/* ==========================================================================
   LÉXICO INFANTIL (10 AÑOS) - ESTILOS Y SISTEMA DE DISEÑO
   ========================================================================== */

:root {
  /* Paleta Modo Oscuro */
  --bg-main: #0c1017;
  --bg-surface: #151a24;
  --bg-card: #1c2230;
  --bg-card-hover: #232b3c;
  --border-subtle: #2d3748;
  --border-prominent: #4a5568;
  
  --text-primary: #f7fafc;
  --text-secondary: #cbd5e0;
  --text-muted: #8896aa;
  
  --accent-gold: #ffbe3b;
  --accent-gold-bg: rgba(255, 190, 59, 0.14);
  --accent-blue: #4da3ff;
  --accent-blue-bg: rgba(77, 163, 255, 0.12);
  --accent-purple: #b794f4;
  --accent-purple-bg: rgba(183, 148, 244, 0.12);
  
  --success: #38a169;
  --success-bg: rgba(56, 161, 105, 0.18);
  --success-border: #48bb78;
  
  --error: #e53e3e;
  --error-bg: rgba(229, 62, 62, 0.16);
  --error-border: #f56565;
  
  --card-shadow: 0 14px 40px rgba(0, 0, 0, 0.45);
  --card-radius: 20px;
  --transition: all 0.22s cubic-bezier(0.16, 1, 0.3, 1);
}

/* Modo Claro (Luminoso y Amigable) */
body.theme-light {
  --bg-main: #f5f8fc;
  --bg-surface: #ffffff;
  --bg-card: #ffffff;
  --bg-card-hover: #f7faff;
  --border-subtle: #e2e8f0;
  --border-prominent: #cbd5e0;
  
  --text-primary: #1a202c;
  --text-secondary: #4a5568;
  --text-muted: #718096;
  
  --accent-gold: #d69e2e;
  --accent-gold-bg: rgba(214, 158, 46, 0.12);
  --accent-blue: #3182ce;
  --accent-blue-bg: rgba(49, 130, 206, 0.1);
  --accent-purple: #805ad5;
  --accent-purple-bg: rgba(128, 90, 213, 0.1);
  
  --success: #2f855a;
  --success-bg: rgba(47, 133, 90, 0.12);
  --success-border: #38a169;
  
  --error: #c53030;
  --error-bg: rgba(197, 48, 48, 0.1);
  --error-border: #e53e3e;
  
  --card-shadow: 0 12px 35px rgba(50, 70, 100, 0.08);
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: 'Outfit', -apple-system, BlinkMacSystemFont, sans-serif;
  background-color: var(--bg-main);
  color: var(--text-primary);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  transition: background-color 0.3s ease, color 0.3s ease;
}

.app-container {
  width: 100%;
  max-width: 920px;
  margin: 0 auto;
  padding: 1.25rem 1.2rem 3rem;
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

/* ==========================================================================
   HEADER & DIFFICULTY LEVEL BADGE
   ========================================================================== */
.app-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 1rem;
  padding-bottom: 1.25rem;
  border-bottom: 1px solid var(--border-subtle);
  margin-bottom: 1.75rem;
}

.brand {
  display: flex;
  align-items: center;
  gap: 0.85rem;
}

.brand-icon {
  font-size: 2rem;
  background: var(--accent-gold-bg);
  width: 50px;
  height: 50px;
  border-radius: 14px;
  display: flex;
  align-items: center;
  justify-content: center;
  border: 1px solid rgba(255, 190, 59, 0.3);
}

.brand-title {
  font-family: 'Fredoka', 'Outfit', sans-serif;
  font-size: 1.75rem;
  letter-spacing: 0.05em;
  font-weight: 700;
  color: var(--accent-gold);
  line-height: 1.1;
}

.brand-sub {
  font-size: 0.8rem;
  color: var(--text-muted);
  font-weight: 500;
}

/* Level & Adaptive Card */
.level-progress-card {
  position: relative;
}

.level-badge {
  background: var(--bg-surface);
  border: 2px solid var(--accent-gold);
  padding: 0.4rem 0.95rem;
  border-radius: 30px;
  display: flex;
  align-items: center;
  gap: 0.65rem;
  cursor: pointer;
  transition: var(--transition);
  box-shadow: 0 4px 12px rgba(255, 190, 59, 0.15);
}

.level-badge:hover {
  background: var(--accent-gold-bg);
  transform: translateY(-1px);
}

.level-icon {
  font-size: 1.35rem;
}

.level-info {
  display: flex;
  flex-direction: column;
}

.level-tag {
  font-size: 0.82rem;
  font-weight: 700;
  color: var(--accent-gold);
  line-height: 1.2;
}

.level-sub {
  font-size: 0.72rem;
  color: var(--text-muted);
  font-weight: 500;
}

.level-dropdown-arrow {
  font-size: 0.85rem;
  color: var(--accent-gold);
}

.level-dropdown {
  position: absolute;
  top: calc(100% + 8px);
  left: 0;
  width: 270px;
  background: var(--bg-surface);
  border: 1px solid var(--border-prominent);
  border-radius: 14px;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.35);
  padding: 0.5rem;
  z-index: 100;
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
  animation: fadeIn 0.2s ease;
}

.dropdown-header {
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  color: var(--text-muted);
  padding: 0.4rem 0.6rem;
}

.dropdown-item {
  background: transparent;
  border: none;
  color: var(--text-primary);
  text-align: left;
  padding: 0.6rem 0.75rem;
  border-radius: 8px;
  font-size: 0.88rem;
  font-weight: 500;
  cursor: pointer;
  transition: var(--transition);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.dropdown-item:hover {
  background: var(--bg-card-hover);
  color: var(--accent-gold);
}

.dropdown-item.active {
  background: var(--accent-gold-bg);
  color: var(--accent-gold);
  font-weight: 700;
}

.dropdown-divider {
  height: 1px;
  background: var(--border-subtle);
  margin: 0.3rem 0;
}

/* Stats Pills */
.stats-bar {
  display: flex;
  align-items: center;
  gap: 0.6rem;
}

.stat-badge {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  padding: 0.35rem 0.75rem;
  border-radius: 25px;
  font-size: 0.85rem;
  font-weight: 500;
}

.stat-icon {
  font-size: 1rem;
}

.stat-value {
  font-weight: 700;
  color: var(--text-primary);
}

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

.streak-badge {
  border-color: rgba(255, 190, 59, 0.4);
  background: var(--accent-gold-bg);
}

.streak-badge .stat-value {
  color: var(--accent-gold);
}

/* Actions Header */
.header-actions {
  display: flex;
  align-items: center;
  gap: 0.6rem;
}

.btn-icon {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  color: var(--text-primary);
  padding: 0.5rem 0.85rem;
  border-radius: 12px;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 0.45rem;
  font-size: 0.85rem;
  font-weight: 600;
  transition: var(--transition);
}

.btn-icon:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-prominent);
}

.btn-secondary {
  background: var(--bg-surface);
  border: 2px solid var(--accent-gold);
  color: var(--accent-gold);
  padding: 0.5rem 0.95rem;
  border-radius: 12px;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 0.45rem;
  font-size: 0.85rem;
  font-weight: 700;
  transition: var(--transition);
}

.btn-secondary:hover {
  background: var(--accent-gold-bg);
  transform: translateY(-1px);
}

/* Toast for Level change */
.level-toast {
  background: var(--accent-gold);
  color: #1a202c;
  padding: 0.75rem 1.4rem;
  border-radius: 30px;
  display: flex;
  align-items: center;
  gap: 0.6rem;
  font-weight: 700;
  font-size: 0.95rem;
  box-shadow: 0 8px 25px rgba(255, 190, 59, 0.4);
  margin-bottom: 1.25rem;
  align-self: center;
  animation: slideUp 0.3s ease;
}

.toast-icon {
  font-size: 1.3rem;
}

/* ==========================================================================
   QUIZ CARD
   ========================================================================== */
.main-content {
  flex: 1;
  display: flex;
  flex-direction: column;
  position: relative;
}

.quiz-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--card-radius);
  padding: 2.25rem 2.2rem;
  box-shadow: var(--card-shadow);
  display: flex;
  flex-direction: column;
  gap: 1.75rem;
  transition: var(--transition);
}

.word-header-meta {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.word-tags {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  flex-wrap: wrap;
}

.level-pill {
  font-size: 0.78rem;
  font-weight: 700;
  color: var(--accent-gold);
  background: var(--accent-gold-bg);
  padding: 0.25rem 0.75rem;
  border-radius: 20px;
  border: 1px solid rgba(255, 190, 59, 0.3);
}

.category-pill {
  font-size: 0.78rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  font-weight: 600;
  color: var(--accent-blue);
  background: var(--accent-blue-bg);
  padding: 0.25rem 0.75rem;
  border-radius: 20px;
  border: 1px solid rgba(77, 163, 255, 0.3);
}

.word-actions {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.btn-tool {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  color: var(--text-secondary);
  padding: 0.4rem 0.85rem;
  border-radius: 10px;
  cursor: pointer;
  font-size: 0.82rem;
  font-weight: 600;
  display: flex;
  align-items: center;
  gap: 0.4rem;
  transition: var(--transition);
}

.btn-tool:hover {
  color: var(--text-primary);
  border-color: var(--border-prominent);
  background: var(--bg-card-hover);
}

/* 1. Word Hero */
.word-hero {
  text-align: center;
  padding: 1rem 0 0.5rem;
}

.word-title {
  font-family: 'Fredoka', 'Lora', serif;
  font-size: 3.5rem;
  font-weight: 700;
  color: var(--text-primary);
  letter-spacing: 0.01em;
  margin-bottom: 0.5rem;
  text-shadow: 0 2px 10px rgba(0, 0, 0, 0.2);
}

.word-instruction {
  font-size: 1.05rem;
  color: var(--text-muted);
  font-weight: 500;
}

/* 2. Options */
.options-container {
  display: flex;
  flex-direction: column;
  gap: 0.9rem;
}

.option-card {
  background: var(--bg-card);
  border: 2px solid var(--border-subtle);
  border-radius: 16px;
  padding: 1.15rem 1.35rem;
  cursor: pointer;
  display: flex;
  align-items: flex-start;
  gap: 1rem;
  text-align: left;
  transition: var(--transition);
  outline: none;
  width: 100%;
}

.option-card:hover:not(:disabled) {
  border-color: var(--accent-gold);
  background: var(--bg-card-hover);
  transform: translateY(-2px);
}

.option-card:focus-visible {
  border-color: var(--accent-blue);
  box-shadow: 0 0 0 3px var(--accent-blue-bg);
}

.option-badge {
  background: var(--bg-surface);
  border: 1.5px solid var(--border-prominent);
  color: var(--accent-gold);
  font-weight: 800;
  font-size: 0.95rem;
  width: 32px;
  height: 32px;
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  margin-top: 0.1rem;
}

.option-text {
  flex: 1;
  font-size: 1.1rem;
  color: var(--text-primary);
  line-height: 1.5;
  font-weight: 500;
}

.option-card.correct {
  background: var(--success-bg) !important;
  border-color: var(--success) !important;
}

.option-card.correct .option-badge {
  background: var(--success);
  color: #ffffff;
  border-color: var(--success);
}

.option-card.incorrect {
  background: var(--error-bg) !important;
  border-color: var(--error) !important;
  opacity: 0.85;
}

.option-card.incorrect .option-badge {
  background: var(--error);
  color: #ffffff;
  border-color: var(--error);
}

.option-card.faded {
  opacity: 0.45;
  cursor: not-allowed;
}

/* 3. Pistas (Hints) */
.hints-wrapper {
  background: var(--bg-card);
  border: 1.5px dashed var(--border-prominent);
  border-radius: 16px;
  padding: 1.25rem 1.4rem;
  display: flex;
  flex-direction: column;
  gap: 0.9rem;
}

.hints-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.hints-title {
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--text-secondary);
}

.hints-counter {
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--text-muted);
}

.hints-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
}

.btn-hint {
  background: var(--bg-surface);
  border: 1.5px solid var(--border-subtle);
  color: var(--text-primary);
  padding: 0.6rem 1.1rem;
  border-radius: 12px;
  cursor: pointer;
  font-size: 0.88rem;
  font-weight: 600;
  display: flex;
  align-items: center;
  gap: 0.5rem;
  transition: var(--transition);
}

.btn-hint:hover:not(:disabled) {
  border-color: var(--accent-gold);
  background: var(--accent-gold-bg);
}

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

.btn-hint.active {
  background: var(--accent-gold-bg);
  border-color: var(--accent-gold);
  color: var(--accent-gold);
}

.hint-box {
  background: var(--bg-surface);
  border-left: 4px solid var(--accent-gold);
  padding: 0.9rem 1.2rem;
  border-radius: 0 10px 10px 0;
  animation: fadeIn 0.3s ease;
}

.hint-label {
  font-size: 0.78rem;
  font-weight: 800;
  text-transform: uppercase;
  color: var(--accent-gold);
  margin-bottom: 0.35rem;
}

.hint-body {
  font-size: 1.02rem;
  color: var(--text-secondary);
  font-style: italic;
  line-height: 1.55;
}

/* 4. Feedback */
.feedback-panel {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: 16px;
  padding: 1.6rem;
  display: flex;
  flex-direction: column;
  gap: 1.35rem;
  animation: slideUp 0.3s ease;
}

.feedback-banner {
  padding: 0.9rem 1.25rem;
  border-radius: 12px;
  font-weight: 700;
  font-size: 1.15rem;
  display: flex;
  align-items: center;
  gap: 0.6rem;
}

.feedback-banner.correct {
  background: var(--success-bg);
  border: 1.5px solid var(--success-border);
  color: var(--success);
}

.feedback-banner.incorrect {
  background: var(--error-bg);
  border: 1.5px solid var(--error-border);
  color: var(--error);
}

.feedback-details {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.feedback-item {
  display: flex;
  flex-direction: column;
  gap: 0.3rem;
}

.feedback-heading {
  font-size: 0.82rem;
  font-weight: 800;
  text-transform: uppercase;
  color: var(--accent-gold);
}

.feedback-text {
  font-size: 1.05rem;
  color: var(--text-primary);
  line-height: 1.55;
}

.feedback-quote {
  font-family: 'Fredoka', 'Lora', serif;
  font-size: 1.12rem;
  font-style: italic;
  color: var(--text-primary);
  background: var(--bg-surface);
  padding: 0.85rem 1.15rem;
  border-left: 4px solid var(--accent-gold);
  border-radius: 0 10px 10px 0;
}

.feedback-actions {
  display: flex;
  justify-content: flex-end;
  padding-top: 0.5rem;
}

.btn-primary {
  background: var(--accent-gold);
  color: #12161f;
  border: none;
  padding: 0.8rem 1.8rem;
  border-radius: 14px;
  font-size: 1.05rem;
  font-weight: 800;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 0.65rem;
  transition: var(--transition);
  box-shadow: 0 4px 15px rgba(255, 190, 59, 0.35);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 22px rgba(255, 190, 59, 0.5);
}

.key-shortcut {
  font-size: 0.75rem;
  background: rgba(0, 0, 0, 0.15);
  padding: 0.2rem 0.5rem;
  border-radius: 6px;
}

/* ==========================================================================
   MODAL: BIBLIOTECA
   ========================================================================== */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.75);
  backdrop-filter: blur(5px);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 1000;
  padding: 1rem;
  animation: fadeIn 0.2s ease;
}

.modal-window {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: 20px;
  width: 100%;
  max-width: 700px;
  max-height: 85vh;
  display: flex;
  flex-direction: column;
  box-shadow: var(--card-shadow);
  overflow: hidden;
}

.modal-header {
  padding: 1.25rem 1.5rem;
  border-bottom: 1px solid var(--border-subtle);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.modal-title {
  font-family: 'Fredoka', 'Outfit', sans-serif;
  font-size: 1.4rem;
  font-weight: 700;
  color: var(--accent-gold);
}

.modal-sub {
  font-size: 0.8rem;
  color: var(--text-muted);
}

.btn-close {
  background: transparent;
  border: none;
  font-size: 2rem;
  color: var(--text-muted);
  cursor: pointer;
  line-height: 1;
}

.btn-close:hover {
  color: var(--text-primary);
}

.modal-tabs {
  display: flex;
  border-bottom: 1px solid var(--border-subtle);
  background: var(--bg-card);
  padding: 0 0.5rem;
  overflow-x: auto;
}

.modal-tab {
  background: transparent;
  border: none;
  color: var(--text-muted);
  padding: 0.75rem 0.95rem;
  font-size: 0.85rem;
  font-weight: 700;
  cursor: pointer;
  border-bottom: 2.5px solid transparent;
  white-space: nowrap;
  transition: var(--transition);
}

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

.modal-tab.active {
  color: var(--accent-gold);
  border-bottom-color: var(--accent-gold);
}

.search-bar-wrap {
  padding: 0.85rem 1.5rem;
  border-bottom: 1px solid var(--border-subtle);
}

.search-input {
  width: 100%;
  background: var(--bg-card);
  border: 1.5px solid var(--border-subtle);
  color: var(--text-primary);
  padding: 0.65rem 1rem;
  border-radius: 12px;
  font-size: 0.95rem;
  outline: none;
}

.search-input:focus {
  border-color: var(--accent-gold);
}

.modal-body {
  padding: 1.25rem 1.5rem;
  overflow-y: auto;
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 0.8rem;
}

.word-list-item {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: 14px;
  padding: 0.95rem 1.15rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  transition: var(--transition);
}

.word-list-item:hover {
  border-color: var(--border-prominent);
  background: var(--bg-card-hover);
}

.word-item-info {
  flex: 1;
}

.word-item-title {
  font-family: 'Fredoka', 'Lora', serif;
  font-size: 1.2rem;
  font-weight: 600;
  color: var(--text-primary);
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.word-item-badges {
  display: flex;
  align-items: center;
  gap: 0.4rem;
}

.word-item-lvl {
  font-size: 0.72rem;
  font-weight: 700;
  color: var(--accent-gold);
  background: var(--accent-gold-bg);
  padding: 0.15rem 0.5rem;
  border-radius: 12px;
}

.word-item-cat {
  font-size: 0.72rem;
  color: var(--accent-blue);
  background: var(--accent-blue-bg);
  padding: 0.15rem 0.5rem;
  border-radius: 12px;
}

.word-item-def {
  font-size: 0.92rem;
  color: var(--text-secondary);
  margin-top: 0.3rem;
  line-height: 1.45;
}

.btn-star {
  background: transparent;
  border: none;
  font-size: 1.35rem;
  cursor: pointer;
  padding: 0.3rem;
  color: var(--text-muted);
}

.btn-star.favorited {
  color: #ffbe3b;
}

/* Loader */
.loader-overlay {
  position: absolute;
  inset: 0;
  background: rgba(12, 16, 23, 0.88);
  backdrop-filter: blur(6px);
  border-radius: var(--card-radius);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 1.25rem;
  z-index: 50;
  animation: fadeIn 0.2s ease;
}

.spinner {
  width: 48px;
  height: 48px;
  border: 3.5px solid rgba(255, 190, 59, 0.2);
  border-top-color: var(--accent-gold);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

.loader-text {
  font-size: 1rem;
  color: var(--text-secondary);
  font-weight: 600;
}

/* Footer */
.app-footer {
  text-align: center;
  margin-top: auto;
  padding-top: 2rem;
  font-size: 0.82rem;
  color: var(--text-muted);
}

.app-footer a {
  color: var(--accent-gold);
  text-decoration: none;
}

.hidden {
  display: none !important;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

@keyframes slideUp {
  from { opacity: 0; transform: translateY(12px); }
  to { opacity: 1; transform: translateY(0); }
}

/* Responsive */
@media (max-width: 640px) {
  .app-header {
    flex-direction: column;
    align-items: stretch;
  }
  
  .level-progress-card {
    width: 100%;
  }

  .level-badge {
    width: 100%;
    justify-content: space-between;
  }

  .stats-bar {
    width: 100%;
    justify-content: space-between;
  }
  
  .header-actions {
    width: 100%;
    justify-content: space-between;
  }

  .word-title {
    font-size: 2.6rem;
  }
  
  .quiz-card {
    padding: 1.6rem 1.2rem;
  }
}