/* =========================================
   PAGE D'UNE LEÇON INTERACTIVE
   ========================================= */

.lesson-page {
  max-width: 1300px;
  margin: 0 auto;
  padding: 110px 2rem 4rem;
}

/* --- En-tête --- */
.lesson-top {
  display: flex;
  flex-direction: column;
  gap: 0.9rem;
  margin-bottom: 1.75rem;
}

.lesson-back {
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 0.9rem;
  width: max-content;
}

.lesson-back:hover {
  color: var(--accent);
}

.lesson-section {
  color: var(--accent);
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 1.5px;
  font-weight: 600;
}

.lesson-heading h1 {
  font-family: var(--font-heading);
  font-size: 2.2rem;
  color: var(--text-primary);
  margin: 0.25rem 0 0;
  font-weight: 600;
}

.lesson-progress {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.lesson-progress-track {
  flex: 1;
  height: 6px;
  background: var(--bg-tertiary);
  border-radius: 3px;
  overflow: hidden;
}

.lesson-progress-bar {
  width: 0;
  height: 100%;
  background: var(--accent);
  transition: width 0.35s ease;
}

.step-counter {
  color: var(--text-secondary);
  font-size: 0.85rem;
  font-variant-numeric: tabular-nums;
  white-space: nowrap;
}

.step-dots {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}

.step-dot {
  width: 14px;
  height: 14px;
  padding: 0;
  border-radius: 50%;
  border: 2px solid var(--border-strong);
  background: var(--bg-main);
  cursor: pointer;
  transition: all 0.15s ease;
}

.step-dot:hover {
  border-color: var(--accent);
}

.step-dot.done {
  background: var(--accent-dim);
  border-color: var(--accent-dim);
}

.step-dot.current {
  background: var(--accent);
  border-color: var(--accent);
  transform: scale(1.2);
}

.step-dot:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

/* --- Mise en page plateau + panneau --- */
.lesson-layout {
  display: grid;
  grid-template-columns: minmax(0, 620px) minmax(320px, 1fr);
  gap: 2.5rem;
  align-items: start;
}

.lesson-board-col {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.lesson-board-wrap {
  width: 100%;
}

#board {
  position: relative;
  width: 100%;
}

#board .board-b72b1 {
  border: 2px solid var(--border-subtle);
  border-radius: 4px;
  box-shadow: 0 15px 40px rgba(0, 0, 0, 0.45);
}

#lesson-overlay {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  z-index: 90;
}

.overlay-mark {
  fill: none;
  stroke: var(--accent);
  stroke-width: 1.1;
  opacity: 0.9;
}

/* Cases choisies dans les exercices "select" */
#board .lesson-picked {
  box-shadow: inset 0 0 0 4px var(--accent) !important;
  background-image: linear-gradient(rgba(200, 149, 106, 0.35), rgba(200, 149, 106, 0.35));
}

#board .lesson-good {
  box-shadow: inset 0 0 0 4px var(--win) !important;
  background-image: linear-gradient(rgba(123, 179, 148, 0.4), rgba(123, 179, 148, 0.4));
}

#board .lesson-bad {
  box-shadow: inset 0 0 0 4px var(--loss) !important;
  background-image: linear-gradient(rgba(209, 118, 109, 0.4), rgba(209, 118, 109, 0.4));
}

#board .lesson-missed {
  box-shadow: inset 0 0 0 4px var(--win) !important;
}

#board .highlight-last-move {
  box-shadow: inset 0 0 0 4px rgba(200, 149, 106, 0.5);
}

#board .selected-square {
  box-shadow: inset 0 0 0 4px var(--accent) !important;
}

.turn-info {
  padding: 10px 14px;
  background: var(--bg-secondary);
  border: 1px solid var(--border-subtle);
  border-left: 3px solid var(--accent);
  border-radius: 4px;
  color: var(--text-primary);
  font-size: 0.9rem;
}

/* --- Panneau explicatif --- */
.lesson-panel {
  background: var(--bg-secondary);
  border: 1px solid var(--border-subtle);
  border-radius: 6px;
  padding: 1.75rem;
  display: flex;
  flex-direction: column;
  gap: 1rem;
  position: sticky;
  top: 20px;
}

.step-type {
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 1.5px;
  color: var(--accent);
  font-weight: 600;
}

.step-title {
  font-family: var(--font-heading);
  font-size: 1.5rem;
  color: var(--text-primary);
  margin: 0;
  font-weight: 600;
}

.step-text {
  color: var(--text-secondary);
  line-height: 1.65;
  font-size: 1rem;
}

.step-text b {
  color: var(--text-primary);
}

.step-text ul,
.step-text ol {
  margin: 0.5rem 0;
  padding-left: 1.3rem;
}

.step-text li {
  margin: 0.3rem 0;
}

.step-text a {
  color: var(--accent);
}

/* Quiz */
.quiz-box {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.quiz-question {
  color: var(--text-primary);
  font-weight: 600;
  margin: 0 0 4px;
}

.quiz-choice {
  text-align: left;
  padding: 12px 14px;
  background: var(--bg-main);
  border: 1px solid var(--border-subtle);
  border-radius: 4px;
  color: var(--text-primary);
  font-family: var(--font-body);
  font-size: 0.95rem;
  line-height: 1.4;
  cursor: pointer;
  transition:
    border-color 0.15s ease,
    background-color 0.15s ease;
}

.quiz-choice:hover:not(:disabled) {
  border-color: var(--accent);
  background: var(--bg-tertiary);
}

.quiz-choice:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

.quiz-choice:disabled {
  cursor: default;
}

.quiz-choice.correct {
  border-color: var(--win);
  background: rgba(123, 179, 148, 0.15);
}

.quiz-choice.wrong {
  border-color: var(--loss);
  background: rgba(209, 118, 109, 0.12);
  color: var(--text-secondary);
}

/* Retour */
.feedback {
  padding: 12px 14px;
  border-radius: 4px;
  background: var(--bg-main);
  border: 1px solid var(--border-subtle);
  color: var(--text-secondary);
  line-height: 1.5;
  font-size: 0.95rem;
}

.feedback.good {
  border-color: var(--win);
  color: var(--text-primary);
}

.feedback.good b {
  color: var(--win);
}

.feedback.bad {
  border-color: var(--loss);
  color: var(--text-primary);
}

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

/* Boutons */
.step-tools,
.step-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.step-nav {
  justify-content: space-between;
  padding-top: 1rem;
  border-top: 1px solid var(--border-subtle);
}

.btn-lesson {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 11px 18px;
  border-radius: 4px;
  font-family: var(--font-body);
  font-size: 0.85rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 1px;
  text-decoration: none;
  cursor: pointer;
  transition: all 0.15s ease;
}

.btn-lesson[hidden] {
  display: none;
}

.btn-lesson.primary {
  background: var(--accent);
  border: 1px solid var(--accent);
  color: var(--on-accent);
}

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

.btn-lesson.ghost {
  background: transparent;
  border: 1px solid var(--border-strong);
  color: var(--text-primary);
}

.btn-lesson.ghost:hover:not(:disabled) {
  border-color: var(--text-secondary);
  background: var(--bg-tertiary);
}

.btn-lesson:disabled {
  opacity: 0.4;
  cursor: not-allowed;
}

.btn-lesson:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

.lesson-sources {
  font-size: 0.8rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

.lesson-sources a {
  color: var(--accent);
  text-decoration: none;
}

.lesson-sources a:hover {
  text-decoration: underline;
}

/* --- Fin de leçon --- */
.lesson-complete {
  position: fixed;
  inset: 0;
  background: rgba(5, 5, 5, 0.75);
  backdrop-filter: blur(4px);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 3000;
  padding: 16px;
}

.lesson-complete[hidden] {
  display: none;
}

.lesson-complete-card {
  background: var(--bg-secondary);
  border: 1px solid var(--border-subtle);
  border-top: 3px solid var(--accent);
  border-radius: 6px;
  padding: 2.5rem;
  max-width: 480px;
  width: 100%;
  text-align: center;
}

.lesson-complete-icon {
  font-size: 3rem;
  color: var(--accent);
  margin-bottom: 1rem;
}

.lesson-complete-card h2 {
  font-family: var(--font-heading);
  color: var(--text-primary);
  margin: 0 0 0.5rem;
}

.lesson-complete-card p {
  color: var(--text-secondary);
  margin-bottom: 1.75rem;
  line-height: 1.5;
}

.lesson-complete-actions {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.lesson-missing {
  text-align: center;
  padding: 4rem 0;
  color: var(--text-secondary);
}

.lesson-missing a {
  color: var(--accent);
}

/* --- Responsive --- */
@media (max-width: 980px) {
  .lesson-layout {
    grid-template-columns: 1fr;
  }

  .lesson-board-col {
    max-width: 600px;
    width: 100%;
    margin: 0 auto;
  }

  .lesson-panel {
    position: static;
  }
}

@media (max-width: 600px) {
  .lesson-page {
    padding: 90px 16px 3rem;
  }

  .lesson-heading h1 {
    font-size: 1.6rem;
  }

  .lesson-panel {
    padding: 1.25rem;
  }

  .step-nav .btn-lesson {
    flex: 1;
  }
}