:root {
  --bg: #171300;
  --top: #121120;
  --panel: #15191b;
  --panel-2: #1d2226;
  --text: #f6f2e9;
  --muted: #c9c1b5;
  --line: rgba(255,255,255,0.14);
  --blue: #0572b5;
  --blue-2: #0a95e6;
  --green: #176232;
  --red: #7b2c32;
  --pill: rgba(255,255,255,0.06);
  --top-controls-width: min(1500px, 88vw);
  --card-width: 88vw;
  --card-height: 420px;
  --greek-size: 96px;
  --definition-size: 38px;
  --top-menu-size: 17px;
  --prompt-size: 17px;
  --choice-button-size: 17px;
  --bottom-button-size: 17px;
  --audio-button-size: 15px;
  --greek-font: Georgia, 'Times New Roman', 'Noto Serif', serif;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  min-height: 100%;
  background: var(--bg);
  color: var(--text);
  font-family: Georgia, 'Times New Roman', serif;
  font-size: 16px;
}

button, select, input {
  font: inherit;
}

button {
  cursor: pointer;
}

button:disabled {
  cursor: not-allowed;
  opacity: .45;
}

.app {
  min-height: 100vh;
  background:
    radial-gradient(circle at top center, rgba(0, 114, 181, .08), transparent 35rem),
    var(--bg);
}

.app.theme-white-card {
  --bg: #211a04;
  --panel: #f8f6f0;
  --panel-2: #fffdf7;
  --text: #f6f2e9;
  --muted: #d8d2c6;
  --line: rgba(255,255,255,0.18);
}

.topbar {
  font-size: var(--top-menu-size);
  background: linear-gradient(180deg, #121120, #151324);
  border-bottom: 1px solid rgba(255,255,255,.08);
  padding: 12px clamp(18px, 4vw, 52px) 14px;
  z-index: 20;
}

.fixed-top .topbar {
  position: sticky;
  top: 0;
}

.brand-row {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 14px;
  margin-bottom: 16px;
  text-align: center;
}

.brand-mark {
  width: 42px;
  height: 28px;
  border-radius: 7px;
  display: grid;
  place-items: center;
  background: #086aa6;
  color: white;
  font-weight: 700;
  line-height: 1;
  box-shadow: inset 0 0 0 1px rgba(255,255,255,.2);
}

.brand-row h1 {
  margin: 0;
  font-size: clamp(26px, 3.6vw, 42px);
  letter-spacing: .02em;
}

.brand-row p {
  margin: 2px 0 0;
  font-style: italic;
  color: var(--muted);
  font-size: clamp(15px, 1.8vw, 20px);
}

.control-row, .status-row {
  width: var(--top-controls-width);
  max-width: none;
  margin-inline: auto;
  display: flex;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
}

.primary-controls {
  margin-top: 2px;
}

.secondary-controls {
  margin-top: 12px;
}

.status-row {
  margin-top: 16px;
}

select {
  appearance: auto;
  color: var(--text);
  background: #151a1d;
  border: 1px solid rgba(255,255,255,.25);
  border-radius: 8px;
  padding: 10px 16px;
  min-width: 230px;
}

.topbar select {
  font-size: var(--top-menu-size);
  padding: calc(var(--top-menu-size) * .55) calc(var(--top-menu-size) * .95);
  min-height: calc(var(--top-menu-size) * 2.55);
}

.btn, .chip, .audio-btn {
  border: 1px solid rgba(255,255,255,.18);
  border-radius: 9px;
  padding: 10px 18px;
  color: #fff;
  background: #1d2329;
  box-shadow: inset 0 1px 0 rgba(255,255,255,.06);
}

.topbar .btn,
.topbar .chip,
.topbar .check-label {
  font-size: var(--top-menu-size);
}

.topbar .btn,
.topbar .chip {
  padding: calc(var(--top-menu-size) * .55) calc(var(--top-menu-size) * 1.05);
  min-height: calc(var(--top-menu-size) * 2.45);
}

.btn:hover, .chip:hover, .audio-btn:hover {
  filter: brightness(1.12);
}

.btn-blue { background: var(--blue); }
.btn-green { background: var(--green); }
.btn-red { background: var(--red); }
.btn-muted { background: #22272d; }
.nav-btn { min-width: 64px; font-size: max(22px, calc(var(--bottom-button-size) + 6px)); }

.check-label {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  color: var(--text);
  white-space: nowrap;
}

.check-label.block {
  display: flex;
}

input[type="checkbox"] {
  width: 17px;
  height: 17px;
  accent-color: var(--blue);
}

.chip {
  padding: 8px 17px;
  border-radius: 999px;
  background: #151a1d;
}

.chip.active {
  background: var(--blue);
  border-color: rgba(255,255,255,.3);
}

.pill {
  border-radius: 999px;
  padding: 5px 16px;
  font-weight: 700;
  letter-spacing: .01em;
}

.pill-neutral { background: rgba(255,255,255,.06); }
.pill-blue { background: rgba(11, 108, 177, .28); color: #88cbff; }
.pill-green { background: rgba(23,98,50,.65); color: #bff6cc; }
.pill-red { background: rgba(123,44,50,.75); color: #ffd0d5; }

.progress-track {
  display: block;
  flex: 1 1 420px;
  height: 11px;
  background: rgba(255,255,255,.26);
  border: 1px solid rgba(255,255,255,.10);
  border-radius: 999px;
  overflow: hidden;
  min-width: 180px;
  box-shadow: inset 0 1px 2px rgba(0,0,0,.45);
}

.progress-fill {
  width: 0%;
  height: 100%;
  background: linear-gradient(90deg, var(--blue), var(--blue-2));
  transition: width .2s ease;
}

.study-shell {
  width: var(--card-width);
  max-width: 1500px;
  margin: 16px auto 0;
  padding-bottom: 24px;
}

.study-card {
  position: relative;
  min-height: var(--card-height);
  background: linear-gradient(180deg, var(--panel), #121618);
  border-radius: 14px;
  border: 1px solid rgba(255,255,255,.04);
  box-shadow: 0 14px 40px rgba(0,0,0,.22);
  outline: none;
  overflow: hidden;
}

.theme-white-card .study-card {
  color: #151515;
  background: linear-gradient(180deg, #ffffff, #f8f6f0);
  border: 1px solid rgba(0,0,0,.15);
}

.card-tools {
  position: absolute;
  top: 16px;
  right: 16px;
  display: flex;
  gap: 8px;
  z-index: 2;
}

.audio-btn {
  padding: calc(var(--audio-button-size) * .48) calc(var(--audio-button-size) * .78);
  min-height: calc(var(--audio-button-size) * 2.25);
  font-size: var(--audio-button-size);
  background: rgba(0,0,0,.24);
}

.theme-white-card .audio-btn {
  background: #e9edf0;
  color: #111;
}

.card-nav-btn {
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  z-index: 4;
  width: 60px;
  height: 68px;
  border-radius: 12px;
  border: 1px solid rgba(255,255,255,.18);
  background: #1d2329;
  color: #fff;
  font-size: max(24px, calc(var(--bottom-button-size) + 8px));
  line-height: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: inset 0 1px 0 rgba(255,255,255,.06), 0 8px 22px rgba(0,0,0,.18);
}

.card-nav-btn:hover {
  filter: brightness(1.12);
}

.card-nav-btn:disabled {
  opacity: .35;
  cursor: not-allowed;
}

.card-nav-left {
  left: 22px;
}

.card-nav-right {
  right: 22px;
}

.theme-white-card .card-nav-btn {
  background: #e9edf0;
  color: #111;
  border-color: rgba(0,0,0,.18);
}

.card-content {
  min-height: var(--card-height);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 64px 40px 42px;
}

.study-card.multiple-choice-mode .card-content {
  justify-content: center;
  min-height: var(--card-height);
  padding: clamp(34px, 4.5vh, 56px) 36px clamp(26px, 3.6vh, 40px);
}

.greek-word {
  font-family: var(--greek-font);
  font-size: var(--greek-size);
  line-height: 1.05;
  color: #d7d2cc;
  white-space: nowrap;
  overflow-wrap: normal;
  word-break: normal;
  max-width: 100%;
  display: inline-block;
  transition: font-size .15s ease;
}

.theme-white-card .greek-word {
  color: #111;
}

.type-label {
  position: absolute;
  top: 18px;
  left: 50%;
  transform: translateX(-50%);
  margin-top: 0;
  border-radius: 999px;
  background: rgba(0, 114, 181, .18);
  color: #55bfff;
  padding: 4px 12px;
  font-size: max(13px, calc(var(--prompt-size) - 3px));
  z-index: 3;
  pointer-events: none;
}

.theme-white-card .type-label {
  color: #005a8a;
  background: rgba(0, 114, 181, .12);
}

.reveal-hint {
  margin-top: 12px;
  min-height: 46px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--muted);
  font-size: var(--prompt-size);
  line-height: 1;
}

.study-card.flashcard-mode:not(.is-revealed) .card-content {
  position: static;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 64px 40px 42px;
}

.study-card.flashcard-mode:not(.is-revealed) .reveal-hint {
  position: absolute;
  left: 50%;
  top: var(--reveal-hint-top, 78%);
  transform: translate(-50%, -50%);
  margin-top: 0;
  min-height: auto;
  width: max-content;
  max-width: calc(100% - 80px);
  pointer-events: none;
  z-index: 2;
}

.reveal-hint.feedback-correct {
  color: #39ff88;
  font-size: max(30px, calc(var(--prompt-size) * 1.85));
  font-weight: 900;
  letter-spacing: .10em;
  text-transform: uppercase;
  text-shadow: 0 0 18px rgba(57, 255, 136, .65);
}

.reveal-hint.feedback-wrong {
  color: #ff4040;
  font-size: max(30px, calc(var(--prompt-size) * 1.85));
  font-weight: 900;
  letter-spacing: .10em;
  text-transform: uppercase;
  text-shadow: 0 0 18px rgba(255, 64, 64, .70);
}

.theme-white-card .reveal-hint,
.theme-white-card .meta-text,
.theme-white-card .principal-parts {
  color: #444;
}

.answer-area {
  margin-top: 18px;
  max-width: min(1100px, 92%);
}

.answer-area.mc-reserved {
  display: none;
}

.study-card.multiple-choice-mode .answer-area.mc-reserved {
  display: none;
}

.answer-area.answer-reserved-hidden {
  display: none;
}

.meaning-text {
  font-size: var(--definition-size);
  line-height: 1.22;
  color: #f5f1e9;
}

.theme-white-card .meaning-text {
  color: #151515;
}

.principal-parts {
  margin-top: 18px;
  font-size: max(18px, calc(var(--definition-size) * .58));
  line-height: 1.35;
  color: #d8d0c5;
}

.meta-text {
  margin-top: 18px;
  color: var(--muted);
  font-size: max(15px, calc(var(--prompt-size) - 1px));
}

.multiple-choice {
  width: min(920px, 94%);
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
  margin-top: 12px;
  flex: 0 0 auto;
}

.study-card.multiple-choice-mode .multiple-choice {
  margin-top: 10px;
}

.choice-btn {
  border: 1px solid rgba(255,255,255,.18);
  border-radius: 12px;
  background: #20272d;
  color: var(--text);
  font-size: var(--choice-button-size);
  font-weight: 700;
  padding: calc(var(--choice-button-size) * .72) calc(var(--choice-button-size) * 1.1);
  min-height: calc(var(--choice-button-size) * 3.25);
  line-height: 1.22;
  text-align: center;
  display: flex;
  align-items: center;
  justify-content: center;
}

.choice-btn.correct {
  background: rgba(25, 135, 70, .78);
  color: #d9ffe6;
  border-color: rgba(70, 255, 140, .58);
  box-shadow: inset 0 0 0 1px rgba(70, 255, 140, .20), 0 0 18px rgba(57, 255, 136, .15);
}

.choice-btn.wrong {
  background: rgba(145, 36, 43, .72);
  color: #ffd2d2;
  border-color: rgba(255, 80, 80, .58);
  box-shadow: inset 0 0 0 1px rgba(255, 80, 80, .18);
}

.choice-btn:disabled {
  opacity: 1;
  cursor: default;
}

.theme-white-card .choice-btn {
  background: #eef1f3;
  color: #151515;
  border-color: rgba(0,0,0,.18);
}

.theme-white-card .choice-btn.correct,
.theme-white-card .choice-btn.wrong {
  color: #fff;
}

.bottom-controls {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 14px;
  flex-wrap: wrap;
  margin-top: 18px;
}

.bottom-controls .btn {
  font-size: var(--bottom-button-size);
  font-weight: 700;
  padding: calc(var(--bottom-button-size) * .8) calc(var(--bottom-button-size) * 1.55);
  min-height: calc(var(--bottom-button-size) * 3.1);
  display: inline-flex;
  align-items: center;
  justify-content: center;
}

.settings-panel {
  position: fixed;
  font-size: 16px;
  top: 0;
  right: 0;
  width: min(520px, 96vw);
  height: 100vh;
  overflow-y: auto;
  background: #12171b;
  border-left: 1px solid rgba(255,255,255,.14);
  box-shadow: -20px 0 60px rgba(0,0,0,.45);
  z-index: 50;
  transform: translateX(104%);
  transition: transform .18s ease;
  padding: 22px;
}

.settings-panel.open {
  transform: translateX(0);
}

.settings-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 18px;
}

.settings-header h2 {
  margin: 0;
}

.settings-grid {
  display: grid;
  gap: 16px;
}

.settings-grid label {
  display: grid;
  gap: 8px;
  color: var(--text);
}

.settings-grid input[type="range"] {
  width: 100%;
}


.setting-group {
  display: grid;
  gap: 12px;
  padding: 0;
  border-radius: 10px;
}

.setting-group.setting-disabled {
  opacity: .45;
}

.setting-group.setting-disabled select,
.setting-group.setting-disabled input {
  cursor: not-allowed;
}

.setting-note {
  display: none;
  color: #c7c0b6;
  font-size: 14px;
  font-style: italic;
  margin-top: -4px;
}

.setting-group.setting-disabled .setting-note {
  display: block;
}

.settings-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 24px;
}

.empty-state {
  text-align: center;
  color: var(--muted);
}

.empty-state h2 {
  margin: 0 0 8px;
  color: var(--text);
}

.hidden { display: none !important; }




@media (max-height: 900px) {
  .study-shell {
    margin-top: 12px;
    padding-bottom: 18px;
  }

  .study-card.multiple-choice-mode .card-content {
    padding-top: 30px;
    padding-bottom: 28px;
  }

  .study-card.multiple-choice-mode .greek-word {
    line-height: .98;
  }

  .study-card.multiple-choice-mode .type-label {
    margin-top: 6px;
  }

  .study-card.multiple-choice-mode .reveal-hint {
    margin-top: 8px;
    min-height: 42px;
  }

  .study-card.multiple-choice-mode .multiple-choice {
    margin-top: 8px;
  }

  .choice-btn {
    min-height: 58px;
    padding-block: 12px;
  }

  .bottom-controls {
    margin-top: 14px;
  }
}

.mobile-header,
.mobile-backdrop {
  display: none;
}