/* LDPC BG2 H-Matrix tutorial — dark theme, glowing accents */
#ldpc-bg2-tutorial {
  max-width: 800px;
  margin: 0 auto;
  font-family: 'Courier New', Courier, monospace;
  background: #0a0a0e;
  color: #e0e0e8;
  padding: 12px;
  border-radius: 8px;
  box-sizing: border-box;
}

#ldpc-bg2-tutorial * {
  box-sizing: border-box;
}

#ldpc-bg2-tutorial .ldpc-step-flow {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  margin-bottom: 12px;
  flex-wrap: wrap;
}

#ldpc-bg2-tutorial .ldpc-step-item {
  padding: 6px 12px;
  background: #1a1a24;
  border: 1px solid #2a2a38;
  border-radius: 6px;
  font-size: 12px;
}

#ldpc-bg2-tutorial .ldpc-step-item.active {
  border-color: #0cf;
  box-shadow: 0 0 12px rgba(0, 204, 255, 0.4);
  background: #1a2430;
}

#ldpc-bg2-tutorial .ldpc-step-arrow {
  color: #666;
  font-size: 14px;
}

#ldpc-bg2-tutorial .ldpc-step-flow .ldpc-tbs-inline {
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

#ldpc-bg2-tutorial .ldpc-step-flow .ldpc-tbs-inline label {
  color: #a0a0b0;
  font-size: 12px;
  white-space: nowrap;
}

#ldpc-bg2-tutorial .ldpc-step-flow .ldpc-tbs-inline input[type="number"] {
  width: 72px;
  padding: 4px 6px;
  background: #1a1a24;
  border: 1px solid #3a3a4a;
  border-radius: 4px;
  color: #e0e0e8;
  font-family: 'Courier New', monospace;
  font-size: 12px;
}

#ldpc-bg2-tutorial .ldpc-step-flow .ldpc-tbs-inline input:focus {
  outline: none;
  border-color: #0cf;
  box-shadow: 0 0 8px rgba(0, 204, 255, 0.3);
}

#ldpc-bg2-tutorial .ldpc-ils-section {
  margin-bottom: 12px;
  padding: 10px 12px;
  background: #1e1e28;
  border: 1px solid #3a3a4a;
  border-radius: 6px;
  color: #e8e8f0;
}

#ldpc-bg2-tutorial .ldpc-ils-title {
  font-size: 12px;
  color: #0cf;
  margin-bottom: 8px;
}

#ldpc-bg2-tutorial .ldpc-ils-process {
  margin-bottom: 10px;
  font-size: 11px;
  color: #e0e0ec;
}

#ldpc-bg2-tutorial .ldpc-ils-process-title {
  font-weight: bold;
  margin-bottom: 4px;
  color: #e8e8f0;
}

#ldpc-bg2-tutorial .ldpc-ils-steps {
  margin: 0 0 8px 18px;
  padding: 0;
}

#ldpc-bg2-tutorial .ldpc-ils-steps li {
  margin-bottom: 2px;
}

#ldpc-bg2-tutorial .ldpc-calc-steps {
  margin-top: 8px;
  padding: 8px;
  background: #242430;
  border-left: 3px solid #0cf;
  border-radius: 4px;
  font-size: 11px;
  color: #e8e8f0;
}

#ldpc-bg2-tutorial .ldpc-zc-detected {
  color: #ff0;
  font-weight: bold;
}

#ldpc-bg2-tutorial .ldpc-ils-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 11px;
  color: #e8e8f0;
}

#ldpc-bg2-tutorial .ldpc-ils-table th,
#ldpc-bg2-tutorial .ldpc-ils-table td {
  border: 1px solid #3a3a4a;
  padding: 6px 10px;
  text-align: left;
  color: #e8e8f0;
}

#ldpc-bg2-tutorial .ldpc-ils-table th {
  background: #2a2a36;
  color: #0cf;
}

#ldpc-bg2-tutorial .ldpc-ils-table tbody td {
  background: #1e1e28;
  color: #e8e8f0;
}

#ldpc-bg2-tutorial .ldpc-ils-table tbody tr.selected td {
  background: rgba(0, 204, 255, 0.2);
  color: #fff;
}

#ldpc-bg2-tutorial .ldpc-ils-table tbody tr.selected {
  border-color: #0cf;
  box-shadow: 0 0 8px rgba(0, 204, 255, 0.3);
}

#ldpc-bg2-tutorial .ldpc-controls {
  display: flex;
  flex-wrap: wrap;
  gap: 12px 20px;
  align-items: center;
  justify-content: center;
  margin-bottom: 12px;
}

#ldpc-bg2-tutorial .ldpc-control-row {
  display: flex;
  align-items: center;
  gap: 8px;
}

#ldpc-bg2-tutorial .ldpc-control-row label {
  color: #a0a0b0;
  font-size: 12px;
  white-space: nowrap;
}

#ldpc-bg2-tutorial .ldpc-control-row input[type="number"],
#ldpc-bg2-tutorial .ldpc-control-row select {
  width: 72px;
  padding: 4px 6px;
  background: #1a1a24;
  border: 1px solid #3a3a4a;
  border-radius: 4px;
  color: #e0e0e8;
  font-family: 'Courier New', monospace;
  font-size: 12px;
}

#ldpc-bg2-tutorial .ldpc-control-row input:focus,
#ldpc-bg2-tutorial .ldpc-control-row select:focus {
  outline: none;
  border-color: #0cf;
  box-shadow: 0 0 8px rgba(0, 204, 255, 0.3);
}

#ldpc-bg2-tutorial .ldpc-btn {
  padding: 6px 14px;
  background: #1a2a3a;
  border: 1px solid #0cf;
  border-radius: 4px;
  color: #0cf;
  font-family: 'Courier New', monospace;
  font-size: 12px;
  cursor: pointer;
}

#ldpc-bg2-tutorial .ldpc-btn:hover {
  background: #0cf;
  color: #0a0a0e;
  box-shadow: 0 0 12px rgba(0, 204, 255, 0.5);
}

#ldpc-bg2-tutorial .ldpc-tooltip {
  margin-bottom: 12px;
  padding: 10px 12px;
  background: #14141c;
  border-left: 4px solid #0cf;
  border-radius: 4px;
  font-size: 12px;
  color: #b0b0c0;
}

#ldpc-bg2-tutorial .ldpc-layout {
  display: flex;
  gap: 12px;
  align-items: flex-start;
  flex-wrap: wrap;
}

#ldpc-bg2-tutorial .ldpc-bg-label,
#ldpc-bg2-tutorial .ldpc-canvas-label {
  font-size: 12px;
  color: #a0a0b0;
  margin-bottom: 6px;
}

#ldpc-bg2-tutorial .ldpc-shift-panel {
  margin-bottom: 12px;
}

#ldpc-bg2-tutorial .ldpc-shift-label {
  font-size: 12px;
  color: #a0a0b0;
  margin-bottom: 6px;
}

#ldpc-bg2-tutorial .ldpc-shift-wrapper {
  overflow: auto;
  max-height: 420px;
  background: #0e0e14;
  border: 1px solid #2a2a38;
  border-radius: 6px;
  padding: 4px;
}

#ldpc-bg2-tutorial .ldpc-3gpp-table {
  border-collapse: collapse;
  font-size: 11px;
  width: 100%;
  color: #e8e8f0;
}

#ldpc-bg2-tutorial .ldpc-3gpp-caption {
  caption-side: top;
  text-align: left;
  padding: 4px 0 6px 0;
  font-size: 11px;
  color: #a0a0b0;
}

#ldpc-bg2-tutorial .ldpc-3gpp-table th,
#ldpc-bg2-tutorial .ldpc-3gpp-table td {
  border: 1px solid #3a3a4a;
  padding: 4px 8px;
  text-align: center;
}

#ldpc-bg2-tutorial .ldpc-3gpp-table thead th {
  background: #1a2430;
  color: #0cf;
  font-weight: bold;
}

#ldpc-bg2-tutorial .ldpc-3gpp-hbg { text-align: center; }
#ldpc-bg2-tutorial .ldpc-3gpp-vij { text-align: center; }

#ldpc-bg2-tutorial .ldpc-3gpp-th {
  min-width: 2.5em;
}

#ldpc-bg2-tutorial .ldpc-3gpp-ls-header {
  font-weight: normal;
  color: #a0a0b0;
  font-size: 10px;
}

#ldpc-bg2-tutorial .ldpc-3gpp-ls {
  min-width: 2.2em;
  font-size: 10px;
}

#ldpc-bg2-tutorial .ldpc-3gpp-rowi {
  vertical-align: middle;
  font-weight: bold;
  background: #1e1e28;
}

#ldpc-bg2-tutorial .ldpc-3gpp-colj {
  min-width: 2.5em;
}

#ldpc-bg2-tutorial .ldpc-3gpp-v .ldpc-zc-detected {
  color: #ff0;
  font-weight: bold;
}

#ldpc-bg2-tutorial .ldpc-legend {
  display: flex;
  gap: 16px;
  margin-bottom: 6px;
  font-size: 10px;
  flex-wrap: wrap;
}

#ldpc-bg2-tutorial .ldpc-legend-item {
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

#ldpc-bg2-tutorial .ldpc-legend-item.systematic::before {
  content: '';
  display: inline-block;
  width: 12px;
  height: 12px;
  border-radius: 2px;
  background: rgba(0, 180, 220, 0.35);
  border: 1px solid rgba(0, 200, 255, 0.5);
}

#ldpc-bg2-tutorial .ldpc-legend-item.parity::before {
  content: '';
  display: inline-block;
  width: 12px;
  height: 12px;
  border-radius: 2px;
  background: rgba(180, 100, 220, 0.25);
  border: 1px solid rgba(180, 120, 255, 0.4);
}

#ldpc-bg2-tutorial .ldpc-bg-cell.systematic {
  background: rgba(0, 180, 220, 0.12);
}

#ldpc-bg2-tutorial .ldpc-bg-cell.parity {
  background: rgba(180, 100, 220, 0.08);
}

#ldpc-bg2-tutorial .ldpc-bg-cell.systematic.occupied {
  background: rgba(0, 180, 220, 0.22);
}

#ldpc-bg2-tutorial .ldpc-bg-cell.parity.occupied {
  background: rgba(180, 100, 220, 0.18);
}

#ldpc-bg2-tutorial .ldpc-bg-panel {
  flex: 0 0 auto;
  max-width: 100%;
}

#ldpc-bg2-tutorial .ldpc-bg-wrapper {
  overflow: auto;
  max-height: 420px;
  background: #0e0e14;
  border: 1px solid #2a2a38;
  border-radius: 6px;
  padding: 4px;
}

#ldpc-bg2-tutorial .ldpc-bg-grid {
  border-collapse: collapse;
  font-size: 9px;
}

#ldpc-bg2-tutorial .ldpc-bg-cell {
  width: 18px;
  height: 14px;
  min-width: 18px;
  min-height: 14px;
  padding: 0 2px;
  text-align: center;
  border: 1px solid #1e1e2a;
  background: #12121a;
  color: #606078;
  cursor: default;
}

#ldpc-bg2-tutorial .ldpc-bg-cell.occupied {
  background: #1a2430;
  color: #8ae;
}

#ldpc-bg2-tutorial .ldpc-bg-cell.hover,
#ldpc-bg2-tutorial .ldpc-bg-cell:hover {
  background: #0a2030;
  border-color: #0cf;
  box-shadow: 0 0 8px rgba(0, 204, 255, 0.5);
  color: #0cf;
  z-index: 1;
}

#ldpc-bg2-tutorial .ldpc-summary-panel {
  margin-bottom: 10px;
  font-family: 'Courier New', Courier, monospace;
  font-size: 11px;
}

#ldpc-bg2-tutorial .ldpc-summary-table {
  width: 100%;
  border-collapse: collapse;
  color: #e8e8f0;
}

#ldpc-bg2-tutorial .ldpc-summary-table th,
#ldpc-bg2-tutorial .ldpc-summary-table td {
  border: 1px solid #3a3a4a;
  padding: 6px 8px;
  text-align: left;
  background: #1a1a24;
}

#ldpc-bg2-tutorial .ldpc-summary-table th {
  color: #0cf;
  font-weight: bold;
}

#ldpc-bg2-tutorial .ldpc-summary-table td:nth-child(2) {
  color: #8ae;
  font-weight: bold;
}

#ldpc-bg2-tutorial .ldpc-canvas-panel {
  flex: 1 1 400px;
  min-width: 280px;
}

#ldpc-bg2-tutorial .ldpc-canvas-wrapper {
  position: relative;
  width: 100%;
  max-width: 800px;
  height: 500px;
  background: #111;
  border: 1px solid #2a2a38;
  border-radius: 6px;
  overflow: hidden;
  transition: box-shadow 0.3s ease, border-color 0.3s ease;
}

#ldpc-bg2-tutorial .ldpc-hmatrix-controls {
  position: absolute;
  top: 8px;
  right: 8px;
  z-index: 10;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
  pointer-events: none;
}

#ldpc-bg2-tutorial .ldpc-hmatrix-controls .ldpc-hctrl-btn {
  pointer-events: auto;
  min-width: 28px;
  min-height: 28px;
  width: 28px;
  height: 28px;
  padding: 0 4px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 2px;
  background: rgba(20, 20, 28, 0.92);
  border: 1px solid #2a2a38;
  border-radius: 4px;
  color: #0cf;
  cursor: pointer;
  font-size: 9px;
  font-family: inherit;
  transition: background 0.15s, border-color 0.15s, color 0.15s;
}

#ldpc-bg2-tutorial .ldpc-hmatrix-controls .ldpc-hctrl-btn:has(span) {
  width: auto;
}

#ldpc-bg2-tutorial .ldpc-hmatrix-controls .ldpc-hctrl-btn:hover {
  background: rgba(0, 204, 255, 0.2);
  border-color: #0cf;
  color: #fff;
}

#ldpc-bg2-tutorial .ldpc-hmatrix-controls .ldpc-hctrl-btn:active {
  background: rgba(0, 204, 255, 0.35);
}

#ldpc-bg2-tutorial .ldpc-hmatrix-controls .ldpc-hctrl-icon {
  width: 14px;
  height: 14px;
  flex-shrink: 0;
}

#ldpc-bg2-tutorial .ldpc-hmatrix-controls .ldpc-hctrl-btn span {
  line-height: 1;
}

#ldpc-bg2-tutorial .ldpc-hmatrix-controls .ldpc-hctrl-sep {
  width: 100%;
  height: 6px;
  border-top: 1px solid rgba(42, 42, 56, 0.8);
  margin: 2px 0;
}

#ldpc-bg2-tutorial .ldpc-hmatrix-controls .ldpc-hctrl-pan-row {
  display: flex;
  gap: 4px;
  align-items: center;
  justify-content: center;
}

#ldpc-bg2-tutorial .ldpc-canvas-wrapper.ldpc-success {
  border-color: #0c4;
  box-shadow: 0 0 20px rgba(0, 204, 68, 0.5);
  animation: ldpc-success-pulse 1.5s ease-out;
}

@keyframes ldpc-success-pulse {
  0% { box-shadow: 0 0 24px rgba(0, 204, 68, 0.7); }
  50% { box-shadow: 0 0 16px rgba(0, 204, 68, 0.4); }
  100% { box-shadow: 0 0 8px rgba(0, 204, 68, 0.2); }
}

#ldpc-bg2-tutorial #hMatrixCanvas {
  display: block;
  width: 100%;
  height: 100%;
  background: #111;
}

/* Circulant popup overlay */
.ldpc-circulant-overlay {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(0, 0, 0, 0.75);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 10000;
  font-family: 'Courier New', Courier, monospace;
}

.ldpc-circulant-box {
  background: #1a1a24;
  border: 1px solid #0cf;
  border-radius: 8px;
  padding: 16px;
  box-shadow: 0 0 24px rgba(0, 204, 255, 0.3);
  max-width: 95vw;
}

.ldpc-circulant-title {
  color: #0cf;
  font-size: 14px;
  margin-bottom: 10px;
}

.ldpc-detail-meta {
  font-family: 'Courier New', Courier, monospace;
  font-size: 12px;
  margin-bottom: 12px;
  padding: 10px;
  background: #12121a;
  border-radius: 4px;
  border: 1px solid #2a2a38;
  color: #e0e0ec;
}

.ldpc-detail-row {
  margin-bottom: 6px;
}

.ldpc-detail-row:last-child {
  margin-bottom: 0;
}

.ldpc-detail-label {
  color: #a0a0b0;
  margin-right: 8px;
}

.ldpc-detail-value {
  color: #0cf;
  font-weight: bold;
}

.ldpc-detail-formula .ldpc-detail-value {
  color: #8ae;
  font-weight: normal;
}

.ldpc-detail-canvas-wrap {
  margin-bottom: 12px;
}

.ldpc-detail-canvas-wrap canvas {
  display: block;
  background: #fff;
  border-radius: 4px;
}

.ldpc-circulant-box canvas {
  display: block;
  background: #fff;
  border-radius: 4px;
  margin-bottom: 12px;
}

.ldpc-close-popup {
  display: block;
  width: 100%;
  padding: 8px;
  background: #2a2a38;
  border: 1px solid #0cf;
  border-radius: 4px;
  color: #0cf;
  font-family: 'Courier New', monospace;
  cursor: pointer;
}

.ldpc-close-popup:hover {
  background: #0cf;
  color: #0a0a0e;
}

/* Blended scrollbars for tutorial scroll areas */
#ldpc-bg2-tutorial .ldpc-shift-wrapper,
#ldpc-bg2-tutorial .ldpc-bg-wrapper,
#ldpc-bg2-tutorial .ldpc-ils-section,
#ldpc-bg2-tutorial .ldpc-bit-viewer {
  scrollbar-width: thin;
  scrollbar-gutter: stable;
  scrollbar-color: rgba(90, 90, 110, 0.5) rgba(20, 20, 28, 0.98);
}

#ldpc-bg2-tutorial .ldpc-shift-wrapper::-webkit-scrollbar,
#ldpc-bg2-tutorial .ldpc-bg-wrapper::-webkit-scrollbar,
#ldpc-bg2-tutorial .ldpc-bit-viewer::-webkit-scrollbar {
  width: 6px;
  height: 6px;
}

#ldpc-bg2-tutorial .ldpc-shift-wrapper::-webkit-scrollbar-track,
#ldpc-bg2-tutorial .ldpc-bg-wrapper::-webkit-scrollbar-track,
#ldpc-bg2-tutorial .ldpc-bit-viewer::-webkit-scrollbar-track {
  background: transparent;
  border-radius: 3px;
}

#ldpc-bg2-tutorial .ldpc-shift-wrapper::-webkit-scrollbar-thumb,
#ldpc-bg2-tutorial .ldpc-bg-wrapper::-webkit-scrollbar-thumb,
#ldpc-bg2-tutorial .ldpc-bit-viewer::-webkit-scrollbar-thumb {
  background: rgba(80, 80, 96, 0.4);
  border-radius: 3px;
}

#ldpc-bg2-tutorial .ldpc-shift-wrapper::-webkit-scrollbar-thumb:hover,
#ldpc-bg2-tutorial .ldpc-bg-wrapper::-webkit-scrollbar-thumb:hover,
#ldpc-bg2-tutorial .ldpc-bit-viewer::-webkit-scrollbar-thumb:hover {
  background: rgba(100, 100, 120, 0.55);
}

#ldpc-bg2-tutorial .ldpc-shift-wrapper::-webkit-scrollbar-corner,
#ldpc-bg2-tutorial .ldpc-bg-wrapper::-webkit-scrollbar-corner,
#ldpc-bg2-tutorial .ldpc-bit-viewer::-webkit-scrollbar-corner {
  background: transparent;
}

/* Codeword / Encoding section */
#ldpc-bg2-tutorial .ldpc-encoding-section {
  margin-top: 20px;
  padding: 15px;
  background: #14141f;
  border: 1px solid #333;
  border-radius: 8px;
}

#ldpc-bg2-tutorial .ldpc-encoding-title {
  font-size: 13px;
  color: #0cf;
  margin-bottom: 12px;
}

#ldpc-bg2-tutorial .ldpc-encoding-controls {
  display: flex;
  flex-direction: column;
  gap: 8px;
  margin-bottom: 12px;
}

#ldpc-bg2-tutorial .ldpc-encoding-controls label {
  color: #a0a0b0;
  font-size: 12px;
}

#ldpc-bg2-tutorial .ldpc-tb-count {
  color: #8ae;
  font-size: 11px;
  font-weight: normal;
  margin-left: 6px;
}

#ldpc-bg2-tutorial .ldpc-tb-count.ldpc-tb-over {
  color: #f88;
}

#ldpc-bg2-tutorial .ldpc-tb-input {
  width: 100%;
  background: #000;
  color: #0f0;
  border: 1px solid #0cf;
  padding: 8px;
  font-family: monospace;
  margin-bottom: 0;
  font-size: 12px;
  border-radius: 4px;
  resize: vertical;
}

#ldpc-bg2-tutorial .ldpc-tb-input:focus {
  outline: none;
  box-shadow: 0 0 8px rgba(0, 204, 255, 0.3);
}

#ldpc-bg2-tutorial .ldpc-syndrome-status {
  margin-bottom: 10px;
  padding: 8px 12px;
  border-radius: 4px;
  font-size: 12px;
  font-weight: bold;
}

#ldpc-bg2-tutorial .ldpc-syndrome-status.valid {
  background: rgba(0, 200, 80, 0.2);
  border: 1px solid #0c4;
  color: #0f4;
}

#ldpc-bg2-tutorial .ldpc-syndrome-status.invalid {
  background: rgba(200, 0, 0, 0.2);
  border: 1px solid #c00;
  color: #f66;
}

#ldpc-bg2-tutorial .ldpc-impairment-group {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px 14px;
  margin-bottom: 12px;
  padding: 10px 12px;
  background: #1a1a24;
  border: 1px solid #2a2a38;
  border-radius: 6px;
}

#ldpc-bg2-tutorial .ldpc-impairment-title {
  font-size: 12px;
  color: #a0a0b0;
  margin-right: 6px;
}

#ldpc-bg2-tutorial .ldpc-btn-impair {
  background: #2a1a1a;
  border-color: #c44;
  color: #f88;
}

#ldpc-bg2-tutorial .ldpc-btn-impair:hover {
  background: #c44;
  color: #fff;
  box-shadow: 0 0 10px rgba(200, 68, 68, 0.5);
}

#ldpc-bg2-tutorial .ldpc-btn-fix {
  background: #1a2a1a;
  border-color: #4c4;
  color: #8f8;
}

#ldpc-bg2-tutorial .ldpc-btn-fix:hover {
  background: #4c4;
  color: #0a0a0e;
  box-shadow: 0 0 10px rgba(68, 200, 68, 0.5);
}

#ldpc-bg2-tutorial .ldpc-c-ribbon-wrap {
  margin-bottom: 10px;
}

#ldpc-bg2-tutorial .ldpc-c-ribbon-label {
  font-size: 11px;
  color: #a0a0b0;
  margin-bottom: 6px;
}

#ldpc-bg2-tutorial .ldpc-c-ribbon {
  display: flex;
  height: 40px;
  margin-top: 4px;
  border: 1px solid #444;
  border-radius: 4px;
  overflow: hidden;
  font-size: 10px;
  line-height: 40px;
  text-align: center;
}

#ldpc-bg2-tutorial .ribbon-section.systematic {
  background: rgba(0, 204, 255, 0.3);
  border-right: 2px solid #0cf;
  color: #fff;
}

#ldpc-bg2-tutorial .ribbon-section.parity {
  background: rgba(180, 120, 255, 0.2);
  color: #d8b0ff;
}

#ldpc-bg2-tutorial .ldpc-c-length {
  margin-top: 6px;
  font-size: 11px;
  color: #8ae;
}

#ldpc-bg2-tutorial .ldpc-c-length b {
  color: #0cf;
}

#ldpc-bg2-tutorial .ldpc-codeword-content {
  margin-top: 8px;
}

#ldpc-bg2-tutorial .ldpc-bit-viewer {
  display: flex;
  flex-wrap: wrap;
  gap: 2px;
  max-height: 150px;
  overflow-y: auto;
  background: #000;
  padding: 10px;
  border: 1px solid #333;
  border-radius: 4px;
  font-family: 'Courier New', monospace;
  font-size: 10px;
  margin-top: 8px;
}

/* Block-aligned bit viewer: one row per block (Zc bits per row), labels Block 0..51 */
#ldpc-bg2-tutorial .ldpc-bit-viewer.ldpc-bit-viewer-grid {
  display: flex;
  flex-direction: column;
  flex-wrap: nowrap;
  gap: 0;
  max-height: 280px;
}

#ldpc-bg2-tutorial .ldpc-bit-viewer-grid .block-row {
  display: flex;
  align-items: center;
  margin-bottom: 10px;
  gap: 8px;
  min-height: 24px;
}

#ldpc-bg2-tutorial .ldpc-bit-viewer-grid .block-row:last-child {
  margin-bottom: 4px;
}

#ldpc-bg2-tutorial .ldpc-bit-viewer-grid .block-label {
  min-width: 56px;
  font-size: 10px;
  color: #a0a0b0;
  flex-shrink: 0;
}

#ldpc-bg2-tutorial .ldpc-bit-viewer-grid .block-row.systematic-row .block-label {
  color: #0cf;
}

#ldpc-bg2-tutorial .ldpc-bit-viewer-grid .block-row.parity-row .block-label {
  color: #b8f;
}

#ldpc-bg2-tutorial .ldpc-bit-viewer-grid .block-bits {
  display: grid;
  gap: 4px;
  flex: 1;
  min-width: 0;
}

#ldpc-bg2-tutorial .ldpc-bit-viewer-grid .block-row.systematic-row .block-bits {
  border-left: 2px solid rgba(0, 204, 255, 0.4);
  padding-left: 6px;
}

#ldpc-bg2-tutorial .ldpc-bit-viewer-grid .block-row.parity-row .block-bits {
  border-left: 2px solid rgba(180, 120, 255, 0.4);
  padding-left: 6px;
}

#ldpc-bg2-tutorial .ldpc-bit {
  width: 12px;
  height: 16px;
  min-width: 12px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  cursor: pointer;
  border-radius: 2px;
  border: 1px solid transparent;
  user-select: none;
}

#ldpc-bg2-tutorial .ldpc-bit.bit-s {
  color: #0cf;
  background: rgba(0, 204, 255, 0.1);
}

#ldpc-bg2-tutorial .ldpc-bit.bit-p {
  color: #b8f;
  background: rgba(184, 134, 255, 0.1);
}

#ldpc-bg2-tutorial .ldpc-bit:hover {
  border-color: #0cf;
  box-shadow: 0 0 5px rgba(0, 204, 255, 0.4);
}

#ldpc-bg2-tutorial .ldpc-bit.flipped {
  background: #f00 !important;
  color: #fff !important;
  box-shadow: 0 0 5px #f00;
  border-color: #f00;
}

#ldpc-bg2-tutorial .ldpc-bit.in-failed-check {
  background: rgba(255, 100, 100, 0.35) !important;
  border-color: #f66;
  box-shadow: 0 0 4px rgba(255, 0, 0, 0.5);
}

#ldpc-bg2-tutorial .ldpc-c-bitstrip {
  display: flex;
  flex-wrap: wrap;
  gap: 2px;
  margin-top: 8px;
  font-family: 'Courier New', monospace;
  font-size: 11px;
}

#ldpc-bg2-tutorial .ldpc-c-bit {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 18px;
  height: 22px;
  padding: 0 4px;
  background: #1a1a24;
  border: 1px solid #3a3a4a;
  border-radius: 3px;
  color: #0f0;
  cursor: pointer;
  user-select: none;
}

#ldpc-bg2-tutorial .ldpc-c-bit:hover {
  border-color: #0cf;
  box-shadow: 0 0 6px rgba(0, 204, 255, 0.4);
  color: #0cf;
}

#ldpc-bg2-tutorial .ldpc-c-bit.systematic {
  background: rgba(0, 204, 255, 0.15);
  border-color: rgba(0, 204, 255, 0.4);
}

#ldpc-bg2-tutorial .ldpc-c-bit.parity {
  background: rgba(180, 120, 255, 0.12);
  border-color: rgba(180, 120, 255, 0.35);
}

#ldpc-bg2-tutorial .ldpc-c-bit-ellipsis {
  color: #666;
  padding: 0 4px;
  line-height: 22px;
}

#ldpc-bg2-tutorial .ldpc-edu-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 11px;
  margin-top: 12px;
  color: #e8e8f0;
}

#ldpc-bg2-tutorial .ldpc-edu-table caption {
  text-align: left;
  margin-bottom: 6px;
  color: #a0a0b0;
}

#ldpc-bg2-tutorial .ldpc-edu-table th,
#ldpc-bg2-tutorial .ldpc-edu-table td {
  border: 1px solid #3a3a4a;
  padding: 6px 10px;
  text-align: left;
}

#ldpc-bg2-tutorial .ldpc-edu-table th {
  background: #2a2a36;
  color: #0cf;
}

#ldpc-bg2-tutorial .ldpc-edu-table td {
  background: #1a1a24;
}

/* Validity Check Procedure panel — code/terminal style */
#ldpc-bg2-tutorial .ldpc-validity-procedure-wrap {
  margin-bottom: 10px;
}

#ldpc-bg2-tutorial .ldpc-validity-panel {
  background: #0e0e14;
  border: 1px solid #2a2a38;
  padding: 15px;
  margin-bottom: 10px;
  border-radius: 6px;
  font-size: 11px;
  font-family: 'Courier New', Courier, monospace;
  color: #a0a0b0;
}

#ldpc-bg2-tutorial .ldpc-validity-panel h4 {
  color: #e0e0e8;
  margin: 0 0 12px 0;
  font-size: 12px;
}

#ldpc-bg2-tutorial .ldpc-validity-panel .proc-step {
  margin-bottom: 10px;
  border-left: 2px solid #333;
  padding-left: 10px;
}

#ldpc-bg2-tutorial .ldpc-validity-panel .proc-step p {
  margin: 4px 0 0 0;
  color: #a0a0b0;
}

#ldpc-bg2-tutorial .ldpc-validity-panel .step-label {
  display: block;
  color: #0cf;
  font-weight: bold;
  margin-bottom: 4px;
}

#ldpc-bg2-tutorial .ldpc-validity-panel .pass-text {
  color: #0f0;
  text-shadow: 0 0 5px rgba(0, 255, 0, 0.5);
}

#ldpc-bg2-tutorial .ldpc-validity-panel .fail-text {
  color: #f33;
  text-shadow: 0 0 5px rgba(255, 50, 50, 0.5);
}

#ldpc-bg2-tutorial .ldpc-validity-panel .proc-summary {
  background: rgba(255, 255, 255, 0.05);
  padding: 8px;
  text-align: center;
  font-weight: bold;
  border-radius: 4px;
  margin-top: 10px;
  color: #e0e0e8;
}