:root {
  --graph-primary: #7c3aed;
  --graph-secondary: #06b6d4;
  --graph-gradient: linear-gradient(135deg, #7c3aed 0%, #06b6d4 100%);
  --graph-bg: rgba(124, 58, 237, 0.06);
  --graph-bg-hover: rgba(124, 58, 237, 0.12);
  --graph-active-node: #facc15; /* Discovered state (yellow) */
  --graph-visited-node: #10b981; /* Visited state (green) */
}

.typing-text_graph {
  color: var(--graph-secondary);
  font-weight: 600;
}

/* Visualizer Layout overrides */
.visualizer-container {
  display: flex;
  gap: 2rem;
  margin-top: 2rem;
}

.visualizer-main-panel {
  flex: 1;
  min-width: 0;
}

.visualizer-sidebar {
  width: 320px;
  flex-shrink: 0;
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.visualizer-card {
  background: var(--glass-bg);
  border: 1px solid var(--glass-border);
  border-radius: 16px;
  padding: 1.5rem;
  backdrop-filter: blur(10px);
}

/* Canvas Area */
.canvas-wrapper {
  width: 100%;
  height: 500px;
  position: relative;
  overflow: hidden;
  border-radius: 12px;
  background: rgba(0, 0, 0, 0.4);
  border: 1px solid var(--glass-border);
  cursor: crosshair;
}

.canvas-placeholder-text {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  color: var(--text-secondary);
  font-size: 0.9rem;
  pointer-events: none;
  text-align: center;
}

/* SVG nodes and lines */
.svg-canvas {
  width: 100%;
  height: 100%;
  display: block;
}

.svg-node-group {
  cursor: grab;
}

.svg-node-group:active {
  cursor: grabbing;
}

.node-circle {
  fill: var(--dark-surface);
  stroke: var(--glass-border);
  stroke-width: 2.5;
  transition: fill 0.3s, stroke 0.3s, r 0.2s;
}

.node-circle:hover {
  stroke: var(--graph-secondary);
  r: 20;
}

.node-circle.active {
  fill: rgba(250, 204, 21, 0.15);
  stroke: var(--graph-active-node);
  stroke-width: 3.5;
}

.node-circle.visited {
  fill: rgba(16, 185, 129, 0.15);
  stroke: var(--graph-visited-node);
  stroke-width: 3;
}

.node-text {
  fill: var(--text-primary);
  font-family: "Orbitron", sans-serif;
  font-size: 0.75rem;
  font-weight: 700;
  text-anchor: middle;
  dominant-baseline: middle;
  pointer-events: none;
  user-select: none;
}

.edge-line {
  stroke: var(--glass-border);
  stroke-width: 2.5;
  transition: stroke 0.3s, stroke-width 0.3s;
}

.edge-line.active {
  stroke: var(--graph-secondary);
  stroke-width: 4;
}

.edge-line.visited {
  stroke: var(--graph-visited-node);
  stroke-width: 3.5;
}

.edge-weight-bg {
  fill: var(--dark-bg);
  stroke: var(--glass-border);
  stroke-width: 1;
  rx: 4;
  ry: 4;
}

.edge-weight-text {
  fill: var(--text-secondary);
  font-family: "Fira Code", monospace;
  font-size: 0.7rem;
  font-weight: 500;
  text-anchor: middle;
  dominant-baseline: middle;
  user-select: none;
}

/* Controls Grid */
.control-group {
  margin-bottom: 1.25rem;
}

.control-group label {
  display: block;
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 0.5rem;
}

.control-input {
  width: 100%;
  padding: 0.6rem 0.8rem;
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid var(--glass-border);
  color: var(--text-primary);
  font-family: "Poppins", sans-serif;
  font-size: 0.85rem;
  outline: none;
  transition: border-color 0.2s;
}

.control-input:focus {
  border-color: var(--graph-secondary);
}

.control-input option {
  background: var(--dark-surface);
  color: var(--text-primary);
}

.slider-custom {
  width: 100%;
  accent-color: var(--graph-secondary);
  cursor: pointer;
}

.val-display {
  float: right;
  font-family: "Fira Code", monospace;
  color: var(--graph-secondary);
  font-size: 0.8rem;
}

/* Mode Buttons */
.mode-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 0.6rem;
  margin-bottom: 1rem;
}

.mode-btn {
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid var(--glass-border);
  color: var(--text-secondary);
  padding: 0.5rem 0.75rem;
  border-radius: 8px;
  font-family: "Poppins", sans-serif;
  font-size: 0.8rem;
  font-weight: 500;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 0.4rem;
  justify-content: center;
  transition: all 0.2s ease;
}

.mode-btn:hover {
  background: var(--graph-bg);
  border-color: rgba(124, 58, 237, 0.4);
  color: var(--text-primary);
}

.mode-btn.active {
  background: var(--graph-gradient);
  border-color: transparent;
  color: white;
  box-shadow: 0 4px 12px rgba(124, 58, 237, 0.3);
}

/* Toggles */
.toggle-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 1rem;
}

.toggle-label {
  font-size: 0.85rem;
  color: var(--text-secondary);
}

/* Switch styling */
.switch {
  position: relative;
  display: inline-block;
  width: 44px;
  height: 22px;
}

.switch input {
  opacity: 0;
  width: 0;
  height: 0;
}

.slider-switch {
  position: absolute;
  cursor: pointer;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-color: rgba(255, 255, 255, 0.1);
  transition: .4s;
  border-radius: 34px;
  border: 1px solid var(--glass-border);
}

.slider-switch:before {
  position: absolute;
  content: "";
  height: 14px;
  width: 14px;
  left: 3px;
  bottom: 3px;
  background-color: var(--text-secondary);
  transition: .4s;
  border-radius: 50%;
}

input:checked + .slider-switch {
  background-color: var(--graph-primary);
}

input:checked + .slider-switch:before {
  transform: translateX(22px);
  background-color: white;
}

/* Playback Control Bar */
.btn-control-row {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0.5rem;
  margin-top: 1rem;
}

.btn-control {
  padding: 0.5rem;
  justify-content: center;
  display: flex;
  align-items: center;
  font-size: 0.85rem;
}

/* Visualizer logs */
.log-panel {
  max-height: 120px;
  overflow-y: auto;
  border-radius: 8px;
  padding: 0.75rem 1rem;
  background: rgba(0, 0, 0, 0.3);
  border: 1px solid var(--glass-border);
  font-family: "Fira Code", monospace;
  font-size: 0.78rem;
}

.log-entry {
  color: var(--text-secondary);
  line-height: 1.5;
  margin-bottom: 0.25rem;
}

.log-entry.active {
  color: var(--graph-secondary);
}

.log-entry.visited {
  color: var(--graph-visited-node);
}

/* Visualizer Visited Queue/Stack list */
.live-structure {
  display: flex;
  gap: 0.5rem;
  align-items: center;
  margin-top: 0.5rem;
  flex-wrap: wrap;
}

.structure-box {
  width: 32px;
  height: 32px;
  border-radius: 6px;
  background: var(--dark-surface);
  border: 1px solid var(--glass-border);
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: "Orbitron", sans-serif;
  font-size: 0.85rem;
  font-weight: bold;
  color: var(--text-primary);
  animation: scaleIn 0.2s ease forwards;
}

.structure-box.active {
  border-color: var(--graph-active-node);
  color: var(--graph-active-node);
}

.structure-box.visited {
  border-color: var(--graph-visited-node);
  color: var(--graph-visited-node);
}

@keyframes scaleIn {
  0% { transform: scale(0.7); opacity: 0; }
  100% { transform: scale(1); opacity: 1; }
}

.structure-arrow {
  color: var(--text-secondary);
  font-size: 0.75rem;
}

/* Complexity Grid */
.complexity-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 0.75rem;
  margin-top: 1rem;
}

.complexity-card-mini {
  background: rgba(255, 255, 255, 0.02);
  border: 1px solid var(--glass-border);
  border-radius: 8px;
  padding: 0.75rem;
  text-align: center;
}

.complexity-card-mini h5 {
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-secondary);
  margin-bottom: 0.25rem;
}

.complexity-card-mini p {
  font-family: "Fira Code", monospace;
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--graph-secondary);
  margin: 0;
}

/* responsive overrides */
@media (max-width: 1024px) {
  .visualizer-container {
    flex-direction: column;
  }

  .visualizer-sidebar {
    width: 100%;
  }
}

@media (max-width: 768px) {
  .canvas-wrapper {
    height: 400px;
  }
}