/* ─── Opening Lab — Laboratorio de Aperturas (Fase 3) ─── */

/* ─ Screen layout ─ */
#opening-screen {
  flex-direction: column;
  padding: 0;
  min-height: 100vh;
  background: var(--bg-primary);
}

/* ─ Header ─ */
.opening-header {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 1rem 1.25rem 0.5rem;
  border-bottom: 1px solid var(--border);
  background: var(--bg-secondary);
}

.opening-back-btn {
  background: none;
  border: 1px solid var(--border);
  color: var(--text-secondary);
  padding: 0.35rem 0.75rem;
  border-radius: 6px;
  cursor: pointer;
  font-size: 0.85rem;
  transition: border-color 0.15s, color 0.15s;
}
.opening-back-btn:hover {
  border-color: var(--cyan);
  color: var(--cyan);
}

.opening-title-group {
  flex: 1;
  min-width: 0;
}

.opening-lab-title {
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--text-primary);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.opening-lab-eco-badge {
  display: inline-block;
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 0.05em;
  padding: 0.15rem 0.5rem;
  border-radius: 4px;
  background: var(--bg-tertiary);
  color: var(--cyan);
  border: 1px solid var(--cyan);
  margin-left: 0.4rem;
}

/* ─ Layer tabs ─ */
.opening-tabs {
  display: flex;
  gap: 0;
  padding: 0 1.25rem;
  background: var(--bg-secondary);
  border-bottom: 1px solid var(--border);
  overflow-x: auto;
  scrollbar-width: none;
}
.opening-tabs::-webkit-scrollbar { display: none; }

.opening-tab {
  flex: 1;
  min-width: 90px;
  padding: 0.65rem 0.5rem 0.5rem;
  background: none;
  border: none;
  border-bottom: 3px solid transparent;
  color: var(--text-secondary);
  font-size: 0.8rem;
  font-weight: 500;
  cursor: pointer;
  transition: color 0.15s, border-color 0.15s;
  text-align: center;
  white-space: nowrap;
  position: relative;
}

.opening-tab:hover { color: var(--text-primary); }

.opening-tab.active {
  color: var(--cyan);
  border-bottom-color: var(--cyan);
}

.opening-tab.tab-complete {
  color: var(--success, #4caf50);
}
.opening-tab.tab-complete.active {
  border-bottom-color: var(--success, #4caf50);
}

.opening-tab-label {
  display: block;
  font-size: 0.75rem;
}

.opening-tab-sublabel {
  display: block;
  font-size: 0.65rem;
  opacity: 0.7;
  margin-top: 0.1rem;
}

.opening-tab-progress {
  position: absolute;
  bottom: 0; left: 0;
  height: 3px;
  background: var(--cyan);
  opacity: 0.4;
  transition: width 0.4s ease;
}

/* ─ Content area ─ */
.opening-content {
  flex: 1;
  overflow-y: auto;
  padding: 1.25rem;
  max-width: 900px;
  margin: 0 auto;
  width: 100%;
}

/* ─ Layer 1: Gran Idea ─ */
.opening-gran-idea {
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

.opening-lema {
  font-size: 1.1rem;
  font-style: italic;
  color: var(--cyan);
  padding: 1rem 1.25rem;
  border-left: 3px solid var(--cyan);
  background: rgba(0, 229, 255, 0.06);
  border-radius: 0 8px 8px 0;
  line-height: 1.5;
}

.opening-content-block {
  color: var(--text-primary);
  line-height: 1.7;
}
.opening-content-block p { margin-bottom: 0.75rem; }
.opening-content-block p:last-child { margin-bottom: 0; }

.opening-section-title {
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-secondary);
  margin-bottom: 0.4rem;
}

.opening-tipo-jugador,
.opening-mensaje {
  display: flex;
  align-items: flex-start;
  gap: 0.75rem;
  padding: 0.875rem 1rem;
  background: var(--bg-secondary);
  border-radius: 8px;
  border: 1px solid var(--border);
  font-size: 0.92rem;
  line-height: 1.6;
}

.opening-icon {
  font-size: 1.1rem;
  flex-shrink: 0;
  margin-top: 0.05rem;
}

.opening-keywords {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.opening-keyword-chip {
  display: inline-block;
  padding: 0.25rem 0.65rem;
  border-radius: 20px;
  background: rgba(106, 27, 154, 0.25);
  border: 1px solid var(--orchid);
  color: var(--text-primary);
  font-size: 0.78rem;
}

.opening-nivel-note {
  display: flex;
  align-items: flex-start;
  gap: 0.75rem;
  padding: 0.75rem 1rem;
  background: rgba(194, 24, 91, 0.08);
  border-radius: 8px;
  border: 1px solid rgba(194, 24, 91, 0.3);
  font-size: 0.88rem;
  line-height: 1.5;
}

.opening-nivel-badge {
  flex-shrink: 0;
  padding: 0.2rem 0.55rem;
  background: var(--fuchsia);
  color: white;
  border-radius: 4px;
  font-size: 0.72rem;
  font-weight: 600;
}

.opening-continue-btn {
  align-self: flex-end;
  margin-top: 0.5rem;
}

/* ─ Layer 2: Planes ─ */
.opening-planes { display: flex; flex-direction: column; gap: 1rem; }

.opening-planes-header {
  display: flex;
  align-items: center;
  gap: 1rem;
  flex-wrap: wrap;
}

.opening-planes-count {
  font-size: 0.8rem;
  color: var(--text-secondary);
  font-weight: 500;
}

.opening-orden-text {
  font-size: 0.88rem;
  color: var(--text-secondary);
  font-style: italic;
  line-height: 1.5;
  margin: 0;
}

.opening-plan-card {
  border: 1px solid var(--border);
  border-radius: 10px;
  background: var(--bg-secondary);
  overflow: hidden;
  transition: border-color 0.2s;
}
.opening-plan-card:hover { border-color: var(--cyan); }

.opening-plan-header {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 1rem;
  cursor: pointer;
  user-select: none;
}

.opening-plan-number {
  font-size: 1.4rem;
  font-weight: 700;
  flex-shrink: 0;
  width: 1.8rem;
  text-align: center;
  line-height: 1;
}

.opening-plan-title-group { flex: 1; }
.opening-plan-nombre { font-weight: 600; font-size: 0.95rem; color: var(--text-primary); }
.opening-plan-eslogan { font-size: 0.8rem; color: var(--text-secondary); margin-top: 0.15rem; }

.opening-plan-toggle {
  font-size: 0.8rem;
  color: var(--text-secondary);
  transition: transform 0.2s;
}
.opening-plan-card.expanded .opening-plan-toggle { transform: rotate(180deg); }

.opening-plan-body {
  display: none;
  padding: 0 1rem 1rem;
  flex-direction: column;
  gap: 0.65rem;
}
.opening-plan-card.expanded .opening-plan-body { display: flex; }

.opening-plan-desc {
  font-size: 0.9rem;
  line-height: 1.65;
  color: var(--text-primary);
  margin: 0;
}

.opening-plan-row {
  display: flex;
  gap: 0.75rem;
  font-size: 0.875rem;
  line-height: 1.5;
}

.opening-plan-label {
  flex-shrink: 0;
  width: 95px;
  font-weight: 600;
  color: var(--text-secondary);
  font-size: 0.78rem;
  padding-top: 0.1rem;
}

.opening-plan-piezas { display: flex; flex-wrap: wrap; gap: 0.35rem; }

.opening-plan-advertencia {
  padding: 0.5rem 0.75rem;
  background: rgba(255, 87, 34, 0.1);
  border-left: 3px solid var(--orange);
  border-radius: 0 6px 6px 0;
  font-size: 0.85rem;
  color: var(--text-primary);
}

/* ─ GM Section ─ */
.opening-gm-section {
  margin-top: 1.5rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--border);
}

.opening-gm-header {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: 1rem;
}

.opening-gm-icon {
  font-size: 1.5rem;
  color: var(--orchid);
}

.opening-gm-title {
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-primary);
}

.opening-gm-style-badge {
  padding: 0.25rem 0.5rem;
  border-radius: 4px;
  font-size: 0.72rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}
.opening-gm-style-badge[data-style="Posicional"] { background: rgba(0, 229, 255, 0.15); color: var(--cyan); }
.opening-gm-style-badge[data-style="Tactico"] { background: rgba(189, 147, 249, 0.15); color: var(--orchid); }
.opening-gm-style-badge[data-style="Agresivo"] { background: rgba(255, 121, 198, 0.15); color: var(--fuchsia); }
.opening-gm-style-badge[data-style="Defensivo"] { background: rgba(255, 179, 71, 0.15); color: var(--amber); }

.opening-gm-refs {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  margin-bottom: 1rem;
  font-size: 0.85rem;
}

.opening-gm-refs-label {
  color: var(--text-secondary);
}

.opening-gm-chip {
  padding: 0.2rem 0.5rem;
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: 4px;
  font-size: 0.8rem;
  color: var(--text-primary);
}

.opening-gm-plans-list {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.opening-gm-plan-card {
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--bg-secondary);
  overflow: hidden;
  transition: border-color 0.15s;
}
.opening-gm-plan-card:hover { border-color: var(--orchid); }

.opening-gm-plan-header {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.75rem 1rem;
  cursor: pointer;
  user-select: none;
}

.opening-gm-plan-gm {
  font-weight: 600;
  font-size: 0.9rem;
}

.opening-gm-plan-style {
  font-size: 0.72rem;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.opening-gm-plan-toggle {
  margin-left: auto;
  color: var(--text-secondary);
  font-size: 0.75rem;
  transition: transform 0.2s;
}

.opening-gm-plan-card.expanded .opening-gm-plan-toggle { transform: rotate(180deg); }

.opening-gm-plan-body {
  display: none;
  flex-direction: column;
  gap: 0.75rem;
  padding: 0 1rem 1rem;
  border-top: 1px solid var(--border);
}

.opening-gm-plan-card.expanded .opening-gm-plan-body { display: flex; }

.opening-gm-plan-name {
  font-weight: 600;
  color: var(--text-primary);
  font-size: 0.95rem;
}

.opening-gm-plan-eslogan {
  font-style: italic;
  color: var(--text-secondary);
  font-size: 0.85rem;
}

.opening-gm-plan-desc {
  font-size: 0.88rem;
  line-height: 1.6;
  color: var(--text-primary);
  margin: 0;
}

.opening-gm-plan-row {
  display: flex;
  gap: 0.75rem;
  font-size: 0.85rem;
  line-height: 1.5;
}

.opening-gm-plan-label {
  flex-shrink: 0;
  width: 120px;
  font-weight: 600;
  color: var(--text-secondary);
  font-size: 0.78rem;
  padding-top: 0.1rem;
}

.opening-gm-plan-errors {
  font-size: 0.85rem;
}

.opening-gm-plan-errors ul {
  margin: 0.25rem 0 0 1.25rem;
  padding: 0;
}

.opening-gm-plan-errors li {
  margin-bottom: 0.25rem;
  color: var(--text-primary);
}

.opening-gm-plan-game {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.5rem;
  background: var(--bg-primary);
  border-radius: 6px;
}

.opening-gm-plan-game-label {
  font-size: 0.8rem;
  color: var(--text-secondary);
}

.opening-gm-view-game {
  padding: 0.4rem 0.75rem;
  background: rgba(189, 147, 249, 0.15);
  border: 1px solid var(--orchid);
  border-radius: 6px;
  color: var(--orchid);
  font-size: 0.8rem;
  font-weight: 500;
  cursor: pointer;
  transition: background 0.15s;
}
.opening-gm-view-game:hover {
  background: rgba(189, 147, 249, 0.25);
}

/* ─ GM Game Modal ─ */
.opening-gm-modal {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(0, 0, 0, 0.8);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 1000;
  padding: 1rem;
}

.opening-gm-modal-content {
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: 12px;
  width: 100%;
  max-width: 800px;
  max-height: 90vh;
  overflow: hidden;
}

.opening-gm-modal-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem;
  border-bottom: 1px solid var(--border);
}

.opening-gm-modal-header h3 {
  margin: 0;
  font-size: 1.1rem;
  color: var(--text-primary);
}

.opening-gm-modal-close {
  background: none;
  border: none;
  color: var(--text-secondary);
  font-size: 1.5rem;
  cursor: pointer;
  padding: 0;
  line-height: 1;
}
.opening-gm-modal-close:hover { color: var(--text-primary); }

.opening-gm-modal-body {
  display: grid;
  grid-template-columns: 1fr 300px;
  gap: 1rem;
  padding: 1rem;
  max-height: calc(90vh - 60px);
  overflow-y: auto;
}

@media (max-width: 680px) {
  .opening-gm-modal-body {
    grid-template-columns: 1fr;
  }
}

.opening-gm-game-board {
  aspect-ratio: 1;
  max-height: 400px;
}

.opening-gm-game-info {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.opening-gm-game-moves {
  display: flex;
  flex-wrap: wrap;
  gap: 0.25rem;
  font-size: 0.8rem;
  max-height: 300px;
  overflow-y: auto;
}

.opening-gm-move {
  padding: 0.2rem 0.4rem;
  border-radius: 4px;
  cursor: pointer;
  transition: background 0.1s;
}
.opening-gm-move:hover { background: var(--bg-secondary); }
.opening-gm-move.active {
  background: rgba(189, 147, 249, 0.2);
  color: var(--orchid);
  font-weight: 600;
}

.opening-gm-game-controls {
  display: flex;
  gap: 0.5rem;
}

.opening-gm-game-controls button {
  flex: 1;
  padding: 0.5rem;
  background: var(--bg-primary);
  border: 1px solid var(--border);
  border-radius: 6px;
  color: var(--text-primary);
  font-size: 1rem;
  cursor: pointer;
  transition: border-color 0.15s;
}
.opening-gm-game-controls button:hover {
  border-color: var(--orchid);
}

.opening-conflictos {
  padding: 1rem;
  background: var(--bg-secondary);
  border-radius: 8px;
  border: 1px solid var(--border);
  font-size: 0.88rem;
  line-height: 1.6;
}

/* ─ Layer 3: Líneas ─ */
.opening-lines-layout {
  display: grid;
  grid-template-columns: 220px 1fr;
  gap: 1.25rem;
  height: 100%;
}

@media (max-width: 680px) {
  .opening-lines-layout {
    grid-template-columns: 1fr;
  }
}

.opening-lines-sidebar { display: flex; flex-direction: column; gap: 0.75rem; }

.opening-lines-title {
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--text-secondary);
}

.opening-lines-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
}

.opening-line-item {
  display: flex;
  flex-direction: column;
  gap: 0.2rem;
  padding: 0.65rem 0.75rem;
  border-radius: 8px;
  border: 1px solid var(--border);
  cursor: pointer;
  transition: border-color 0.15s, background 0.15s;
}
.opening-line-item:hover { border-color: var(--cyan); background: var(--bg-secondary); }
.opening-line-item.active {
  border-color: var(--cyan);
  background: rgba(0, 229, 255, 0.07);
}

.opening-line-nombre { font-size: 0.85rem; font-weight: 500; color: var(--text-primary); }
.opening-line-dif { font-size: 0.72rem; color: var(--text-secondary); }
.opening-line-dif--basica { color: var(--cyan); }
.opening-line-dif--intermedia { color: var(--orchid); }
.opening-line-dif--avanzada { color: var(--fuchsia); }

.opening-lines-review {
  padding: 0.75rem;
  background: var(--bg-secondary);
  border-radius: 8px;
  border: 1px solid var(--border);
  font-size: 0.82rem;
  color: var(--text-secondary);
}
.opening-review-title {
  font-size: 0.72rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  margin-bottom: 0.35rem;
}
.opening-review-badge {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 1.4rem;
  height: 1.4rem;
  background: var(--fuchsia);
  color: white;
  border-radius: 50%;
  font-size: 0.75rem;
  font-weight: 700;
  margin-right: 0.3rem;
}

/* ─ Practice board area ─ */
.opening-board-area { display: flex; flex-direction: column; gap: 0.75rem; }

.opening-chessboard {
  width: 100%;
  max-width: 360px;
  margin: 0 auto;
}

.opening-tree-container {
  max-height: 120px;
  overflow-y: auto;
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 0.5rem 0.75rem;
}

.opening-move-tree {
  display: flex;
  flex-wrap: wrap;
  gap: 0.2rem 0;
  font-size: 0.88rem;
}

.tree-pair {
  display: flex;
  align-items: center;
  gap: 0.15rem;
}

.tree-num {
  color: var(--text-secondary);
  font-size: 0.78rem;
  padding: 0 0.25rem;
  user-select: none;
}

.tree-move {
  background: none;
  border: none;
  color: var(--text-primary);
  padding: 0.2rem 0.4rem;
  border-radius: 4px;
  cursor: pointer;
  font-size: 0.88rem;
  transition: background 0.12s;
}
.tree-move:hover { background: var(--bg-tertiary); }
.tree-move.current {
  background: var(--cyan);
  color: #000;
  font-weight: 600;
}
.tree-move--placeholder { width: 2.5rem; display: inline-block; }

/* ─ Practice controls ─ */
.opening-controls {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  flex-wrap: wrap;
}

.ctrl-btn {
  width: 2.25rem;
  height: 2.25rem;
  display: flex;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--border);
  border-radius: 6px;
  background: var(--bg-secondary);
  color: var(--text-primary);
  cursor: pointer;
  font-size: 0.8rem;
  transition: border-color 0.15s;
}
.ctrl-btn:hover { border-color: var(--cyan); color: var(--cyan); }

.opening-practice-status {
  font-size: 0.85rem;
  padding: 0.5rem 0.75rem;
  border-radius: 6px;
  background: rgba(0, 229, 255, 0.08);
  border: 1px solid rgba(0, 229, 255, 0.25);
  color: var(--cyan);
}
.opening-practice-status--deviation {
  background: rgba(233, 30, 99, 0.1);
  border-color: rgba(233, 30, 99, 0.4);
  color: var(--magenta);
}
.opening-practice-status--active { color: var(--cyan); }

/* ─ Layer 4: Desviaciones ─ */
.opening-deviation {
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

.opening-deviation-header {
  display: flex;
  align-items: flex-start;
  gap: 1rem;
  padding: 1rem;
  background: rgba(233, 30, 99, 0.06);
  border: 1px solid rgba(233, 30, 99, 0.25);
  border-radius: 10px;
}

.opening-deviation-icon {
  font-size: 1.5rem;
  flex-shrink: 0;
}

.opening-deviation-title {
  font-size: 0.78rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-secondary);
  margin-bottom: 0.25rem;
}

.opening-deviation-move {
  font-size: 1rem;
  color: var(--text-primary);
}

.opening-deviation-tipo {
  display: inline-block;
  font-size: 0.72rem;
  padding: 0.15rem 0.5rem;
  border-radius: 4px;
  margin-left: 0.5rem;
  font-weight: 600;
}
.opening-deviation-tipo--error_tactico    { background: rgba(255, 87, 34, 0.2); color: var(--orange); }
.opening-deviation-tipo--error_posicional { background: rgba(233, 30, 99, 0.2); color: var(--magenta); }
.opening-deviation-tipo--idea_alternativa { background: rgba(0, 229, 255, 0.15); color: var(--cyan); }
.opening-deviation-tipo--trampa           { background: rgba(255, 235, 59, 0.15); color: var(--yellow); }
.opening-deviation-tipo--novedad          { background: rgba(106, 27, 154, 0.2); color: var(--orchid); }

.opening-deviation-question {
  font-size: 1.05rem;
  line-height: 1.7;
  color: var(--text-primary);
  padding: 1rem 1.25rem;
  border-left: 3px solid var(--magenta);
  background: rgba(233, 30, 99, 0.04);
  border-radius: 0 8px 8px 0;
}

.opening-deviation-hint {
  display: flex;
  gap: 0.75rem;
  align-items: flex-start;
  font-size: 0.88rem;
  color: var(--text-secondary);
  padding: 0.65rem 0.875rem;
  background: var(--bg-secondary);
  border-radius: 8px;
  border: 1px solid var(--border);
}
.opening-deviation-hint-label {
  font-weight: 600;
  color: var(--yellow);
  flex-shrink: 0;
}

.opening-deviation-answer {
  display: flex;
  flex-direction: column;
  gap: 0.65rem;
}

.opening-deviation-textarea {
  width: 100%;
  min-height: 90px;
  padding: 0.75rem;
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: 8px;
  color: var(--text-primary);
  font-size: 0.9rem;
  line-height: 1.5;
  resize: vertical;
  transition: border-color 0.15s;
  font-family: inherit;
}
.opening-deviation-textarea:focus { outline: none; border-color: var(--cyan); }
.opening-deviation-textarea.input-error { border-color: var(--fuchsia); }

.opening-deviation-feedback {
  padding: 1rem;
  background: rgba(0, 229, 255, 0.06);
  border: 1px solid rgba(0, 229, 255, 0.25);
  border-radius: 10px;
}
.opening-deviation-feedback-inner { display: flex; flex-direction: column; gap: 0.65rem; }
.opening-deviation-followup {
  font-style: italic;
  color: var(--text-secondary);
  font-size: 0.9rem;
  padding: 0.5rem 0.875rem;
  border-left: 2px solid var(--cyan);
}

.opening-deviation-empty {
  text-align: center;
  color: var(--text-secondary);
  padding: 2rem 1rem;
  font-size: 0.92rem;
  line-height: 1.65;
}

/* ─ Skeletons ─ */
.skeleton-line {
  height: 1rem;
  background: linear-gradient(90deg, var(--bg-secondary) 25%, var(--bg-tertiary) 50%, var(--bg-secondary) 75%);
  background-size: 200% 100%;
  animation: skeleton-shimmer 1.5s infinite;
  border-radius: 4px;
  margin-bottom: 0.75rem;
}
@keyframes skeleton-shimmer {
  0%   { background-position: 200% 0; }
  100% { background-position: -200% 0; }
}

/* ─ Error state ─ */
.opening-error {
  text-align: center;
  padding: 2rem;
  color: var(--text-secondary);
}

/* ─── Responsive: Multiplataforma ─── */

/* Tablet (max-width: 768px) */
@media (max-width: 768px) {
  .opening-header {
    padding: 0.875rem 1rem 0.5rem;
    gap: 0.5rem;
  }

  .opening-tabs {
    padding: 0 1rem;
  }

  .opening-tab {
    min-width: 70px;
    padding: 0.55rem 0.4rem 0.45rem;
    font-size: 0.75rem;
  }

  .opening-tab-label {
    font-size: 0.72rem;
  }

  .opening-tab-num {
    display: none;
  }

  /* Capa 1: Gran Idea */
  .opening-gran-idea {
    padding: 1rem;
  }

  .opening-lema {
    font-size: 1.1rem;
    line-height: 1.5;
  }

  .opening-content-block {
    font-size: 0.9rem;
    line-height: 1.6;
  }

  .opening-keywords {
    gap: 0.4rem;
  }

  .opening-keyword-chip {
    font-size: 0.7rem;
    padding: 0.2rem 0.5rem;
  }

  /* Capa 2: Planes */
  .opening-planes {
    padding: 1rem;
  }

  .opening-plan-card {
    margin-bottom: 0.75rem;
  }

  .opening-plan-nombre {
    font-size: 0.95rem;
  }

  .opening-plan-desc {
    font-size: 0.88rem;
  }

  /* Capa 3: Líneas */
  .opening-lines-layout {
    grid-template-columns: 1fr;
    gap: 1rem;
    padding: 1rem;
  }

  .opening-lines-sidebar {
    order: 2;
  }

  .opening-board-area {
    order: 1;
  }

  .opening-chessboard {
    max-width: 320px;
  }

  .opening-controls {
    justify-content: center;
  }

  /* Capa 4: Desviaciones */
  .opening-deviation-header {
    padding: 0.875rem;
    gap: 0.75rem;
  }

  .opening-deviation-question {
    font-size: 0.95rem;
    padding: 0.875rem 1rem;
  }

  .opening-deviation-textarea {
    min-height: 80px;
  }

  /* GM Reference cards */
  .gm-reference-card {
    padding: 0.875rem;
    gap: 0.5rem;
  }

  .gm-reference-name {
    font-size: 0.9rem;
  }

  .gm-reference-stats {
    font-size: 0.78rem;
  }

  .gm-game-example {
    font-size: 0.82rem;
    padding: 0.6rem;
  }

  /* Botones */
  .btn-primary {
    padding: 0.65rem 1.25rem;
    font-size: 0.88rem;
  }

  .btn-ghost {
    padding: 0.5rem 1rem;
    font-size: 0.85rem;
  }
}

/* Mobile (max-width: 480px) */
@media (max-width: 480px) {
  .opening-header {
    padding: 0.75rem 0.875rem 0.4rem;
    flex-wrap: wrap;
  }

  .opening-back-btn {
    font-size: 0.8rem;
    padding: 0.3rem 0.6rem;
  }

  .opening-lab-title {
    font-size: 1rem;
    width: 100%;
    order: 3;
  }

  .opening-lab-eco-badge {
    font-size: 0.65rem;
    padding: 0.1rem 0.4rem;
    margin-left: 0;
    order: 2;
  }

  .opening-tabs {
    padding: 0 0.5rem;
    gap: 0;
  }

  .opening-tab {
    min-width: 60px;
    padding: 0.5rem 0.25rem 0.4rem;
    font-size: 0.7rem;
  }

  .opening-tab-label {
    display: none;
  }

  .opening-tab-num {
    display: block;
    font-size: 0.75rem;
  }

  .opening-tab .opening-tab-progress {
    height: 2px;
  }

  /* Capa 1: Gran Idea */
  .opening-gran-idea {
    padding: 0.875rem;
  }

  .opening-lema {
    font-size: 1rem;
    line-height: 1.4;
    margin-bottom: 0.75rem;
  }

  .opening-section-title {
    font-size: 0.7rem;
    margin-bottom: 0.5rem;
  }

  .opening-content-block {
    font-size: 0.85rem;
    line-height: 1.55;
  }

  .opening-tipo-jugador,
  .opening-mensaje {
    padding: 0.6rem;
    font-size: 0.85rem;
  }

  .opening-keywords {
    gap: 0.35rem;
  }

  .opening-keyword-chip {
    font-size: 0.65rem;
    padding: 0.15rem 0.4rem;
  }

  .opening-continue-btn {
    width: 100%;
    margin-top: 1rem;
    padding: 0.75rem;
    font-size: 0.9rem;
  }

  /* Capa 2: Planes */
  .opening-planes {
    padding: 0.875rem;
  }

  .opening-planes-header {
    margin-bottom: 0.75rem;
  }

  .opening-planes-count {
    font-size: 0.82rem;
  }

  .opening-orden-text {
    font-size: 0.82rem;
  }

  .opening-plan-card {
    margin-bottom: 0.5rem;
    border-radius: 8px;
  }

  .opening-plan-header {
    padding: 0.6rem 0.75rem;
  }

  .opening-plan-number {
    width: 1.5rem;
    height: 1.5rem;
    font-size: 0.7rem;
  }

  .opening-plan-nombre {
    font-size: 0.88rem;
  }

  .opening-plan-eslogan {
    font-size: 0.78rem;
  }

  .opening-plan-body {
    padding: 0.6rem 0.75rem;
  }

  .opening-plan-desc {
    font-size: 0.85rem;
    line-height: 1.5;
  }

  .opening-plan-row {
    font-size: 0.82rem;
  }

  .opening-plan-label {
    font-size: 0.7rem;
  }

  .opening-plan-piezas {
    gap: 0.3rem;
  }

  .opening-plan-advertencia {
    font-size: 0.82rem;
    padding: 0.5rem 0.65rem;
  }

  /* GM Reference cards */
  .gm-reference-section {
    margin-top: 1rem;
    padding-top: 1rem;
    border-top: 1px solid var(--border);
  }

  .gm-reference-title {
    font-size: 0.72rem;
    margin-bottom: 0.5rem;
  }

  .gm-reference-card {
    padding: 0.75rem;
    border-radius: 8px;
    margin-bottom: 0.5rem;
  }

  .gm-reference-avatar {
    width: 2rem;
    height: 2rem;
    font-size: 0.75rem;
  }

  .gm-reference-name {
    font-size: 0.85rem;
  }

  .gm-reference-style {
    font-size: 0.7rem;
  }

  .gm-reference-stats {
    font-size: 0.72rem;
  }

  .gm-game-example {
    padding: 0.5rem;
    font-size: 0.78rem;
  }

  .gm-game-label {
    font-size: 0.65rem;
  }

  .gm-game-name {
    font-size: 0.78rem;
  }

  .gm-game-details {
    font-size: 0.72rem;
  }

  .gm-view-game-btn {
    font-size: 0.72rem;
    padding: 0.3rem 0.6rem;
  }

  /* Capa 3: Líneas */
  .opening-lines-layout {
    grid-template-columns: 1fr;
    gap: 0.75rem;
    padding: 0.875rem;
  }

  .opening-lines-sidebar {
    order: 2;
    padding: 0;
  }

  .opening-lines-title {
    font-size: 0.68rem;
  }

  .opening-line-item {
    padding: 0.5rem 0.65rem;
    gap: 0.15rem;
  }

  .opening-line-nombre {
    font-size: 0.82rem;
  }

  .opening-line-dif {
    font-size: 0.68rem;
  }

  .opening-board-area {
    order: 1;
  }

  .opening-chessboard {
    max-width: 280px;
  }

  .opening-tree-container {
    max-height: 100px;
    padding: 0.4rem 0.6rem;
  }

  .opening-move-tree {
    font-size: 0.82rem;
  }

  .tree-num {
    font-size: 0.72rem;
    padding: 0 0.2rem;
  }

  .tree-move {
    font-size: 0.82rem;
    padding: 0.15rem 0.3rem;
  }

  .opening-controls {
    gap: 0.3rem;
    flex-wrap: wrap;
    justify-content: center;
  }

  .ctrl-btn {
    width: 2rem;
    height: 2rem;
    font-size: 0.75rem;
  }

  .btn-accent {
    padding: 0.45rem 0.9rem;
    font-size: 0.82rem;
  }

  .btn-ghost {
    padding: 0.4rem 0.8rem;
    font-size: 0.8rem;
  }

  .opening-practice-status {
    font-size: 0.82rem;
    padding: 0.4rem 0.65rem;
    text-align: center;
  }

  /* Capa 4: Desviaciones */
  .opening-deviation-header {
    padding: 0.75rem;
    gap: 0.6rem;
  }

  .opening-deviation-icon {
    font-size: 1.25rem;
  }

  .opening-deviation-title {
    font-size: 0.72rem;
  }

  .opening-deviation-move {
    font-size: 0.9rem;
  }

  .opening-deviation-tipo {
    font-size: 0.65rem;
    padding: 0.1rem 0.4rem;
    margin-left: 0.35rem;
  }

  .opening-deviation-question {
    font-size: 0.88rem;
    padding: 0.75rem 0.875rem;
    line-height: 1.6;
  }

  .opening-deviation-hint {
    font-size: 0.82rem;
    padding: 0.5rem 0.65rem;
    gap: 0.5rem;
  }

  .opening-deviation-textarea {
    min-height: 70px;
    font-size: 0.85rem;
    padding: 0.65rem;
  }

  .opening-deviation-feedback {
    padding: 0.875rem;
  }

  .opening-deviation-feedback-inner p {
    font-size: 0.85rem;
  }

  .opening-deviation-followup {
    font-size: 0.82rem;
    padding: 0.4rem 0.65rem;
  }

  /* Botones principales */
  .btn-primary {
    padding: 0.6rem 1rem;
    font-size: 0.85rem;
    width: 100%;
    text-align: center;
  }

  .opening-continue-btn {
    margin-top: 0.75rem;
    padding: 0.65rem 1rem;
    font-size: 0.85rem;
  }
}

/* Desktop grande (min-width: 1024px) */
@media (min-width: 1024px) {
  #opening-screen {
    max-width: 900px;
    margin: 0 auto;
  }

  .opening-header {
    padding: 1.25rem 1.5rem 0.6rem;
  }

  .opening-tabs {
    padding: 0 1.5rem;
  }

  .opening-tab {
    min-width: 120px;
    padding: 0.75rem 0.75rem 0.6rem;
  }

  .opening-tab-label {
    font-size: 0.85rem;
  }

  /* Capa 1 */
  .opening-gran-idea {
    padding: 1.5rem;
    max-width: 700px;
  }

  .opening-lema {
    font-size: 1.3rem;
    line-height: 1.6;
  }

  .opening-content-block {
    font-size: 1rem;
    line-height: 1.7;
  }

  /* Capa 2 */
  .opening-planes {
    padding: 1.5rem;
    max-width: 800px;
  }

  .opening-plan-nombre {
    font-size: 1.1rem;
  }

  .opening-plan-desc {
    font-size: 0.95rem;
  }

  /* Capa 3 */
  .opening-lines-layout {
    grid-template-columns: 250px 1fr;
    gap: 1.5rem;
    padding: 1.5rem;
    max-width: 900px;
  }

  .opening-chessboard {
    max-width: 400px;
  }

  /* Capa 4 */
  .opening-deviation-question {
    font-size: 1.1rem;
    padding: 1.25rem 1.5rem;
  }
}

/* Touch devices */
@media (pointer: coarse) {
  .opening-tab {
    min-height: 44px;
  }

  .opening-plan-header {
    min-height: 44px;
  }

  .opening-line-item {
    min-height: 44px;
  }

  .ctrl-btn {
    min-width: 44px;
    min-height: 44px;
  }

  .btn-primary,
  .btn-ghost,
  .opening-continue-btn {
    min-height: 44px;
  }
}

/* Print styles (for exporting notes) */
@media print {
  .opening-header,
  .opening-tabs,
  .opening-controls,
  .opening-continue-btn,
  .opening-deviation-answer {
    display: none;
  }

  .opening-gran-idea,
  .opening-planes,
  .opening-deviation {
    break-inside: avoid;
  }

  .opening-plan-card {
    break-inside: avoid;
    page-break-inside: avoid;
  }
}