:root {
  --bg: #1a1d23;
  --surface: #242830;
  --border: #3a3f4d;
  --text: #e8eaef;
  --muted: #9aa3b2;
  --accent: #5b9fd4;
  --accent-hover: #7ab3e0;
  --ok: #4caf7a;
  --bad: #e57373;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.45;
}

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

.app {
  max-width: 960px;
  margin: 0 auto;
  padding: 1.25rem 1rem 2.5rem;
}

header {
  margin-bottom: 1.5rem;
}

header h1 {
  margin: 0 0 0.35rem;
  font-size: 1.35rem;
  font-weight: 600;
}

header p {
  margin: 0;
  font-size: 0.9rem;
  color: var(--muted);
}

.layout {
  display: grid;
  gap: 1.25rem;
}

@media (min-width: 720px) {
  .layout {
    grid-template-columns: 260px 1fr;
    align-items: start;
  }
}

.panel {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 1rem 1rem 1.1rem;
}

.panel h2 {
  margin: 0 0 0.75rem;
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--muted);
  font-weight: 600;
}

.cat-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-bottom: 0.75rem;
  align-items: stretch;
}

/* Start + Reset always visible; JS only toggles disabled state */
.quiz-toggle-slot {
  flex: 1 1 100%;
  min-width: min(100%, 18rem);
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  align-items: stretch;
}

.quiz-toggle-slot .start-btn {
  flex: 1 1 7.5rem;
  min-width: min(100%, 7rem);
  min-height: 2.35rem;
  padding: 0.5rem 0.75rem;
  font-size: 0.85rem;
  box-sizing: border-box;
  display: flex;
  align-items: center;
  justify-content: center;
}

.cat-actions .secondary-btn {
  width: auto;
}

button {
  font: inherit;
  cursor: pointer;
  border-radius: 8px;
  border: 1px solid var(--border);
  background: #2c313c;
  color: var(--text);
  padding: 0.45rem 0.75rem;
  font-size: 0.85rem;
}

button:hover:not(:disabled) {
  border-color: var(--accent);
  color: var(--accent-hover);
}

button:disabled {
  opacity: 0.45;
  cursor: not-allowed;
}

button.primary {
  background: var(--accent);
  border-color: var(--accent);
  color: #0d1117;
  font-weight: 600;
}

button.primary:hover:not(:disabled) {
  background: var(--accent-hover);
  border-color: var(--accent-hover);
}

.cat-form {
  margin: 0;
  padding: 0;
  border: none;
  min-width: 0;
}

.cat-list {
  max-height: min(52vh, 420px);
  overflow: auto;
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
  padding-right: 0.25rem;
}

.cat-list label {
  display: flex;
  align-items: flex-start;
  gap: 0.5rem;
  font-size: 0.82rem;
  cursor: pointer;
  color: var(--text);
}

.cat-list input {
  margin-top: 0.2rem;
}

.cat-list input:disabled + span,
.cat-list input:disabled {
  opacity: 0.55;
  cursor: not-allowed;
}

/* Hint only — never block clicks (validation is in startQuiz) */
button.start-btn.start-btn--needs-cats {
  opacity: 0.65;
}

.secondary-btn {
  width: 100%;
  background: transparent;
  border-style: dashed;
}

.actions .secondary-btn {
  width: auto;
}

.stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0.75rem;
  margin-bottom: 1rem;
}

.stat {
  background: #2c313c;
  border-radius: 8px;
  padding: 0.65rem 0.75rem;
  text-align: center;
  border: 1px solid var(--border);
}

.stat .label {
  font-size: 0.75rem;
  color: var(--muted);
  margin-bottom: 0.2rem;
}

.stat .value {
  font-size: 1.35rem;
  font-weight: 700;
}

.stat.ok .value {
  color: var(--ok);
}

.stat.bad .value {
  color: var(--bad);
}

.question-figure-wrap {
  margin: 0 0 0.85rem;
}

.question-figure-img {
  display: block;
  max-width: 100%;
  max-height: min(55vh, 420px);
  width: auto;
  height: auto;
  border-radius: 8px;
  border: 1px solid var(--border);
  object-fit: contain;
  background: #1e2128;
}

.question-image-hint {
  margin: 0 0 0.75rem;
  font-size: 0.82rem;
  color: var(--muted);
}

.question-card {
  margin-bottom: 1rem;
}

.question-meta {
  font-size: 0.8rem;
  color: var(--muted);
  margin-bottom: 0.5rem;
}

.question-text {
  font-size: 1.05rem;
  margin: 0 0 1rem;
}

.answers {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.answer {
  display: flex;
  align-items: flex-start;
  gap: 0.6rem;
  padding: 0.65rem 0.75rem;
  border-radius: 8px;
  border: 1px solid var(--border);
  background: #2c313c;
  cursor: pointer;
}

.answer:hover {
  border-color: #5a6270;
}

.answer input {
  margin-top: 0.2rem;
}

.answer.correct-pick {
  border-color: var(--ok);
  background: rgba(76, 175, 122, 0.12);
}

.answer.wrong-pick {
  border-color: var(--bad);
  background: rgba(229, 115, 115, 0.1);
}

.answer.reveal-correct {
  border-color: var(--ok);
  box-shadow: 0 0 0 1px var(--ok);
}

.feedback {
  min-height: 1.5rem;
  font-size: 0.9rem;
  margin: 0.75rem 0 0;
}

.feedback.ok {
  color: var(--ok);
}

.feedback.bad {
  color: var(--bad);
}

.actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
  margin-top: 1rem;
  align-items: center;
}

.redo-banner {
  margin: 0.75rem 0 0;
  font-size: 0.9rem;
  color: var(--accent);
}

#btn-exit-redo {
  border-color: var(--accent);
  color: var(--accent);
}

.load-overlay {
  position: fixed;
  inset: 0;
  z-index: 1000;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--bg);
  color: var(--text);
}

body.app-ready .load-overlay {
  display: none;
}

.load-overlay--error .load-overlay__text {
  color: var(--bad);
  max-width: 28rem;
  text-align: center;
  line-height: 1.4;
}

.load-overlay__text {
  margin: 0;
  font-size: 1rem;
  color: var(--muted);
}

.loading,
.error {
  padding: 2rem;
  text-align: center;
  color: var(--muted);
}

.error {
  color: var(--bad);
}

.answers {
  display: grid;
  grid-template-columns: 1fr;
  gap: 0.75rem;
}

@media (min-width: 900px) {
  .answers {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

.answer {
  display: flex;
  align-items: flex-start;
  gap: 0.75rem;
  padding: 0.75rem;
  border-radius: 10px;
  border: 1px solid var(--border);
  background: #2c313c;
  cursor: pointer;
}

.answer-content {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  width: 100%;
}

.answer-title {
  font-size: 1rem;
}

.answer-option-image {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  border-radius: 8px;
  border: 1px solid var(--border);
  background: white;
}

.answer-text {
  font-size: 0.95rem;
  line-height: 1.4;
}