --qb-font-scale: 1;
  background-color: #f8f6f0;
  background-image: linear-gradient(#f8f6f0b8, #f8f6f0b8), url('/assets/codex-hex.svg');
  background-size: auto, 41.57px 72px;
}
.qb[data-font-size="sm"] { --qb-font-scale: 0.92; }
.qb[data-font-size="lg"] { --qb-font-scale: 1.12; }

/* Hero */
.qb-hero {
  position: relative;
  overflow: hidden;
  color: #fff;
  background: radial-gradient(1200px 500px at 85% -10%, rgba(201,242,228,.18), transparent 60%), linear-gradient(160deg, #12A884 0%, var(--emerald-d) 45%, var(--emerald-deep) 100%);
  padding: clamp(40px, 7vw, 80px) var(--gut) clamp(36px, 6vw, 60px);
}
.qb-hero .in {
  max-width: 1180px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1.15fr .85fr;
  gap: clamp(24px, 4vw, 56px);
  align-items: center;
}
.qb-eyebrow {
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: .18em;
  text-transform: uppercase;
  opacity: .92;
  display: flex;
  align-items: center;
  gap: 10px;
}
.qb-eyebrow:before {
  content: "";
  width: 28px;
  height: 1px;
  background: currentColor;
  opacity: .7;
}
.qb-hero h1 {
  font-family: var(--display);
  font-weight: 400;
  font-size: clamp(42px, 6.6vw, 80px);
  line-height: .98;
  margin: 18px 0;
  letter-spacing: -.01em;
}
.qb-hero h1 i { font-style: italic; }
.qb-hero p.lede {
  font-family: var(--serif);
  font-size: clamp(17px, 1.55vw, 19px);
  line-height: 1.55;
  max-width: 580px;
  opacity: .95;
  margin: 0 0 22px;
}
.qb-cta { display: flex; flex-wrap: wrap; gap: 10px; }
.qb-btn {
  appearance: none;
  border: 0;
  cursor: pointer;
  font-family: var(--sans);
  font-weight: 700;
  font-size: 15px;
  border-radius: 999px;
  padding: 13px 22px;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  text-decoration: none;
  transition: transform .15s var(--ease), box-shadow .15s;
}
.qb-btn:hover:not(:disabled) { transform: translateY(-1px); }
.qb-btn:active:not(:disabled) { transform: translateY(0) scale(.98); }
.qb-btn:disabled { opacity: .52; cursor: not-allowed; }
.qb-btn.pri { background: #fff; color: var(--emerald-dd); box-shadow: 0 8px 24px -8px rgba(0,0,0,.35); }
.qb-btn.gold { background: linear-gradient(180deg, #C9A23A, #A8842A); color: #fff; box-shadow: 0 8px 24px -10px rgba(120,90,20,.6); }
.qb-btn.ghost { background: rgba(255,255,255,.1); color: #fff; border: 1px solid rgba(255,255,255,.35); }
.qb-btn.line { background: #fff; color: var(--ink); border: 1px solid var(--line-2); }
.qb-btn.em { background: var(--emerald); color: #fff; }

.qb-stats { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; }
.qb-stat {
  border: 1px solid rgba(255,255,255,.22);
  background: rgba(255,255,255,.06);
  border-radius: 16px;
  padding: 16px 18px;
}
.qb-stat b {
  display: block;
  font-family: var(--display);
  font-weight: 400;
  font-size: clamp(32px, 3.8vw, 44px);
  line-height: 1;
}
.qb-stat span {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: .14em;
  text-transform: uppercase;
  opacity: .9;
}
.qb-free-note { margin-top: 14px; font-size: 13px; opacity: .9; font-family: var(--sans); }

.qb-wrap { max-width: 1180px; margin: 0 auto; padding: 0 var(--gut); }
.qb-sec { padding: clamp(32px, 5vw, 56px) 0; }
.qb-h2 { font-family: var(--display); font-weight: 400; font-size: clamp(32px, 4vw, 46px); color: var(--ink); margin: 0 0 6px; line-height: 1.05; }
.qb-sub { font-family: var(--serif); color: var(--slate); font-size: 17px; margin: 0 0 22px; max-width: 760px; }
.qb-kicker { font-family: var(--mono); font-size: 11.5px; letter-spacing: .16em; text-transform: uppercase; color: var(--emerald-d); margin-bottom: 8px; }

/* Connected Visual Companion Topic Banner */
.qb-vc-banner[hidden] { display: none !important; }
.qb-vc-banner {
  margin-top: 28px;
  background: linear-gradient(135deg, #f0faf6 0%, #ffffff 100%);
  border: 1.5px solid #0b4a3d;
  border-left: 6px solid #0b4a3d;
  border-bottom: 4px solid #0b4a3d;
  border-radius: 20px;
  padding: 24px 28px;
  box-shadow: var(--shadow-lg);
}
.qb-vc-banner-in {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 24px;
  flex-wrap: wrap;
}
.qb-vc-banner h2 {
  font-family: var(--display);
  font-weight: 400;
  font-size: clamp(26px, 3vw, 36px);
  color: var(--ink);
  margin: 4px 0 6px;
}
.qb-vc-banner p {
  font-family: var(--sans);
  font-size: 14.5px;
  color: var(--slate);
  margin: 0;
}
.qb-vc-banner-actions { display: flex; flex-wrap: wrap; gap: 10px; align-items: center; }

/* Launch Card */
.qb-launch {
  display: grid;
  grid-template-columns: 1.15fr .85fr;
  gap: clamp(24px, 4vw, 56px);
  align-items: center;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 24px;
  padding: clamp(24px, 4vw, 44px);
  box-shadow: var(--shadow-lg);
}
.qb-launch h3 { font: 400 clamp(28px, 3vw, 40px)/1.08 var(--display); color: var(--ink); margin: 0 0 12px; max-width: 560px; }
.qb-launch p { font: 400 17px/1.55 var(--serif); color: var(--slate); margin: 0 0 17px; max-width: 600px; }
.qb-launch-pills { display: flex; flex-wrap: wrap; gap: 8px; margin: 0 0 22px; }
.qb-launch-pills span {
  font: 700 11px var(--mono);
  letter-spacing: .04em;
  border: 1px solid var(--em-bd);
  background: #f2faf6;
  color: var(--emerald-d);
  padding: 8px 10px;
  border-radius: 999px;
}
.qb-launch-preview {
  min-height: 260px;
  display: flex;
  flex-direction: column;
  justify-content: center;
  border: 1px solid #e2d9c8;
  border-left: 4px solid #0b4a3d;
  border-bottom: 4px solid #0b4a3d;
  border-radius: 20px;
  padding: 28px;
  box-shadow: 0 20px 34px -24px rgba(15,34,58,.3);
  background: linear-gradient(150deg, #fffdf9, #f2eee6);
}
.qb-preview-q { font: 400 30px/1.12 var(--display); color: var(--ink); margin: 10px 0 18px; }
.qb-preview-rule { height: 1px; background: #d9cfbf; }
.qb-preview-answer { font: 400 16.5px/1.45 var(--serif); color: var(--slate); margin: 18px 0; }
.qb-preview-foot { font: 700 10px var(--mono); letter-spacing: .14em; color: var(--emerald-d); }
.qb-launch .qb-btn.line span { border-radius: 999px; background: var(--em-bg); padding: 1px 7px; }

/* Session Configurator (Whole Corpus vs Single Chapter + NBME Exam Weight Proportions) */
.qb-builder-box {
  background: #fff;
  border: 1px solid var(--em-bd);
  border-left: 4px solid #0b4a3d;
  border-bottom: 3px solid #0b4a3d;
  border-radius: 16px;
  padding: 16px 18px;
  margin: 0 0 18px;
  box-shadow: 0 8px 20px rgba(11,74,61,.06);
  display: grid;
  gap: 12px;
}
.qb-builder-row {
  display: grid;
  gap: 6px;
}
.qb-builder-row[hidden] { display: none !important; }
.qb-builder-lbl {
  font: 700 11px var(--mono);
  letter-spacing: .12em;
  text-transform: uppercase;
  color: #0b4a3d;
}
.qb-seg-group {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}
.qb-seg-btn {
  appearance: none;
  border: 1.5px solid var(--line-2);
  background: #fcfbf9;
  color: var(--ink-2);
  border-radius: 10px;
  padding: 9px 13px;
  font: 700 12.5px var(--sans);
  cursor: pointer;
  transition: background .12s, border-color .12s, color .12s, box-shadow .12s;
  flex: 1 1 210px;
  text-align: left;
}
.qb-seg-btn:hover {
  border-color: #0b4a3d;
  background: #f4faf7;
}
.qb-seg-btn.on {
  background: #0b4a3d;
  border-color: #0b4a3d;
  color: #fff;
  box-shadow: 0 4px 12px rgba(11,74,61,.2);
}
.qb-builder-select {
  width: 100%;
  padding: 10px 12px;
  border: 1.5px solid var(--em-bd);
  border-radius: 10px;
  background: #fff;
  color: var(--ink);
  font: 600 13.5px var(--sans);
  cursor: pointer;
}
.qb-builder-select:focus {
  outline: 2px solid #0b4a3d;
  outline-offset: 1px;
}
.qb-builder-summary {
  padding-top: 8px;
  border-top: 1px dashed var(--line-2);
  font: 500 12.5px/1.45 var(--sans);
  color: var(--slate);
}
.qb-builder-summary b { color: #0b4a3d; font-weight: 700; }

/* NBME Weight Distribution Preview Bars */
.qb-weight-bars {
  display: grid;
  gap: 7px;
  margin: 14px 0;
}
.qb-wbar-row {
  display: grid;
  grid-template-columns: 148px 1fr 48px;
  align-items: center;
  gap: 8px;
  font: 600 11.5px var(--sans);
  color: var(--ink-2);
}
.qb-wbar-lbl {
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.qb-wbar-track {
  height: 8px;
  background: #e5dfd3;
  border-radius: 999px;
  overflow: hidden;
}
.qb-wbar-fill {
  height: 100%;
  background: linear-gradient(90deg, #0b4a3d, #178269);
  border-radius: 999px;
}
.qb-wbar-pct {
  font: 700 11px var(--mono);
  color: #0b4a3d;
  text-align: right;
}

/* Search & Chapter Grid */
.qb-deck-search {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: 16px 18px;
  margin-bottom: 18px;
  box-shadow: var(--shadow);
}
.qb-deck-search label {
  display: block;
  font: 700 12px var(--mono);
  letter-spacing: .08em;
  text-transform: uppercase;
  color: var(--emerald-d);
  margin-bottom: 8px;
}
.qb-search-row { display: flex; gap: 10px; }
.qb-search-row input {
  flex: 1;
  padding: 12px 14px;
  border: 1px solid var(--line-2);
  border-radius: 12px;
  font: 15.5px var(--sans);
}
.qb-search-row button {
  padding: 0 16px;
  border: 1px solid var(--line-2);
  border-radius: 12px;
  background: var(--cream);
  font: 700 13px var(--sans);
  cursor: pointer;
}
#deckSearchStatus { margin: 8px 0 0; font: 13px var(--sans); color: var(--slate); }

.qb-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); gap: 14px; }
.qb-ch {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: 18px 18px 15px;
  box-shadow: var(--shadow);
  cursor: pointer;
  transition: transform .15s var(--ease), box-shadow .15s;
  text-align: left;
}
.qb-ch:hover { transform: translateY(-2px); box-shadow: var(--shadow-lg); }
.qb-ch .n, .qb-ch .num { font-family: var(--mono); font-size: 11px; letter-spacing: .14em; color: var(--emerald-d); }
.qb-ch .top { display: flex; justify-content: space-between; align-items: center; gap: 8px; }
.qb-ch .cnt { font-family: var(--mono); font-size: 11px; color: var(--slate); }
.qb-ch h3 { font-family: var(--serif); font-weight: 600; font-size: 18px; line-height: 1.3; margin: 6px 0 10px; color: var(--ink); }
.qb-ch .meta { display: flex; gap: 10px; flex-wrap: wrap; font-family: var(--sans); font-size: 12.5px; color: var(--slate); }
.qb-ch .meta b { color: var(--ink); }
.qb-ch-actions { margin-top: 12px; display: flex; gap: 8px; flex-wrap: wrap; }
.qb-ch-btn {
  appearance: none;
  border-radius: 999px;
  padding: 7px 13px;
  font: 700 12px var(--sans);
  cursor: pointer;
  transition: transform .12s, background .12s;
}
.qb-ch-btn.pri { background: #0b4a3d; color: #fff; border: 1px solid #0b4a3d; }
.qb-ch-btn.pri:hover { background: var(--emerald); border-color: var(--emerald); }
.qb-ch-btn.line { background: #fff; color: #0b4a3d; border: 1px solid var(--em-bd); }
.qb-ch-btn.line:hover { background: var(--em-bg); }
.qb-ch.open-ch { grid-column: 1 / -1; cursor: default; border-left: 4px solid #0b4a3d; }

.qb-ch-topics {
  margin-top: 12px;
  border-top: 1px solid var(--line);
  padding-top: 10px;
}
.qb-ch-topics summary {
  font: 700 12px var(--mono);
  color: #0b4a3d;
  cursor: pointer;
  user-select: none;
}
.qb-topic-list, .qb-tl {
  margin-top: 10px;
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 8px 14px;
}
.qb-topic-row, .qb-topic-item {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 10px;
  padding: 10px 12px;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: #fcfbf9;
  font-family: var(--sans);
  font-size: 13.5px;
}
.qb-topic-row.hl, .qb-topic-item.qb-topic-highlight {
  background: #E6F5EF;
  border-color: #0b4a3d;
  box-shadow: 0 0 0 1px #0b4a3d;
}
.qb-topic-code { display: block; font: 700 10.5px var(--mono); color: #0b4a3d; letter-spacing: .06em; }
.qb-topic-name { margin: 2px 0 3px; font: 600 13.5px/1.3 var(--sans); color: var(--ink); }
.qb-topic-sub { font: 500 11px var(--mono); color: var(--slate); }
.qb-topic-info { min-width: 0; flex: 1; }
.qb-topic-info strong { display: block; color: var(--ink); font-size: 14px; line-height: 1.3; }
.qb-topic-info small { color: var(--slate); font-family: var(--mono); font-size: 11px; }
.qb-topic-btns, .qb-topic-actions { display: flex; gap: 6px; flex: none; align-items: center; flex-wrap: wrap; }
.qb-topic-play, .qb-tbtn.play {
  appearance: none;
  border: 1px solid #0b4a3d;
  background: #0b4a3d;
  color: #fff;
  border-radius: 999px;
  padding: 6px 11px;
  font: 700 11.5px var(--sans);
  cursor: pointer;
  white-space: nowrap;
}
.qb-topic-play:hover, .qb-tbtn.play:hover { background: var(--emerald); border-color: var(--emerald); }
.qb-tbtn.exam {
  appearance: none;
  border: 1px solid #B8862B;
  background: var(--amb-bg);
  color: #8A5D0B;
  border-radius: 999px;
  padding: 5px 10px;
  font: 700 11px var(--mono);
  cursor: pointer;
  white-space: nowrap;
}
.qb-tbtn.exam:hover { background: #f5e6c4; }
.qb-topic-vc, .qb-tbtn.vc {
  color: #0b4a3d;
  border: 1px solid var(--em-bd);
  background: #fff;
  border-radius: 999px;
  padding: 5px 10px;
  font: 700 11px var(--mono);
  text-decoration: none;
  white-space: nowrap;
}
.qb-topic-vc:hover, .qb-tbtn.vc:hover { background: var(--em-bg); }

/* Premium section */
.qb-prem { display: grid; grid-template-columns: 1.1fr .9fr; gap: 24px; align-items: stretch; }
.qb-feat { background: #fff; border: 1px solid var(--line); border-radius: 18px; padding: 22px 24px; box-shadow: var(--shadow); }
.qb-feat ul { margin: 0; padding: 0; list-style: none; display: grid; gap: 12px; font-family: var(--serif); font-size: 16.5px; line-height: 1.45; }
.qb-feat li { padding-left: 28px; position: relative; }
.qb-feat li:before { content: "✓"; position: absolute; left: 0; top: 0; color: var(--emerald); font-weight: 700; font-family: var(--sans); }
.qb-buy { background: #fffefa; color: #162b27; border: 1.5px solid #0b4a3d; border-radius: 18px; padding: 26px; display: flex; flex-direction: column; gap: 12px; box-shadow: -4px 4px 0 rgba(22,43,39,.10); }
.qb-buy h3 { font-family: var(--display); font-weight: 400; font-size: 34px; margin: 0; line-height: 1.05; }
.qb-buy p { margin: 0; font-family: var(--serif); opacity: .92; }
.qb-buy .fine { font-size: 12.5px; opacity: .78; font-family: var(--sans); line-height: 1.5; }

/* NBME Split-Pane Question Player Modal — Calm, Distraction-Free Neutral Palette */
.qb-player-modal[hidden] { display: none !important; }
.qb-player-modal {
  position: fixed;
  inset: 0;
  z-index: 75;
  background-color: #f8f6f0;
  background-image: linear-gradient(#f8f6f0b8, #f8f6f0b8), url('/assets/codex-hex.svg');
  background-size: auto, 41.57px 72px;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: clamp(8px, 1.8vw, 22px);
}
.qb-player-shell {
  width: min(1440px, 100%);
  height: min(94dvh, 980px);
  display: flex;
  flex-direction: column;
  background: #fff;
  border: 1.5px solid #d6d0c4;
  border-radius: 22px;
  box-shadow: 0 20px 60px rgba(15, 23, 42, .12);
  overflow: hidden;
}
.qb-player-shell.font-sm { --qb-font-scale: 0.92; }
.qb-player-shell.font-lg { --qb-font-scale: 1.12; }

.qb-exam-bar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 14px;
  padding: 11px 20px;
  background: #f3f4f6;
  color: #374151;
  border-bottom: 1px solid #e5e7eb;
  flex: none;
}
.qb-exam-left { display: flex; align-items: center; gap: 10px; min-width: 0; }
.qb-exam-badge {
  background: #ffffff;
  border: 1px solid #d1d5db;
  color: #374151;
  padding: 5px 12px;
  border-radius: 999px;
  font: 700 12px var(--mono);
  letter-spacing: .04em;
  white-space: nowrap;
}
.qb-mode-pill {
  padding: 5px 10px;
  border-radius: 999px;
  font: 700 10.5px var(--mono);
  letter-spacing: .08em;
  text-transform: uppercase;
  background: #e5e7eb;
  border: 1px solid #d1d5db;
  color: #374151;
  white-space: nowrap;
}
.qb-player-shell[data-study-mode="exam"] .qb-mode-pill {
  background: #e5e7eb;
  border-color: #cbd5e1;
  color: #374151;
}
.qb-top-mode-switch {
  background: #e5e7eb;
  border: 1px solid #d1d5db;
  padding: 2px;
  border-radius: 999px;
  display: inline-flex;
}
.qb-top-mode-switch .qb-mode-btn {
  color: #6b7280;
  padding: 4px 11px;
  font: 600 11.5px var(--sans);
}
.qb-top-mode-switch .qb-mode-btn.on {
  background: #ffffff;
  color: #1f2937;
  box-shadow: 0 1px 3px rgba(0, 0, 0, .08);
}
.qb-exam-titles { min-width: 0; }
.qb-exam-kicker { font: 700 10.5px var(--mono); letter-spacing: .12em; color: #6b7280; text-transform: uppercase; }
.qb-exam-titles h2 {
  font: 600 15.5px/1.25 var(--sans);
  margin: 2px 0 0;
  color: #1f2937;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.qb-exam-tools { display: flex; align-items: center; gap: 8px; flex-wrap: wrap; }
.qb-timer {
  font: 700 12.5px var(--mono);
  background: #ffffff;
  color: #374151;
  border: 1px solid #d1d5db;
  padding: 5px 10px;
  border-radius: 8px;
  white-space: nowrap;
}
.qb-timer.warn { background: #f3f4f6; color: #4b5563; border-color: #9ca3af; }
.qb-timer.crit { background: #fff5f5; color: #991b1b; border-color: #f5d0d0; }
.qb-tool-btn {
  appearance: none;
  border: 1px solid #d1d5db;
  background: #ffffff;
  color: #374151;
  border-radius: 999px;
  padding: 5px 12px;
  font: 600 12px var(--sans);
  cursor: pointer;
}
.qb-tool-btn:hover, .qb-tool-btn[aria-expanded="true"], .qb-tool-btn[aria-pressed="true"] {
  background: #e5e7eb;
  color: #111827;
  border-color: #9ca3af;
}
.qb-end-block-btn {
  background: #e5e7eb;
  border-color: #cbd5e1;
  color: #1f2937;
}
.qb-end-block-btn:hover {
  background: #d1d5db;
  color: #111827;
}
.qb-exam-close {
  width: 34px;
  height: 34px;
  border-radius: 50%;
  border: 1px solid #d1d5db;
  background: #ffffff;
  color: #4b5563;
  font: 400 20px var(--sans);
  cursor: pointer;
}
.qb-exam-close:hover { background: #e5e7eb; color: #111827; }

.qb-siblings[hidden],
.qb-end-block-btn[hidden],
.qb-exam-strip[hidden],
.qb-exam-summary[hidden],
.qb-family-banner[hidden],
.qb-meta-drawer[hidden],
.qb-collapsible-meta[hidden],
#collapsibleMetaDrawer[hidden],
#metaToggleBtn[hidden] {
  display: none !important;
}
/* In Exam Mode: do NOT even show the collapsible metadata option or drawer */
.qb-player-shell[data-study-mode="exam"] #metaToggleBtn,
.qb-player-shell[data-study-mode="exam"] #collapsibleMetaDrawer {
  display: none !important;
}
.qb-meta-drawer,
.qb-collapsible-meta {
  background: #f8f9fa;
  border-bottom: 1px solid #e5e7eb;
  padding: 10px 20px 12px;
  display: grid;
  gap: 8px;
  flex: none;
}
.qb-meta-drawer-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
}
.qb-meta-drawer-info {
  display: flex;
  align-items: center;
  gap: 10px;
  min-width: 0;
  flex-wrap: wrap;
}
.qb-meta-drawer-info .qb-exam-kicker {
  color: #6b7280;
}
.qb-meta-drawer-title {
  margin: 0;
  font: 600 15px/1.25 var(--sans);
  color: #1f2937;
}
.qb-siblings {
  display: inline-flex;
  gap: 4px;
  background: #eef0f2;
  padding: 3px;
  border-radius: 999px;
  border: 1px solid #d1d5db;
}
.qb-siblings button {
  border: 0;
  background: transparent;
  color: #4b5563;
  font: 700 11px var(--mono);
  padding: 4px 9px;
  border-radius: 999px;
  cursor: pointer;
}
.qb-siblings button.on { background: #d1d5db; color: #1f2937; }

.qb-subbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
  padding: 6px 0 0;
  border-top: 1px dashed #e5e7eb;
  flex: none;
  flex-wrap: wrap;
}
.qb-subbar-left, .qb-subbar-right { display: flex; align-items: center; gap: 8px; flex-wrap: wrap; }
.qb-mode-switch {
  display: inline-flex;
  background: #e5e7eb;
  padding: 3px;
  border-radius: 999px;
  border: 1px solid #d1d5db;
}
.qb-mode-btn {
  appearance: none;
  border: 0;
  background: transparent;
  color: #6b7280;
  font: 600 11.5px var(--sans);
  padding: 5px 12px;
  border-radius: 999px;
  cursor: pointer;
  transition: background .15s, color .15s;
}
.qb-mode-btn.on {
  background: #ffffff;
  color: #1f2937;
  box-shadow: 0 1px 3px rgba(0,0,0,.08);
}
.qb-subbar select {
  padding: 6px 10px;
  border: 1px solid #d1d5db;
  border-radius: 8px;
  background: #fff;
  font: 600 12.5px var(--sans);
  color: #374151;
  max-width: 240px;
}
.qb-hint-pill { font: 500 11.5px var(--sans); color: #6b7280; }
.qb-sub-btn {
  border: 1px solid #d1d5db;
  background: #fff;
  color: #374151;
  border-radius: 8px;
  padding: 5px 10px;
  font: 600 12px var(--sans);
  cursor: pointer;
}
.qb-sub-btn:hover { background: #f3f4f6; }
.qb-session-score {
  font: 700 12px var(--mono);
  color: #374151;
  background: #eef0f2;
  border: 1px solid #d1d5db;
  padding: 5px 11px;
  border-radius: 999px;
}

/* Exam Mode 1..20 Question Navigator Strip */
.qb-exam-strip {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 8px 20px;
  background: #f8f9fa;
  border-bottom: 1px solid #e5e7eb;
  overflow-x: auto;
  flex: none;
}
.qb-exam-strip-lbl {
  font: 700 10.5px var(--mono);
  letter-spacing: .1em;
  text-transform: uppercase;
  color: #6b7280;
  margin-right: 4px;
  white-space: nowrap;
}
.qb-exam-qpill {
  appearance: none;
  border: 1px solid #d1d5db;
  background: #fff;
  color: #374151;
  border-radius: 8px;
  min-width: 34px;
  height: 30px;
  padding: 0 6px;
  font: 600 11.5px var(--mono);
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 3px;
  transition: border-color .12s, background .12s;
}
.qb-exam-qpill:hover { border-color: #9ca3af; background: #f3f4f6; }
.qb-exam-qpill.cur {
  border-color: #6b7280;
  background: #f3f4f6;
  font-weight: 700;
}
.qb-exam-qpill.answered {
  background: #e5e7eb;
  border-color: #9ca3af;
  color: #1f2937;
}
.qb-exam-qpill.graded-ok {
  background: #f3f4f6;
  border-color: #9ca3af;
  color: #1f2937;
}
.qb-exam-qpill.graded-bad {
  background: #fff5f5;
  border-color: #f5d0d0;
  color: #991b1b;
}

/* Post-Exam Block Summary Bar */
.qb-exam-summary {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
  padding: 12px 20px;
  background: #f8f9fa;
  border-bottom: 1px solid #d1d5db;
  flex: none;
  flex-wrap: wrap;
}
.qb-exam-summary-main {
  display: flex;
  align-items: center;
  gap: 14px;
  flex-wrap: wrap;
}
.qb-exam-score-badge {
  background: #e5e7eb;
  color: #1f2937;
  border: 1px solid #cbd5e1;
  padding: 6px 14px;
  border-radius: 999px;
  font: 700 13px var(--mono);
}
.qb-exam-summary-meta {
  font: 500 13px var(--sans);
  color: #374151;
}
.qb-exam-summary-actions {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

/* Split-Pane Workspace */
.qb-workspace {
  position: relative;
  flex: 1;
  min-height: 0;
  display: grid;
  grid-template-columns: 1.05fr 0.95fr;
  background: #fcfbf8;
  overflow: hidden;
  -webkit-user-select: text;
  user-select: text;
}
.qb-wm-layer {
  position: absolute;
  inset: -40%;
  pointer-events: none;
  z-index: 4;
  opacity: .028;
  font: 700 14px var(--mono);
  color: #6b7280;
  transform: rotate(-22deg);
  white-space: pre;
  line-height: 3.4;
  letter-spacing: .08em;
  user-select: none;
}
.qb-forensic-layer {
  position: absolute;
  inset: 0;
  pointer-events: none;
  z-index: 3;
}
.qb-pane {
  position: relative;
  z-index: 2;
  overflow-y: auto;
  overscroll-behavior: contain;
  padding: clamp(18px, 2.4vw, 30px);
}
.qb-pane-stem {
  border-right: 1px solid #e5e7eb;
  background: #ffffff;
}
.qb-pane-options {
  background: #fafaf9;
}

.qb-meta-strip {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-bottom: 0;
}
.qb-pill, .qb-meta-pill {
  font: 600 10.5px var(--mono);
  letter-spacing: .06em;
  text-transform: uppercase;
  padding: 4px 9px;
  border-radius: 999px;
  background: #f3f4f6;
  color: #4b5563;
  border: 1px solid #e5e7eb;
}
.qb-pill.dark, .qb-meta-pill.em { background: #e5e7eb; color: #1f2937; border-color: #d1d5db; }
.qb-pill.gold, .qb-meta-pill.gold { background: #f3f4f6; color: #4b5563; border-color: #e5e7eb; }

/* Tutor Mode Concept Family Banner (Calm Light Grey inside Collapsible Drawer) */
.qb-family-banner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
  margin-bottom: 4px;
  padding: 8px 12px;
  background: #f3f4f6;
  border: 1px solid #e5e7eb;
  border-left: 3px solid #9ca3af;
  border-radius: 10px;
  font: 500 12px var(--sans);
  color: #374151;
}
.qb-family-banner b { font-family: var(--mono); color: #1f2937; }
.qb-family-chips { display: inline-flex; gap: 5px; flex-wrap: wrap; }
.qb-family-chip {
  border: 1px solid #d1d5db;
  background: #fff;
  color: #4b5563;
  border-radius: 999px;
  padding: 3px 9px;
  font: 600 11px var(--mono);
  cursor: pointer;
}
.qb-family-chip.on {
  background: #e5e7eb;
  border-color: #9ca3af;
  color: #1f2937;
}

.qb-stem-body {
  font-family: "Times New Roman", Georgia, var(--serif);
  font-size: calc(18.5px * var(--qb-font-scale));
  line-height: 1.66;
  color: #1f2937;
  display: grid;
  gap: 16px;
}
.qb-stem-body p { margin: 0; }
.qb-stem-para.qb-para-history {
  padding-bottom: 2px;
}
.qb-stem-para.qb-para-findings {
  padding-top: 14px;
  border-top: 1px solid #e5e7eb;
}
.qb-stem-body mark.qb-hl {
  background: #fef08a;
  color: inherit;
  padding: 0 2px;
  border-radius: 3px;
  cursor: pointer;
}
.qb-stem-body .qb-clue-span {
  border-bottom: 1.5px solid #9ca3af;
  background: #f3f4f6;
  padding: 0 2px;
  border-radius: 3px;
}

.qb-blocks-area { display: none; }

.qb-lead-in {
  margin-top: 16px;
  padding-top: 14px;
  border-top: 1px solid #e5e7eb;
  font-family: "Times New Roman", Georgia, var(--serif);
  font-weight: 700;
  font-size: calc(19px * var(--qb-font-scale));
  line-height: 1.45;
  color: #111827;
}

/* Answer Choices — Calm Light Grey & Very Light Red for Wrong Option */
.qb-options-head {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 10px;
  font: 600 11.5px var(--mono);
  text-transform: uppercase;
  letter-spacing: .08em;
  color: #6b7280;
}
.qb-options-list { display: grid; gap: 10px; }
.qb-opt, .qb-opt-row {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  background: #fff;
  border: 1px solid #e5e7eb;
  border-radius: 12px;
  padding: 12px 14px;
  cursor: pointer;
  transition: border-color .12s, background .12s;
}
.qb-opt:hover:not(.graded), .qb-opt-row:hover:not(.correct-ans):not(.wrong-ans) {
  border-color: #cbd5e1;
  background: #f8f9fa;
}
.qb-opt.selected, .qb-opt-row.selected {
  border-color: #9ca3af;
  background: #f3f4f6;
}
.qb-opt.struck .qb-opt-text, .qb-opt-row.struck .qb-opt-text {
  text-decoration: line-through;
  opacity: .42;
}
.qb-opt.correct, .qb-opt-row.correct-ans {
  border-color: #cbd5e1;
  border-left: 4px solid #9ca3af;
  background: #f3f4f6;
}
.qb-opt.wrong-selected, .qb-opt-row.wrong-ans {
  border-color: #f5d0d0;
  border-left: 4px solid #e5a0a0;
  background: #fff5f5;
}
.qb-opt-letter {
  width: 28px;
  height: 28px;
  border-radius: 50%;
  border: 1px solid #d1d5db;
  background: #f9fafb;
  display: grid;
  place-items: center;
  font: 700 13px var(--mono);
  color: #374151;
  flex: none;
  margin-top: 1px;
}
.qb-opt.selected .qb-opt-letter, .qb-opt-row.selected .qb-opt-letter {
  background: #e5e7eb;
  color: #111827;
  border-color: #9ca3af;
}
.qb-opt.correct .qb-opt-letter, .qb-opt-row.correct-ans .qb-opt-letter {
  background: #e5e7eb;
  color: #111827;
  border-color: #9ca3af;
}
.qb-opt.wrong-selected .qb-opt-letter, .qb-opt-row.wrong-ans .qb-opt-letter {
  background: #fee2e2;
  color: #991b1b;
  border-color: #f5d0d0;
}
.qb-opt-text {
  flex: 1;
  font-family: "Times New Roman", Georgia, var(--serif);
  font-size: calc(17.5px * var(--qb-font-scale));
  line-height: 1.45;
  color: #1f2937;
}
.qb-opt-tag {
  font: 600 10.5px var(--mono);
  padding: 3px 8px;
  border-radius: 999px;
  white-space: nowrap;
}
.qb-opt-tag.ok { background: #e5e7eb; color: #374151; }
.qb-opt-tag.bad { background: #fee2e2; color: #991b1b; }
.qb-opt-strike {
  border: 1px solid #e5e7eb;
  background: #f9fafb;
  color: #6b7280;
  border-radius: 6px;
  width: 26px;
  height: 26px;
  font: 700 13px var(--mono);
  cursor: pointer;
  flex: none;
}
.qb-opt-strike:hover { background: #e5e7eb; color: #1f2937; }

/* Submit Box */
.qb-submit-box {
  margin-top: 16px;
  background: #ffffff;
  border: 1px solid #e5e7eb;
  border-radius: 14px;
  padding: 14px 16px;
}
.qb-conf-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 10px;
  font: 600 12.5px var(--sans);
  color: #6b7280;
}
.qb-conf-btns { display: inline-flex; gap: 6px; }
.qb-conf-btns button {
  border: 1px solid #d1d5db;
  background: #fff;
  color: #4b5563;
  border-radius: 999px;
  padding: 4px 11px;
  font: 600 11.5px var(--sans);
  cursor: pointer;
}
.qb-conf-btns button.on {
  background: #e5e7eb;
  border-color: #9ca3af;
  color: #1f2937;
}
.qb-submit-actions { display: grid; gap: 8px; }
.qb-submit-btn {
  width: 100%;
  justify-content: center;
  background: #0b4a3d !important;
  color: #ffffff !important;
  border: 2px solid #07352b !important;
  font-weight: 800 !important;
  box-shadow: 0 0 0 3px rgba(11, 74, 61, 0.22), -3px 5px 14px rgba(11, 74, 61, 0.26) !important;
}
.qb-submit-btn:hover:not(:disabled) {
  background: #093d32 !important;
  transform: translateY(-1px);
}
.qb-submit-btn[hidden] { display: none !important; }
.qb-lease-status {
  margin: 8px 0 0;
  font: 500 11px var(--mono);
  color: #6b7280;
  text-align: center;
}

/* Post-Submit Rationale Boxes — Calm Light Grey & Very Light Red for Wrong Verdict */
.qb-rationale-area {
  margin-top: 18px;
  display: grid;
  gap: 14px;
  animation: qbin .2s ease-out;
}
@keyframes qbin { from { opacity: 0; transform: translateY(4px); } to { opacity: 1; transform: none; } }

.qb-verdict, .qb-rat-banner {
  padding: 13px 16px;
  border-radius: 12px;
  font-family: var(--sans);
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
}
.qb-verdict.ok, .qb-rat-banner.ok {
  background: #f3f4f6;
  border: 1px solid #e5e7eb;
  border-left: 4px solid #9ca3af;
  color: #1f2937;
}
.qb-verdict.no, .qb-rat-banner.bad {
  background: #fff5f5;
  border: 1px solid #f5d0d0;
  border-left: 4px solid #e5a0a0;
  color: #7f1d1d;
}
.qb-rat-banner h3 { margin: 0 0 3px; font: 700 15.5px var(--sans); }
.qb-rat-banner p { margin: 0; font: 600 14px var(--serif); }
.qb-rat-meta { font: 600 11px var(--mono); opacity: .75; }

.qb-box, .qb-rat-card {
  background: #ffffff;
  border: 1px solid #e5e7eb;
  border-left: 4px solid #cbd5e1;
  border-bottom: 2px solid #e5e7eb;
  border-radius: 12px;
  padding: 14px 16px;
  box-shadow: 0 2px 6px rgba(0,0,0,.02);
}
.qb-box.pearl, .qb-rat-card.pearl {
  background: #f9fafb;
  border-color: #e5e7eb;
  border-left: 4px solid #cbd5e1;
  border-bottom: 2px solid #e5e7eb;
}
.qb-box-lbl, .qb-rat-kicker {
  font: 700 10.5px var(--mono);
  letter-spacing: .12em;
  text-transform: uppercase;
  color: #6b7280;
  margin-bottom: 6px;
}
.qb-box.pearl .qb-box-lbl, .qb-rat-card.pearl .qb-rat-kicker { color: #6b7280; }
.qb-box-text, .qb-rat-card p {
  margin: 0;
  font-family: "Times New Roman", Georgia, var(--serif);
  font-size: calc(17px * var(--qb-font-scale));
  line-height: 1.55;
  color: #1f2937;
}
.qb-dist-item, .qb-wrong-item {
  padding: 10px 12px;
  margin-top: 8px;
  border: 1px solid #e5e7eb;
  border-radius: 10px;
  background: #f9fafb;
  font-family: "Times New Roman", Georgia, var(--serif);
  font-size: calc(16px * var(--qb-font-scale));
  line-height: 1.5;
  color: #374151;
}
.qb-dist-item b, .qb-wrong-item b { font-family: var(--sans); font-size: 13.5px; color: #1f2937; margin-right: 4px; }
.qb-right-when {
  display: inline;
  color: #4b5563;
  font-style: italic;
}
.qb-right-when b {
  font-family: var(--sans);
  font-size: 12.5px;
  font-style: normal;
  color: #4b5563;
  margin-left: 4px;
  margin-right: 3px;
}

.qb-connected-tiles, .qb-rat-links {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
}
.qb-conn-tile, .qb-eco-link {
  display: block;
  text-decoration: none;
  background: #f9fafb;
  border: 1px solid #e5e7eb;
  border-left: 3px solid #cbd5e1;
  border-radius: 10px;
  padding: 10px 13px;
  font-family: var(--sans);
  font-size: 13px;
  color: #374151;
  transition: background .12s;
}
.qb-conn-tile:hover, .qb-eco-link:hover { background: #f3f4f6; }
.qb-conn-tile b, .qb-eco-link b { display: block; color: #1f2937; margin-top: 2px; font-size: 13px; }
.qb-conn-tile span, .qb-eco-link small { display: block; color: #6b7280; font: 700 10px var(--mono); letter-spacing: .08em; }

.qb-rat-refs {
  font-family: var(--sans);
  font-size: 12.5px;
  color: #6b7280;
  background: #fff;
  border: 1px solid #e5e7eb;
  border-radius: 12px;
  padding: 12px 16px;
}
.qb-rat-refs ol { margin: 6px 0 0; padding-left: 18px; }
.qb-rat-refs li { margin-bottom: 4px; }

/* Labs Drawer & Calculator Popover — Calm Light Grey */
.qb-labs-drawer[hidden], .qb-calc-pop[hidden], .qb-security-veil[hidden] { display: none !important; }
.qb-labs-drawer {
  position: absolute;
  top: 0;
  right: 0;
  bottom: 0;
  width: min(440px, 100%);
  background: #fff;
  border-left: 1.5px solid #d1d5db;
  box-shadow: -12px 0 32px rgba(0,0,0,.1);
  z-index: 20;
  display: flex;
  flex-direction: column;
}
.qb-labs-head {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 13px 18px;
  background: #f3f4f6;
  color: #1f2937;
  border-bottom: 1px solid #e5e7eb;
}
.qb-labs-head h3 { margin: 0; font: 700 14.5px var(--sans); color: #1f2937; }
.qb-labs-head button { border: 0; background: transparent; color: #4b5563; font-size: 22px; cursor: pointer; }
.qb-labs-search { padding: 10px 14px; border-bottom: 1px solid #e5e7eb; }
.qb-labs-search input { width: 100%; padding: 8px 12px; border: 1px solid #d1d5db; border-radius: 8px; font: 14px var(--sans); }
.qb-labs-tabs { display: flex; border-bottom: 1px solid #e5e7eb; background: #f9fafb; }
.qb-labs-tabs button {
  flex: 1;
  border: 0;
  background: transparent;
  padding: 9px 6px;
  font: 600 11.5px var(--sans);
  color: #6b7280;
  cursor: pointer;
  border-bottom: 2px solid transparent;
}
.qb-labs-tabs button.on { color: #1f2937; border-bottom-color: #6b7280; background: #fff; }
.qb-labs-body { flex: 1; overflow-y: auto; padding: 12px 16px; }
.qb-lab-row, .qb-lab-ref-row {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  padding: 7px 0;
  border-bottom: 1px solid #e5e7eb;
  font: 13px var(--sans);
  color: #374151;
}
.qb-lab-row span:last-child, .qb-lab-ref-row span:last-child { font-family: var(--mono); font-size: 12px; color: #374151; font-weight: 600; text-align: right; }

.qb-calc-pop {
  position: absolute;
  top: 14px;
  right: 20px;
  width: 260px;
  background: #fff;
  border: 1.5px solid #d1d5db;
  border-radius: 16px;
  box-shadow: 0 16px 40px rgba(0,0,0,.14);
  padding: 14px;
  z-index: 25;
}
.qb-calc-head { display: flex; justify-content: space-between; align-items: center; margin-bottom: 8px; }
.qb-calc-head h4 { margin: 0; font: 700 13px var(--mono); text-transform: uppercase; color: #374151; }
.qb-calc-head button { border: 0; background: transparent; font-size: 18px; color: #4b5563; cursor: pointer; }
#calcDisplay {
  width: 100%;
  padding: 10px;
  margin-bottom: 10px;
  border: 1px solid #d1d5db;
  border-radius: 8px;
  font: 700 18px var(--mono);
  text-align: right;
  background: #f9fafb;
  color: #1f2937;
}
.qb-calc-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 6px; }
.qb-calc-grid button {
  padding: 10px;
  border: 1px solid #e5e7eb;
  border-radius: 8px;
  background: #fff;
  color: #374151;
  font: 700 14px var(--mono);
  cursor: pointer;
}
.qb-calc-grid button.eq { background: #e5e7eb; color: #1f2937; border-color: #cbd5e1; }

/* Security Veil */
.qb-security-veil {
  position: absolute;
  inset: 0;
  z-index: 40;
  background-color: #f8f6f0;
  background-image: linear-gradient(#f8f6f0b8, #f8f6f0b8), url('/assets/codex-hex.svg');
  background-size: auto, 41.57px 72px;
  display: grid;
  place-items: center;
  padding: 24px;
}
.qb-security-card {
  max-width: 460px;
  background: #fff;
  border: 1.5px solid #d1d5db;
  border-radius: 20px;
  padding: 28px;
  text-align: center;
  box-shadow: 0 20px 50px rgba(0, 0, 0, .12);
}
.qb-security-card h3 { font: 400 30px var(--display); margin: 4px 0 10px; color: var(--ink); }
.qb-security-card p { font: 15px/1.55 var(--sans); color: var(--slate); margin: 0 0 18px; }

/* Footer Bar */
.qb-exam-foot {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
  padding: 11px 20px;
  background: #f9fafb;
  border-top: 1px solid #e5e7eb;
  flex: none;
}
.qb-foot-left, .qb-foot-right { display: flex; gap: 8px; align-items: center; }
.qb-foot-center { font: 500 11.5px var(--mono); color: #6b7280; }
.qb-foot-center kbd {
  border: 1px solid #d1d5db;
  border-bottom-width: 2px;
  border-radius: 4px;
  padding: 1px 5px;
  background: #ffffff;
}

/* Licence Modal & Toast */
.qb-modal {
  position: fixed;
  inset: 0;
  background-color: #f8f6f0;
  background-image: linear-gradient(#f8f6f0b8, #f8f6f0b8), url('/assets/codex-hex.svg');
  background-size: auto, 41.57px 72px;
  display: none;
  align-items: center;
  justify-content: center;
  z-index: 85;
  padding: 16px;
}
.qb-modal.on { display: flex; }
.qb-dlg { background: #fff; border-radius: 20px; max-width: 440px; width: 100%; padding: 24px; box-shadow: var(--shadow-lg); animation: qbin .16s ease-out; }
.qb-dlg h3 { font-family: var(--display); font-weight: 400; font-size: 30px; margin: 0 0 6px; color: var(--ink); }
.qb-dlg input { width: 100%; padding: 12px 14px; border: 1px solid var(--line-2); border-radius: 12px; font: 15px var(--sans); margin: 6px 0 10px; }
.qb-dlg .err { color: #B3261E; font: 13px var(--sans); min-height: 18px; }
.qb-small { font-family: var(--sans); font-size: 13.5px; color: var(--slate); }
.qb-toast {
  position: fixed;
  left: 50%;
  bottom: 22px;
  transform: translateX(-50%);
  background: var(--ink);
  color: #fff;
  padding: 10px 18px;
  border-radius: 999px;
  font: 600 13px var(--sans);
  opacity: 0;
  transition: opacity .2s;
  z-index: 95;
  pointer-events: none;
}
.qb-toast.on { opacity: 1; }

@media (max-width: 960px) {
  .qb-hero .in, .qb-prem, .qb-launch, .qb-workspace { grid-template-columns: 1fr; }
  .qb-workspace { overflow-y: auto; display: block; }
  .qb-pane { overflow: visible; }
  .qb-pane-stem { border-right: 0; border-bottom: 1px solid var(--line); }
  .qb-foot-center { display: none; }
}
@media (max-width: 640px) {
  .qb-player-modal { padding: 0; }
  .qb-player-shell { height: 100dvh; max-height: 100dvh; border-radius: 0; }
  .qb-connected-tiles { grid-template-columns: 1fr; }
  .qb-launch-preview { display: none; }
}
@media print {
  body > * { display: none !important; }
  body::before {
    content: "COPYRIGHT PROTECTED — THECODEXES.COM USMLE STEP 2 CK ONLINE QBANK — PRINTING & REDISTRIBUTION PROHIBITED";
    display: block;
    padding: 40px;
    font: 700 16px/1.6 Arial, sans-serif;
    color: #0b4a3d;
  }
}