/* Google Fonts for optimal readability */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700&family=Outfit:wght@500;600;700;800&display=swap');

:root {
  --bg-color: #f8fafc;
  --panel-bg: #ffffff;
  --border-color: #cbd5e1;
  --border-focus: #4f46e5;
  --text-primary: #0f172a;
  --text-secondary: #334155;
  --text-muted: #64748b;
  --accent-indigo: #4f46e5;
  --accent-hover: #4338ca;
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
  --shadow-hover: 0 10px 15px -3px rgba(79, 70, 229, 0.1);

  --font-title: 'Outfit', sans-serif;
  --font-body: 'Inter', sans-serif;
  --font-japanese: 'Helvetica Neue', Arial, 'Hiragino Kaku Gothic ProN', 'Hiragino Sans', Meiryo, sans-serif;

  /* WaniKani Level Colors */
  --pleasant-bg: #e0f2fe;
  --pleasant-border: #0284c7;
  --pleasant-text: #0369a1;

  --painful-bg: #f3e8ff;
  --painful-border: #7c3aed;
  --painful-text: #6d28d9;

  --death-bg: #ffe4e6;
  --death-border: #e11d48;
  --death-text: #be123c;

  --hell-bg: #ffedd5;
  --hell-border: #ea580c;
  --hell-text: #c2410c;

  --paradise-bg: #fce7f3;
  --paradise-border: #db2777;
  --paradise-text: #be185d;

  --reality-bg: #fef9c3;
  --reality-border: #ca8a04;
  --reality-text: #a16207;

  --unranked-bg: #f1f5f9;
  --unranked-border: #64748b;
  --unranked-text: #475569;
}

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

body {
  background-color: var(--bg-color);
  color: var(--text-primary);
  font-family: var(--font-body);
  line-height: 1.6;
  padding: 2.5rem 1.5rem;
  min-height: 100vh;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
}

/* Header */
header {
  margin-bottom: 2.5rem;
  border-bottom: 2px solid #e2e8f0;
  padding-bottom: 2rem;
  display: flex;
  justify-content: space-between;
  align-items: flex-end;
  flex-wrap: wrap;
  gap: 1.5rem;
}

.header-content {
  flex: 1;
  min-width: 300px;
}

.title-badge {
  color: var(--accent-indigo);
  font-family: var(--font-title);
  font-weight: 700;
  font-size: 0.85rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  margin-bottom: 0.5rem;
}

header h1 {
  font-family: var(--font-title);
  font-weight: 800;
  font-size: 2.5rem;
  color: var(--text-primary);
  margin-bottom: 0.75rem;
  letter-spacing: -0.02em;
}

header p {
  color: var(--text-secondary);
  font-size: 1.1rem;
  max-width: 700px;
}

.stats-bar {
  display: flex;
  gap: 1.25rem;
}

.stat-item {
  background: var(--panel-bg);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 0.75rem 1.25rem;
  min-width: 120px;
  text-align: center;
  box-shadow: var(--shadow-sm);
}

.stat-value {
  font-family: var(--font-title);
  font-weight: 700;
  font-size: 1.6rem;
  color: var(--text-primary);
  line-height: 1.2;
}

.stat-label {
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--text-muted);
  text-transform: uppercase;
}

/* Control Panel */
.control-panel {
  background: var(--panel-bg);
  border: 1px solid var(--border-color);
  border-radius: 12px;
  padding: 1.5rem;
  margin-bottom: 2.5rem;
  box-shadow: var(--shadow-sm);
}

.controls-row {
  display: flex;
  gap: 1.25rem;
  margin-bottom: 1.25rem;
  flex-wrap: wrap;
}

.search-box-wrapper {
  position: relative;
  flex: 1;
  min-width: 250px;
}

.search-icon {
  position: absolute;
  left: 1rem;
  top: 50%;
  transform: translateY(-50%);
  color: var(--text-muted);
  pointer-events: none;
}

.search-box {
  width: 100%;
  background: #ffffff;
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 0.75rem 1rem 0.75rem 2.75rem;
  color: var(--text-primary);
  font-family: var(--font-body);
  font-size: 0.95rem;
  transition: all 0.2s ease;
}

.search-box:focus {
  outline: none;
  border-color: var(--border-focus);
  box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.15);
}

/* Tab buttons */
.tabs-group {
  display: flex;
  background: #f1f5f9;
  padding: 0.25rem;
  border-radius: 8px;
  border: 1px solid #e2e8f0;
}

.tab-btn {
  background: transparent;
  border: none;
  padding: 0.6rem 1.25rem;
  border-radius: 6px;
  font-family: var(--font-body);
  font-weight: 600;
  font-size: 0.9rem;
  color: var(--text-secondary);
  cursor: pointer;
  transition: all 0.2s ease;
}

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

.tab-btn.active {
  background: #ffffff;
  color: var(--accent-indigo);
  box-shadow: var(--shadow-sm);
}

/* Legend Section */
.legend-section {
  padding-top: 1.25rem;
  border-top: 1px solid #e2e8f0;
}

.legend-header {
  font-size: 0.8rem;
  font-weight: 700;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 0.75rem;
}

.legend-container {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.legend-item {
  background: #ffffff;
  border: 1px solid var(--border-color);
  padding: 0.4rem 0.8rem;
  border-radius: 6px;
  font-family: var(--font-body);
  font-size: 0.8rem;
  font-weight: 500;
  color: var(--text-secondary);
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 0.5rem;
  transition: all 0.2s ease;
}

.legend-item .color-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  display: inline-block;
}

/* Dynamic Classes for Legend Groups */
.legend-item.group-1-10 .color-dot { background-color: var(--pleasant-border); }
.legend-item.group-11-20 .color-dot { background-color: var(--painful-border); }
.legend-item.group-21-30 .color-dot { background-color: var(--death-border); }
.legend-item.group-31-40 .color-dot { background-color: var(--hell-border); }
.legend-item.group-41-50 .color-dot { background-color: var(--paradise-border); }
.legend-item.group-51-60 .color-dot { background-color: var(--reality-border); }
.legend-item.group-unranked .color-dot { background-color: var(--unranked-border); }

/* Legend Item States & Selection */
.legend-item.active {
  font-weight: 700;
  color: var(--text-primary);
  transform: translateY(-1px);
}
.legend-item.group-1-10.active { background: var(--pleasant-bg); border-color: var(--pleasant-border); }
.legend-item.group-11-20.active { background: var(--painful-bg); border-color: var(--painful-border); }
.legend-item.group-21-30.active { background: var(--death-bg); border-color: var(--death-border); }
.legend-item.group-31-40.active { background: var(--hell-bg); border-color: var(--hell-border); }
.legend-item.group-41-50.active { background: var(--paradise-bg); border-color: var(--paradise-border); }
.legend-item.group-51-60.active { background: var(--reality-bg); border-color: var(--reality-border); }
.legend-item.group-unranked.active { background: var(--unranked-bg); border-color: var(--unranked-border); }

.legend-item:hover {
  background: #f8fafc;
  border-color: #94a3b8;
}

/* Kanji Grid */
.kanji-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(130px, 1fr));
  gap: 1rem;
}

/* Kanji Card Component */
.kanji-card {
  text-decoration: none;
  background: var(--panel-bg);
  border: 1px solid var(--border-color);
  border-radius: 10px;
  padding: 0.85rem;
  text-align: center;
  transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
  display: flex;
  flex-direction: column;
  align-items: center;
  box-shadow: var(--shadow-sm);
  position: relative;
  overflow: hidden;
}

.kanji-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-hover);
  z-index: 10;
}

/* Color Coding Themes */
.kanji-card.lvl-1-10 { background-color: var(--pleasant-bg); border-color: var(--pleasant-border); color: var(--pleasant-text); }
.kanji-card.lvl-11-20 { background-color: var(--painful-bg); border-color: var(--painful-border); color: var(--painful-text); }
.kanji-card.lvl-21-30 { background-color: var(--death-bg); border-color: var(--death-border); color: var(--death-text); }
.kanji-card.lvl-31-40 { background-color: var(--hell-bg); border-color: var(--hell-border); color: var(--hell-text); }
.kanji-card.lvl-41-50 { background-color: var(--paradise-bg); border-color: var(--paradise-border); color: var(--paradise-text); }
.kanji-card.lvl-51-60 { background-color: var(--reality-bg); border-color: var(--reality-border); color: var(--reality-text); }
.kanji-card.lvl-unranked { background-color: var(--unranked-bg); border-color: var(--unranked-border); color: var(--unranked-text); }

/* Large Kanji Char */
.kanji-char {
  font-family: var(--font-japanese);
  font-size: 2.75rem;
  font-weight: 700;
  line-height: 1.1;
  margin-bottom: 0.25rem;
}

/* WaniKani Level Badge */
.level-badge {
  font-size: 0.7rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  background: rgba(255, 255, 255, 0.6);
  padding: 0.15rem 0.4rem;
  border-radius: 4px;
  margin-bottom: 0.5rem;
  border: 1px solid rgba(0, 0, 0, 0.06);
}

/* Meanings text */
.kanji-meanings {
  font-size: 0.8rem;
  font-weight: 600;
  white-space: nowrap;
  text-overflow: ellipsis;
  overflow: hidden;
  max-width: 100%;
}

/* Tooltip/Readings Popup */
.kanji-readings {
  font-size: 0.75rem;
  margin-top: 0.25rem;
  opacity: 0.85;
  white-space: nowrap;
  text-overflow: ellipsis;
  overflow: hidden;
  max-width: 100%;
}

/* Empty State */
.empty-state {
  text-align: center;
  padding: 4rem 2rem;
  background: var(--panel-bg);
  border: 1px solid var(--border-color);
  border-radius: 12px;
  grid-column: 1 / -1;
  display: none;
}

.empty-state svg {
  color: var(--text-muted);
  margin-bottom: 1rem;
}

.empty-state h3 {
  font-family: var(--font-title);
  font-size: 1.35rem;
  margin-bottom: 0.5rem;
}

.empty-state p {
  color: var(--text-secondary);
}

/* Footer */
footer {
  text-align: center;
  margin-top: 4rem;
  padding-top: 2rem;
  border-top: 1px solid #e2e8f0;
  color: var(--text-muted);
  font-size: 0.85rem;
}

/* Mobile responsive */
@media (max-width: 768px) {
  body {
    padding: 1.5rem 1rem;
  }
  
  header {
    flex-direction: column;
    align-items: flex-start;
    gap: 1rem;
  }
  
  header h1 {
    font-size: 2rem;
  }

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

  .stat-item {
    flex: 1;
    min-width: 0;
    padding: 0.5rem 0.25rem;
  }

  .controls-row {
    flex-direction: column;
    align-items: stretch;
  }

  .tabs-group {
    justify-content: center;
  }

  .kanji-grid {
    grid-template-columns: repeat(auto-fill, minmax(100px, 1fr));
  }

  .kanji-char {
    font-size: 2.25rem;
  }
}
/* Modal Styles */
.modal {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.4);
  display: flex;
  justify-content: center;
  align-items: center;
  z-index: 1000;
}
.modal.hidden { display: none; }
.modal-content {
  background: var(--panel-bg);
  border-radius: 8px;
  padding: 1.5rem;
  max-width: 90%;
  max-height: 80vh;
  overflow-y: auto;
  box-shadow: var(--shadow-md);
  position: relative;
}
.modal-content .close {
  position: absolute;
  top: 0.5rem;
  right: 0.75rem;
  font-size: 1.5rem;
  cursor: pointer;
  color: var(--text-muted);
}
.wk-link {
  display: inline-block;
  margin: 0.5rem 0 0.25rem;
  padding: 0.3rem 0.85rem;
  font-size: 0.82rem;
  font-weight: 600;
  color: #fff;
  background: #00aaff;
  border-radius: 20px;
  text-decoration: none;
  transition: background 0.2s, transform 0.1s;
}
.wk-link:hover {
  background: #0088cc;
  transform: translateY(-1px);
}
.vocab-list {
  margin-top: 1rem;
}
.vocab-item {
  margin-bottom: 0.75rem;
  line-height: 1.4;
}
.vocab-level {
  display: inline-block;
  padding: 0.1rem 0.45rem;
  border-radius: 4px;
  font-size: 0.72rem;
  font-weight: 700;
  margin-left: 0.5rem;
  vertical-align: middle;
  letter-spacing: 0.02em;
}
.vocab-level.n5 { background: #2da84a; color: #fff; }
.vocab-level.n4 { background: #e07b00; color: #fff; }
.vocab-level.n3 { background: #3a7bd5; color: #fff; }
.vocab-word-link {
  color: inherit;
  text-decoration: none;
  border-bottom: 1px dotted #999;
  transition: border-color 0.15s, color 0.15s;
}
.vocab-word-link:hover {
  color: #0088cc;
  border-bottom-color: #0088cc;
}

/* Card badges & JLPT badges */
.card-badges {
  display: flex;
  gap: 0.35rem;
  justify-content: center;
  align-items: center;
  margin-bottom: 0.5rem;
}
.card-badges .level-badge,
.card-badges .jlpt-badge {
  margin-bottom: 0;
}
.jlpt-badge {
  font-size: 0.7rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  background: rgba(0, 0, 0, 0.07);
  color: var(--text-secondary);
  padding: 0.15rem 0.4rem;
  border-radius: 4px;
  border: 1px solid rgba(0, 0, 0, 0.08);
}

/* Modal Shortcuts */
.modal-shortcuts {
  margin-top: 1.5rem;
  padding-top: 0.75rem;
  border-top: 1px solid var(--border-color);
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 0.75rem;
  font-size: 0.75rem;
  color: var(--text-muted);
}
.modal-shortcuts span {
  display: flex;
  align-items: center;
  gap: 0.25rem;
}
kbd {
  background-color: #f1f5f9;
  border: 1px solid #cbd5e1;
  border-radius: 3px;
  box-shadow: 0 1px 0 rgba(0,0,0,0.15);
  color: var(--text-primary);
  display: inline-block;
  font-family: inherit;
  font-size: 0.7rem;
  font-weight: 600;
  line-height: 1.2;
  padding: 0.1rem 0.3rem;
  white-space: nowrap;
}

.modal-meaning-container {
  font-size: 0.95rem;
  color: var(--text-secondary);
  margin-bottom: 0.5rem;
}

.search-shortcut-hint {
  position: absolute;
  right: 0.75rem;
  top: 50%;
  transform: translateY(-50%);
  pointer-events: none;
  opacity: 0.6;
  transition: opacity 0.2s;
}

.search-box-wrapper:hover .search-shortcut-hint {
  opacity: 0.9;
}

.search-box:focus ~ .search-shortcut-hint {
  display: none;
}

.search-separator {
  grid-column: 1 / -1;
  width: 100%;
  margin: 1.5rem 0 0.5rem;
  border-bottom: 2px solid var(--border-color);
  text-align: left;
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  padding-bottom: 0.5rem;
}

.vocab-word-unclickable {
  color: var(--text-muted);
  cursor: help;
  border-bottom: 1px dashed rgba(0, 0, 0, 0.2);
}

/* Kanji highlighting in vocabulary modal */
.kanji-highlight {
  transition: color 0.15s ease;
}
.kanji-highlight.n5 {
  color: #2da84a;
}
.kanji-highlight.n4 {
  color: #e07b00;
}
.kanji-highlight.n3 {
  color: #3a7bd5;
}
.vocab-word-link:hover .kanji-highlight {
  color: #0088cc;
}