:root {
  --primary-color: #2563eb;
  --primary-hover: #1d4ed8;
  --background-color: #0f172a;
  --surface-color: #1e293b;
  --panel-color: #334155;
  --text-color: #f1f5f9;
  --text-muted: #94a3b8;

  /* Maze Colors */
  --wall-color: #475569;
  --wall-side: #334155;
  --floor-color: #0f172a;
  --path-color: #8b5cf6;
  --visited-color: #10b981;
  --active-color: #f59e0b;
  --start-color: #3b82f6;
  --end-color: #ef4444;
}

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

body {
  font-family: 'Outfit', sans-serif;
  background-color: var(--background-color);
  color: var(--text-color);
  min-height: 100vh;
  display: flex;
  justify-content: center;
  padding: 1.5rem;
  overflow-x: hidden;
}

.app-container {
  width: 100%;
  max-width: 1400px;
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.title-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  flex-wrap: wrap;
}

h1 {
  font-size: 2.5rem;
  background: linear-gradient(90deg, #60a5fa, #c084fc);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  margin: 0;
  text-shadow: 0 0 20px rgba(96, 165, 250, 0.3);
}

.tagline {
  color: var(--text-muted);
}

.controls {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 1rem;
  background: transparent;
  padding: 0;
}

.control-card {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  background: var(--surface-color);
  padding: 1rem;
  border-radius: 0.9rem;
  border: 1px solid #334155;
  box-shadow: 0 10px 25px rgba(0, 0, 0, 0.35);
}

.control-card button {
  width: 100%;
}

label {
  font-size: 0.95rem;
  color: var(--text-muted);
}

button {
  padding: 0.75rem 1rem;
  border-radius: 0.5rem;
  border: none;
  background: var(--primary-color);
  color: #fff;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s;
  box-shadow: 0 4px 6px rgba(37, 99, 235, 0.3);
}

button:hover {
  background: var(--primary-hover);
  transform: translateY(-2px);
  box-shadow: 0 6px 12px rgba(37, 99, 235, 0.4);
}

button:active {
  transform: translateY(0);
}

button.secondary {
  background: transparent;
  border: 1px solid var(--text-muted);
  color: var(--text-color);
  box-shadow: none;
}

button.secondary:hover {
  background: rgba(255, 255, 255, 0.05);
}

.visualization-area {
  background: #020617;
  border-radius: 1rem;
  min-height: 600px;
  position: relative;
  overflow: hidden;
  box-shadow: inset 0 0 50px rgba(0, 0, 0, 0.8);
  display: flex;
  justify-content: center;
  align-items: center;
  perspective: 1000px;
  /* Essential for 3D */
}

#graph-container {
  display: grid;
  gap: 0;
  /* No gap for connected walls */
  transform-style: preserve-3d;
  transform: rotateX(45deg) rotateZ(0deg);
  transition: transform 0.5s;
  padding: 20px;
}

.cell {
  width: 30px;
  height: 30px;
  position: relative;
  transform-style: preserve-3d;
  transition: background-color 0.3s;
  background-color: var(--floor-color);
}

/* 3D Wall Styling */
.cell.wall {
  background-color: var(--wall-color);
  transform: translateZ(15px);
  /* Lift up */
  box-shadow: 0 0 5px rgba(0, 0, 0, 0.5);
}

/* Faces for 3D effect on walls */
.face {
  position: absolute;
  background-color: var(--wall-side);
  display: none;
}

.cell.wall .face {
  display: block;
}

.face.left {
  width: 30px;
  height: 30px;
  transform: rotateY(-90deg) translateZ(15px);
  background-color: #1e293b;
  /* Darker side */
}

.face.right {
  width: 30px;
  height: 30px;
  transform: rotateY(90deg) translateZ(15px);
  background-color: #334155;
}

.face.top {
  width: 30px;
  height: 30px;
  transform: rotateX(90deg) translateZ(15px);
  background-color: #475569;
  /* Top is same as main color usually, but here main is front */
}

/* Special Cells */
.cell.start {
  background-color: var(--start-color);
  box-shadow: 0 0 15px var(--start-color);
  transform: translateZ(2px);
}

.cell.end {
  background-color: var(--end-color);
  box-shadow: 0 0 15px var(--end-color);
  transform: translateZ(2px);
}

.cell.visited {
  background-color: rgba(16, 185, 129, 0.2);
  box-shadow: inset 0 0 10px rgba(16, 185, 129, 0.2);
}

.cell.path {
  background-color: var(--path-color);
  box-shadow: 0 0 15px var(--path-color);
  transform: translateZ(5px);
  z-index: 10;
}

.cell.active {
  background-color: var(--active-color);
  box-shadow: 0 0 20px var(--active-color);
  transform: translateZ(5px);
  z-index: 20;
}

.info-panel {
  background: var(--panel-color);
  padding: 1.25rem;
  border-radius: 1rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
  border: 1px solid #475569;
  box-shadow: 0 10px 20px rgba(0, 0, 0, 0.2);
}

#status-message {
  font-size: 1rem;
  font-weight: 500;
}

#status-message.error {
  color: #ef4444;
}

.legend {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  color: var(--text-muted);
  font-size: 0.95rem;
}

.legend-item {
  display: inline-block;
  width: 18px;
  height: 18px;
  border-radius: 4px;
  margin-right: 4px;
  vertical-align: middle;
}

.legend-item.visited {
  background: var(--visited-color);
}

.legend-item.active {
  background: var(--active-color);
}

.legend-item.path {
  background: var(--path-color);
}

.legend-item.wall {
  background: var(--wall-color);
}

@media (max-width: 900px) {
  .controls {
    grid-template-columns: 1fr;
  }
}