:root {
  --bg: #0f1115;
  --bg-elev: #171a21;
  --bg-elev-2: #1f232c;
  --border: #2a2f3a;
  --text: #e8e9ed;
  --text-dim: #9aa0ac;
  --accent: #d9a441;
  --accent-2: #6fb0e0;
  --red: #e0556f;
  --black: #dfe2e8;
  --good: #59c37a;
  --bad: #e0556f;
  --radius: 14px;
  --shadow: 0 8px 30px rgba(0,0,0,.35);
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif;
  --font-serif: Georgia, "Times New Roman", serif;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font);
  min-height: 100%;
}

body {
  background-image:
    radial-gradient(circle at 15% 0%, rgba(217,164,65,.06), transparent 40%),
    radial-gradient(circle at 85% 20%, rgba(111,176,224,.06), transparent 40%);
}

a { color: var(--accent-2); }

/* Header / nav */
header.app-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(15,17,21,.85);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
}

.header-inner {
  max-width: 1100px;
  margin: 0 auto;
  padding: 14px 20px;
  display: flex;
  align-items: center;
  gap: 20px;
  flex-wrap: wrap;
}

nav.tabs {
  max-width: 100%;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: none;
}
nav.tabs::-webkit-scrollbar { display: none; }

.brand {
  font-family: var(--font-serif);
  font-size: 1.3rem;
  font-weight: 700;
  letter-spacing: .02em;
  color: var(--text);
  display: flex;
  align-items: center;
  gap: 8px;
  margin-right: auto;
}
.brand .mark { color: var(--accent); }

nav.tabs {
  display: flex;
  gap: 4px;
  background: var(--bg-elev);
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 4px;
}

nav.tabs button {
  border: none;
  background: transparent;
  color: var(--text-dim);
  padding: 8px 16px;
  border-radius: 999px;
  font-size: .92rem;
  cursor: pointer;
  transition: background .15s, color .15s;
  white-space: nowrap;
}
nav.tabs button:hover { color: var(--text); }
nav.tabs button.active {
  background: var(--accent);
  color: #1a1300;
  font-weight: 600;
}

main {
  max-width: 1100px;
  margin: 0 auto;
  padding: 28px 20px 80px;
}

.view { display: none; animation: fadein .25s ease; }
.view.active { display: block; }

@keyframes fadein { from { opacity: 0; transform: translateY(6px); } to { opacity: 1; transform: none; } }

h1, h2, h3 { font-family: var(--font-serif); font-weight: 700; letter-spacing: .01em; }
h1 { font-size: 1.8rem; margin: 0 0 6px; }
h2 { font-size: 1.3rem; margin: 0 0 10px; }
p.lead { color: var(--text-dim); margin: 0 0 24px; line-height: 1.5; max-width: 62ch; }

.card-panel {
  background: var(--bg-elev);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px;
  box-shadow: var(--shadow);
}

/* Playing card visual */
.pcard {
  width: 130px;
  height: 182px;
  border-radius: 12px;
  background: #fbfaf6;
  color: #111;
  box-shadow: 0 10px 30px rgba(0,0,0,.5), inset 0 0 0 1px rgba(0,0,0,.06);
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  padding: 10px 12px;
  font-family: var(--font-serif);
  position: relative;
  user-select: none;
}
.pcard.red { color: #c22; }
.pcard.black { color: #171717; }
.pcard .corner { font-size: 1.1rem; font-weight: 700; line-height: 1; }
.pcard .corner .r { display:block; }
.pcard .corner .s { display:block; font-size: 1rem; }
.pcard .corner.bottom { align-self: flex-end; transform: rotate(180deg); }
.pcard .center-symbol {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 3.6rem;
  opacity: .95;
}
.pcard.small { width: 74px; height: 104px; padding: 6px 8px; border-radius: 8px; }
.pcard.small .corner { font-size: .78rem; }
.pcard.small .corner .s { font-size: .72rem; }
.pcard.small .center-symbol { font-size: 1.9rem; }
.pcard.tiny { width: 52px; height: 74px; padding: 4px 6px; border-radius: 7px; }
.pcard.tiny .corner { font-size: .62rem; }
.pcard.tiny .center-symbol { font-size: 1.3rem; }
.pcard.ghost { background: var(--bg-elev-2); border: 1px dashed var(--border); box-shadow: none; }
.pcard.ghost .center-symbol { color: var(--text-dim); font-size: 1.4rem; }

/* Learn view */
.learn-stage {
  padding: 10px 0 6px;
}
#learn-active-panel {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 22px;
}
.learn-position {
  font-family: var(--font-serif);
  color: var(--accent);
  font-size: .95rem;
  letter-spacing: .08em;
  text-transform: uppercase;
}
.learn-flip {
  perspective: 1200px;
  width: 220px;
  height: 308px;
}
.learn-flip-inner {
  position: relative;
  width: 100%;
  height: 100%;
  transition: transform .5s cubic-bezier(.4,.2,.2,1);
  transform-style: preserve-3d;
}
.learn-flip.flipped .learn-flip-inner { transform: rotateY(180deg); }
.learn-face {
  position: absolute;
  inset: 0;
  backface-visibility: hidden;
  border-radius: 16px;
  display: flex;
  align-items: center;
  justify-content: center;
}
.learn-face.back { transform: rotateY(180deg); }
.learn-face .pcard { width: 100%; height: 100%; }
.mnemonic-box {
  background: var(--bg-elev-2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 18px 22px;
  max-width: 480px;
  text-align: center;
}
.mnemonic-box .peg-word { color: var(--accent); font-weight: 700; }
.mnemonic-box .sentence { font-size: 1.05rem; margin: 6px 0 4px; line-height: 1.5; }
.mnemonic-box .hint { color: var(--text-dim); font-size: .85rem; }

.learn-controls {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  justify-content: center;
  gap: 14px;
}
.btn {
  background: var(--bg-elev-2);
  border: 1px solid var(--border);
  color: var(--text);
  padding: 10px 18px;
  border-radius: 10px;
  cursor: pointer;
  font-size: .95rem;
  transition: transform .1s, background .15s, border-color .15s;
}
.btn:hover { background: #262b36; border-color: #3a4150; }
.btn:active { transform: scale(.97); }
.btn.primary { background: var(--accent); border-color: var(--accent); color: #1a1300; font-weight: 700; }
.btn.primary:hover { filter: brightness(1.08); }
.btn.ghost { background: transparent; }
.btn:disabled { opacity: .35; cursor: not-allowed; }

.progress-track {
  width: 100%;
  max-width: 480px;
  height: 8px;
  border-radius: 999px;
  background: var(--bg-elev-2);
  overflow: hidden;
  border: 1px solid var(--border);
}
.progress-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--accent-2), var(--accent));
  transition: width .3s ease;
}

.peg-info-toggle {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  background: var(--bg-elev);
  border: 1px solid var(--border);
  color: var(--text-dim);
  padding: 7px 14px 7px 8px;
  border-radius: 999px;
  font-size: .85rem;
  font-family: var(--font);
  cursor: pointer;
  margin-bottom: 14px;
  transition: border-color .15s, color .15s, background .15s;
}
.peg-info-toggle:hover { border-color: var(--accent); color: var(--text); background: var(--bg-elev-2); }
.peg-info-toggle[aria-expanded="true"] { border-color: var(--accent); color: var(--text); }
.peg-info-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 19px;
  height: 19px;
  border-radius: 50%;
  background: var(--accent);
  color: #1a1300;
  font-size: .72rem;
  font-weight: 800;
  font-style: italic;
  font-family: var(--font-serif);
  flex-shrink: 0;
}
.peg-info-chevron {
  font-size: .75rem;
  color: var(--text-dim);
  transition: transform .2s ease;
  line-height: 1;
}
.peg-info-toggle[aria-expanded="true"] .peg-info-chevron { transform: rotate(180deg); }

.peg-info-panel {
  display: none;
  margin-bottom: 20px;
}
.peg-info-panel.open {
  display: block;
  animation: fadein .25s ease;
}

.batch-size-row {
  display: flex;
  align-items: center;
  gap: 10px;
  justify-content: center;
  margin-bottom: 14px;
}
.batch-label { font-size: .8rem; color: var(--text-dim); }
.batch-toggle {
  display: flex;
  gap: 3px;
  background: var(--bg-elev);
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 3px;
}
.batch-toggle button {
  border: none;
  background: transparent;
  color: var(--text-dim);
  padding: 6px 14px;
  border-radius: 999px;
  font-size: .82rem;
  cursor: pointer;
}
.batch-toggle button.active { background: var(--accent); color: #1a1300; font-weight: 700; }

.custom-range-row {
  display: flex;
  align-items: center;
  gap: 8px;
  justify-content: center;
  flex-wrap: wrap;
  margin-bottom: 6px;
}
.range-input {
  background: var(--bg-elev-2);
  border: 1px solid var(--border);
  color: var(--text);
  padding: 6px 10px;
  border-radius: 8px;
  font-size: .85rem;
  width: 64px;
  text-align: center;
}
.range-input:focus { outline: 2px solid var(--accent); border-color: var(--accent); }
.range-dash { color: var(--text-dim); }
.range-error {
  color: var(--bad);
  font-size: .78rem;
  text-align: center;
  min-height: 1.2em;
  margin-bottom: 6px;
}

.decade-strip {
  display: flex;
  gap: 6px;
  flex-wrap: wrap;
  justify-content: center;
  margin-top: 4px;
  margin-bottom: 6px;
}
.decade-chip {
  font-size: .75rem;
  padding: 4px 10px;
  border-radius: 999px;
  border: 1px solid var(--border);
  color: var(--text-dim);
  cursor: pointer;
  background: var(--bg-elev-2);
  display: inline-flex;
  align-items: center;
  gap: 4px;
}
.decade-chip.active { color: #1a1300; background: var(--accent); border-color: var(--accent); }
.decade-chip.done:not(.active) { border-color: var(--good); color: var(--good); }
.decade-chip .done-mark { color: var(--good); }
.decade-chip.active .done-mark { color: #1a1300; }

.learn-position-sub {
  font-size: .78rem;
  color: var(--text-dim);
  margin-top: -14px;
}

.chunk-complete-badge {
  font-family: var(--font-serif);
  font-size: 1.4rem;
  color: var(--good);
  margin-bottom: 8px;
}
.chunk-complete-sub {
  color: var(--text-dim);
  margin: 0 0 20px;
}
#chunk-complete-panel {
  text-align: center;
  padding: 40px 20px;
  animation: fadein .25s ease;
}

/* Stack map */
.map-toolbar {
  display: flex;
  gap: 10px;
  margin-bottom: 18px;
  flex-wrap: wrap;
  align-items: center;
}
.map-toolbar input {
  background: var(--bg-elev-2);
  border: 1px solid var(--border);
  color: var(--text);
  padding: 8px 12px;
  border-radius: 8px;
  font-size: .9rem;
  min-width: 220px;
}
.map-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(90px, 1fr));
  gap: 10px;
}
.map-cell {
  background: var(--bg-elev);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 8px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 6px;
  cursor: default;
  transition: border-color .15s, transform .1s;
}
.map-cell:hover { border-color: var(--accent); transform: translateY(-2px); }
.map-cell .pos { font-size: .68rem; color: var(--text-dim); }
.map-cell .peg { font-size: .65rem; color: var(--accent-2); text-align: center; }
.map-cell.dim { opacity: .3; }

/* Practice / quiz */
.quiz-modes {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 14px;
  margin-bottom: 24px;
}
.mode-card {
  background: var(--bg-elev);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 18px;
  cursor: pointer;
  transition: border-color .15s, transform .1s;
}
.mode-card:hover { border-color: var(--accent); transform: translateY(-2px); }
.mode-card h3 { margin: 0 0 6px; font-size: 1.05rem; }
.mode-card p { margin: 0; color: var(--text-dim); font-size: .85rem; line-height: 1.4; }
.mode-card .tag {
  display: inline-block;
  font-size: .7rem;
  color: var(--accent);
  border: 1px solid var(--border);
  padding: 2px 8px;
  border-radius: 999px;
  margin-bottom: 8px;
}

.quiz-session { display: flex; flex-direction: column; align-items: center; gap: 20px; }
.quiz-hud {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 24px;
  justify-content: center;
  font-size: .85rem;
  color: var(--text-dim);
}
.quiz-hud b { color: var(--text); }
.quiz-question { text-align: center; }
.quiz-question .prompt { font-size: 1.1rem; margin-bottom: 14px; }
.answer-input-row { display: flex; gap: 10px; align-items: center; }
.answer-input-row input {
  background: var(--bg-elev-2);
  border: 1px solid var(--border);
  color: var(--text);
  padding: 12px 14px;
  border-radius: 10px;
  font-size: 1.1rem;
  width: 140px;
  text-align: center;
  text-transform: uppercase;
}
.answer-input-row input:focus { outline: 2px solid var(--accent); border-color: var(--accent); }

.mc-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 10px;
  max-width: 340px;
}
.mc-grid button {
  padding: 14px;
  font-size: 1rem;
}

.feedback-flash {
  font-weight: 700;
  font-size: .95rem;
  padding: 6px 14px;
  border-radius: 999px;
  min-height: 1.4em;
}
.feedback-flash.good { color: var(--good); }
.feedback-flash.bad { color: var(--bad); }

.suit-picker { display: flex; gap: 8px; }
.suit-picker button {
  font-size: 1.4rem;
  width: 56px;
  height: 56px;
  border-radius: 12px;
  background: var(--bg-elev-2);
  border: 1px solid var(--border);
  cursor: pointer;
}
.suit-picker button.red { color: var(--red); }
.suit-picker button.black { color: var(--black); }
.suit-picker button.selected { border-color: var(--accent); box-shadow: 0 0 0 2px var(--accent) inset; }

.rank-picker {
  display: grid;
  grid-template-columns: repeat(7, 1fr);
  gap: 8px;
  max-width: 420px;
}
.rank-picker button {
  padding: 10px 0;
  font-size: .95rem;
  border-radius: 8px;
  background: var(--bg-elev-2);
  border: 1px solid var(--border);
  cursor: pointer;
  color: var(--text);
}
.rank-picker button.selected { border-color: var(--accent); box-shadow: 0 0 0 2px var(--accent) inset; }

.results-box {
  text-align: center;
  padding: 30px;
}
.results-box .score { font-size: 2.6rem; font-family: var(--font-serif); color: var(--accent); }

/* Stats */
.stat-cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: 14px;
  margin-bottom: 26px;
}
.stat-card {
  background: var(--bg-elev);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 16px;
  text-align: center;
}
.stat-card .num { font-family: var(--font-serif); font-size: 1.8rem; color: var(--accent); }
.stat-card .lbl { color: var(--text-dim); font-size: .78rem; text-transform: uppercase; letter-spacing: .05em; }

.heatmap {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(38px, 1fr));
  gap: 5px;
}
.heat-cell {
  aspect-ratio: 1;
  border-radius: 6px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: .62rem;
  color: rgba(0,0,0,.65);
  font-weight: 700;
  cursor: default;
}

.weak-list { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 8px; }

footer.app-footer {
  text-align: center;
  color: var(--text-dim);
  font-size: .8rem;
  padding: 30px 20px 50px;
}

@media (max-width: 560px) {
  .learn-flip { width: 170px; height: 238px; }
  .pcard.small { width: 60px; height: 84px; }

  main { padding: 20px 14px 70px; }
  .header-inner { padding: 10px 14px; gap: 10px; }
  .brand { font-size: 1.1rem; }

  nav.tabs button { padding: 9px 13px; font-size: .85rem; min-height: 44px; }

  h1 { font-size: 1.5rem; }
  p.lead { font-size: .92rem; }

  .btn { min-height: 44px; padding: 10px 16px; }

  .range-input,
  #map-search,
  .answer-input-row input {
    font-size: 16px; /* prevent iOS auto-zoom on focus */
  }

  .rank-picker {
    grid-template-columns: repeat(5, 1fr);
    gap: 6px;
  }
  .rank-picker button { padding: 12px 0; min-height: 44px; }

  .suit-picker button { width: 48px; height: 48px; }

  .mc-grid { max-width: 100%; }
  .mc-grid button { min-height: 44px; }

  .map-grid { grid-template-columns: repeat(auto-fill, minmax(76px, 1fr)); }
}

.kbd {
  display: inline-block;
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 1px 6px;
  font-size: .78rem;
  color: var(--text-dim);
  font-family: monospace;
}