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

:root {
  --bg: #1a1a2e;
  --surface: #16213e;
  --surface-hover: #1a2745;
  --border: #2a3a5c;
  --text: #e0e0e0;
  --text-secondary: #8892a4;
  --accent: #4a9eff;
  --accent-hover: #6ab4ff;
  --danger: #ff6b6b;
  --danger-hover: #ff8787;
  --success: #51cf66;
  --radius: 8px;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  background: var(--bg);
  color: var(--text);
  min-height: 100vh;
}

.container {
  max-width: 860px;
  margin: 0 auto;
  padding: 40px 24px 60px;
}

h1 {
  font-size: 2rem;
  font-weight: 700;
  text-align: center;
  letter-spacing: 0.02em;
}

.subtitle {
  text-align: center;
  color: var(--text-secondary);
  margin-bottom: 8px;
  font-size: 0.95rem;
}

.rekit-about-link {
  display: block;
  text-align: center;
  margin-bottom: 32px;
  font-size: 0.78rem;
  color: var(--text-secondary);
  text-decoration: none;
  letter-spacing: 0.04em;
  opacity: 0.7;
  transition: opacity 0.15s ease;
}

.rekit-about-link:hover {
  opacity: 1;
}

html {
  scroll-behavior: smooth;
}

/* Pickers */
.pickers {
  display: flex;
  gap: 32px;
  justify-content: center;
  margin-bottom: 20px;
  flex-wrap: wrap;
}

.picker-group {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.picker-group label {
  font-size: 0.8rem;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.picker-group select {
  width: 280px;
  padding: 8px 12px;
  background: var(--surface);
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  font-size: 0.9rem;
  cursor: pointer;
  appearance: auto;
}

.picker-group select:focus {
  outline: none;
  border-color: var(--accent);
}

.preset-row {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-top: 4px;
}

.preset-row label {
  font-size: 0.7rem;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.preset-row select {
  flex: 1;
  padding: 5px 8px;
  background: var(--surface);
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  font-size: 0.8rem;
  cursor: pointer;
  appearance: auto;
}

.preset-row select:focus {
  outline: none;
  border-color: var(--accent);
}

/* Mapping Actions (Save / Load / Clear / Re-apply) */
.mapping-actions {
  display: flex;
  justify-content: center;
  gap: 8px;
  margin-bottom: 8px;
  flex-wrap: wrap;
}

.mapping-btn {
  display: inline-block;
  padding: 6px 14px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  color: var(--text);
  font-size: 0.82rem;
  cursor: pointer;
  transition: background 0.15s, border-color 0.15s, color 0.15s;
  text-align: center;
}

.mapping-btn:hover:not(:disabled),
.mapping-btn:focus-visible {
  background: var(--surface-hover);
  border-color: var(--accent);
  outline: none;
}

.mapping-btn:disabled {
  opacity: 0.35;
  cursor: default;
}

.mapping-btn-small {
  padding: 3px 10px;
  font-size: 0.75rem;
}

.preset-status {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 8px;
  margin-bottom: 16px;
  font-size: 0.78rem;
  color: var(--text-secondary);
  flex-wrap: wrap;
}

.preset-status-label {
  text-transform: uppercase;
  letter-spacing: 0.04em;
  font-size: 0.7rem;
}

.preset-filename {
  color: var(--accent);
  font-family: "SF Mono", "Menlo", monospace;
}

/* File Controls */
.file-controls {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 12px;
  position: relative;
}

.file-controls-left {
  display: flex;
  gap: 10px;
}

.add-file-btn {
  display: inline-block;
  padding: 7px 16px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  color: var(--text);
  font-size: 0.85rem;
  cursor: pointer;
  transition: background 0.15s;
}

.add-file-btn:hover {
  background: var(--surface-hover);
}

.clear-btn {
  padding: 7px 16px;
  background: transparent;
  border: 1px solid var(--danger);
  border-radius: var(--radius);
  color: var(--danger);
  font-size: 0.85rem;
  cursor: pointer;
  transition: all 0.15s;
}

.clear-btn:hover:not(:disabled) {
  background: var(--danger);
  color: #fff;
}

.clear-btn:disabled {
  opacity: 0.35;
  cursor: default;
}

.convert-btn {
  position: absolute;
  left: 50%;
  transform: translateX(-50%);
  padding: 8px 32px;
  background: var(--accent);
  border: none;
  border-radius: var(--radius);
  color: #fff;
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.15s;
}

.convert-btn:hover:not(:disabled) {
  background: var(--accent-hover);
}

.convert-btn:disabled {
  opacity: 0.35;
  cursor: default;
}

.file-count {
  margin-left: auto;
  font-size: 0.85rem;
  color: var(--text-secondary);
}

/* Drop Zone */
.drop-zone {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  min-height: 280px;
  position: relative;
  overflow: hidden;
  transition: border-color 0.15s, background 0.15s, box-shadow 0.15s;
}

.drop-zone.drag-active {
  border-color: var(--accent);
  background: rgba(74, 158, 255, 0.04);
  box-shadow: 0 0 0 3px rgba(74, 158, 255, 0.15);
}

.empty-state {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  height: 280px;
  color: var(--text-secondary);
  gap: 14px;
  cursor: pointer;
  transition: color 0.15s, background 0.15s;
}

.empty-state:hover,
.empty-state:focus-visible {
  color: var(--accent);
  background: rgba(74, 158, 255, 0.04);
  outline: none;
}

.empty-icon {
  width: 56px;
  height: 56px;
  stroke: currentColor;
}

.empty-state p {
  font-size: 0.9rem;
}

/* File List */
.file-list {
  padding: 0;
}

.file-row {
  display: flex;
  align-items: center;
  padding: 8px 14px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.04);
  font-size: 0.88rem;
  transition: background 0.1s;
}

.file-row:hover {
  background: var(--surface-hover);
}

.file-row .file-name {
  flex: 1;
}

.file-row .remove-btn {
  background: none;
  border: none;
  color: var(--text-secondary);
  font-size: 1rem;
  cursor: pointer;
  padding: 2px 6px;
  border-radius: 4px;
  transition: all 0.15s;
  line-height: 1;
}

.file-row .remove-btn:hover {
  color: var(--danger);
  transform: scale(1.2);
}

/* Converted file rows */
.file-row-wrap {
  border-bottom: 1px solid rgba(255, 255, 255, 0.04);
}

.file-row-wrap .file-row {
  border-bottom: none;
}

.file-row-converted {
  cursor: pointer;
}

.toggle-arrow {
  width: 16px;
  font-size: 0.7rem;
  color: var(--text-secondary);
  flex-shrink: 0;
  text-align: center;
}

.unmapped-badge {
  font-size: 0.75rem;
  color: var(--danger);
  background: rgba(255, 107, 107, 0.12);
  padding: 2px 8px;
  border-radius: 10px;
  margin-right: 8px;
  white-space: nowrap;
}

.unknown-badge {
  font-size: 0.75rem;
  color: #ffb74d;
  background: rgba(255, 167, 38, 0.12);
  padding: 2px 8px;
  border-radius: 10px;
  margin-right: 8px;
  white-space: nowrap;
}

/* Sub-sections inside expanded file rows */
.sub-section {
  border-top: 1px solid rgba(255, 255, 255, 0.04);
}

.sub-section summary {
  list-style: none;
  cursor: pointer;
  padding: 8px 14px 8px 22px;
  font-size: 0.78rem;
  color: var(--text-secondary);
  user-select: none;
  display: flex;
  align-items: center;
  gap: 8px;
}

.sub-section summary::-webkit-details-marker {
  display: none;
}

.sub-section summary::before {
  content: "▶";
  font-size: 0.65rem;
  color: var(--text-secondary);
  transition: transform 0.15s;
  display: inline-block;
}

.sub-section[open] summary::before {
  transform: rotate(90deg);
}

.sub-section-unmapped summary {
  color: var(--danger);
}

.sub-section-unknown summary {
  color: #ffb74d;
}

.sub-section-caption {
  padding: 0 14px 8px 36px;
  font-size: 0.75rem;
  color: var(--text-secondary);
  font-style: italic;
}

.sub-section-body {
  padding-bottom: 6px;
}

.unknown-list {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(70px, 1fr));
  gap: 2px 12px;
  padding: 0 14px 10px 36px;
}

.unknown-row {
  font-family: "SF Mono", "Menlo", monospace;
  font-size: 0.78rem;
  color: var(--text-secondary);
}

.file-ok {
  color: var(--success);
  margin-right: 8px;
  font-size: 0.9rem;
}

.file-error {
  font-size: 0.75rem;
  color: var(--danger);
  margin-right: 8px;
}

.unmapped-details {
  display: none;
  background: rgba(255, 255, 255, 0.02);
  border-top: 1px solid rgba(255, 255, 255, 0.04);
}

.file-row-wrap.expanded .unmapped-details {
  display: block;
}

.unmapped-detail-row {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 6px 14px 6px 36px;
  font-size: 0.8rem;
  color: var(--text-secondary);
  border-bottom: 1px solid rgba(255, 255, 255, 0.02);
}

.unmapped-detail-row:last-child {
  border-bottom: none;
}

.unmapped-note {
  font-family: "SF Mono", "Menlo", monospace;
  color: var(--text-secondary);
}

/* Routing rows */
.routed-row .route-src {
  flex: 1;
  min-width: 0;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.routed-row .route-src-note {
  font-family: "SF Mono", "Menlo", monospace;
  color: var(--text-secondary);
  width: 36px;
  text-align: right;
  flex-shrink: 0;
}

.routed-row .route-arrow {
  color: var(--text-secondary);
  flex-shrink: 0;
}

.routed-row .route-select {
  flex: 1.4;
  min-width: 180px;
  padding: 4px 6px;
  background: var(--surface);
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: 4px;
  font-size: 0.78rem;
  cursor: pointer;
}

.routed-row .route-select:focus {
  outline: none;
  border-color: var(--accent);
}

.routed-row.override .route-select {
  border-color: var(--accent);
}

/* Routing Panel (Mapping Editor) */
.routing-panel {
  margin-top: 18px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
}

.routing-panel summary {
  list-style: none;
  cursor: pointer;
  padding: 12px 14px;
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 0.85rem;
  color: var(--text);
  user-select: none;
}

.routing-panel summary::-webkit-details-marker {
  display: none;
}

.routing-panel summary::before {
  content: "▶";
  font-size: 0.7rem;
  color: var(--text-secondary);
  transition: transform 0.15s;
}

.routing-panel[open] summary::before {
  transform: rotate(90deg);
}

.routing-summary-label {
  flex: 1;
}

.routing-override-count {
  color: var(--accent);
  font-size: 0.78rem;
}

.routing-reset-btn {
  background: transparent;
  border: 1px solid var(--border);
  color: var(--text-secondary);
  border-radius: 4px;
  padding: 3px 10px;
  font-size: 0.75rem;
  cursor: pointer;
}

.routing-reset-btn:hover {
  border-color: var(--danger);
  color: var(--danger);
}

.routing-body {
  border-top: 1px solid var(--border);
  max-height: 400px;
  overflow-y: auto;
  background: rgba(0, 0, 0, 0.15);
}

.routing-body .routed-row {
  padding: 6px 14px;
}

/* Download Button */
.download-section {
  text-align: center;
  margin-top: 14px;
}

.download-btn {
  padding: 8px 32px;
  background: var(--surface);
  border: 1px solid var(--accent);
  border-radius: var(--radius);
  color: var(--accent);
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.15s;
}

.download-btn:hover {
  background: var(--accent);
  color: #fff;
}

/* Messages */
.message {
  margin-top: 14px;
  margin-bottom: 14px;
  padding: 10px 14px;
  border-radius: var(--radius);
  font-size: 0.85rem;
  white-space: pre-line;
}

.message.error {
  background: rgba(255, 107, 107, 0.1);
  color: var(--danger);
  border: 1px solid rgba(255, 107, 107, 0.2);
}

/* Help Section */
.help-section {
  margin-top: 32px;
  padding: 16px 20px;
  background: rgba(255, 255, 255, 0.02);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  color: var(--text-secondary);
  font-size: 0.82rem;
  line-height: 1.6;
}

.help-section h3 {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 10px;
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

.help-section ol {
  padding-left: 18px;
}

.help-section p {
  margin: 0 0 10px 0;
}

.help-section p:last-child {
  margin-bottom: 0;
}

.help-section li {
  margin-bottom: 6px;
}

.help-section li:last-child {
  margin-bottom: 0;
}

/* Utility */
.hidden {
  display: none !important;
}

/* Scrollbar */
.file-list::-webkit-scrollbar {
  width: 6px;
}

.file-list::-webkit-scrollbar-thumb {
  background: var(--border);
  border-radius: 3px;
}

/* Responsive */
@media (max-width: 640px) {
  .pickers {
    flex-direction: column;
    align-items: center;
  }
  .picker-group select {
    width: 100%;
    max-width: 320px;
  }
  .convert-btn {
    position: static;
    transform: none;
    width: 100%;
  }
  .file-controls {
    flex-wrap: wrap;
    justify-content: center;
  }
  .file-count {
    width: 100%;
    text-align: center;
  }
}