:root {
  --bg-color: #0a0e14;
  --node-root: #ff9800;
  --node-level1: #2196f3;
  --node-level2: #4caf50;
  --node-level3: #9c27b0;
  --node-level4: #e91e63;
  --node-level5: #00bcd4;
  --text-primary: #e8e8e8;
  --text-secondary: #9ca3af;
  --border-color: rgba(255, 255, 255, 0.15);
  --glass-bg: rgba(255, 255, 255, 0.05);
  --glass-border: rgba(255, 255, 255, 0.2);
  --node-bg: #1a1f2e;
  --node-bg-hover: #232938;
  --link-color: rgba(255, 255, 255, 0.2);
  --link-glow: rgba(255, 255, 255, 0.5);
  --control-btn-bg: rgba(0, 0, 0, 0.6);
  --control-btn-hover: rgba(255, 255, 255, 0.15);
  
  /* RGB values for gradient backgrounds */
  --node-root-rgb: 255, 152, 0;
  --node-level1-rgb: 33, 150, 243;
  --node-level2-rgb: 76, 175, 80;
  --node-level3-rgb: 156, 39, 176;
  --node-level4-rgb: 233, 30, 99;
  --node-level5-rgb: 0, 188, 212;
}

[data-theme="light"] {
  --bg-color: #f8fafc;
  --text-primary: #0f172a;
  --text-secondary: #64748b;
  --border-color: rgba(0, 0, 0, 0.15);
  --glass-bg: rgba(0, 0, 0, 0.03);
  --glass-border: rgba(0, 0, 0, 0.2);
  --node-bg: #ffffff;
  --node-bg-hover: #f1f5f9;
  --link-color: rgba(0, 0, 0, 0.15);
  --link-glow: rgba(0, 0, 0, 0.4);
  --control-btn-bg: rgba(255, 255, 255, 0.95);
  --control-btn-hover: rgba(0, 0, 0, 0.08);
}

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

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  background-color: var(--bg-color);
  color: var(--text-primary);
  overflow: hidden;
  height: 100vh;
  width: 100vw;
}

#mindmap-container {
  width: 100vw;
  height: 100vh;
}

.node {
  cursor: pointer;
}

.node circle {
  fill: #fff;
  stroke: steelblue;
  stroke-width: 3px;
}

.node text {
  font-size: 12px;
  fill: var(--text-primary);
}

.link {
  fill: none;
  stroke: var(--link-color);
  stroke-width: 2px;
  transition: stroke-width 0.3s ease, stroke 0.3s ease;
  stroke-linecap: round;
}

.link:hover {
  stroke: var(--link-glow);
  stroke-width: 3px;
}

.link-glow {
  stroke: var(--link-glow);
}

/* Native SVG nodes */
.node {
  cursor: pointer;
  transition: all 0.2s ease;
}

.node-rect {
  fill: var(--node-bg);
  stroke: var(--border-color);
  stroke-width: 1.5px;
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

/* Root node emphasis */
.node-level-0 .node-rect { 
  stroke: var(--node-root);
  stroke-width: 2px;
}

/* Level colors */
.node-level-1 .node-rect { stroke: var(--node-level1); }
.node-level-2 .node-rect { stroke: var(--node-level2); }
.node-level-3 .node-rect { stroke: var(--node-level3); }
.node-level-4 .node-rect { stroke: var(--node-level4); }
.node-level-5 .node-rect { stroke: var(--node-level5); }

/* Hover feedback */
.node:hover .node-rect {
  stroke-width: 2.5px;
  filter: brightness(1.1);
}

.node-level-0:hover .node-rect { box-shadow: 0 0 20px rgba(var(--node-root-rgb), 0.4); }
.node-level-1:hover .node-rect { box-shadow: 0 0 20px rgba(var(--node-level1-rgb), 0.3); }
.node-level-2:hover .node-rect { box-shadow: 0 0 20px rgba(var(--node-level2-rgb), 0.3); }
.node-level-3:hover .node-rect { box-shadow: 0 0 20px rgba(var(--node-level3-rgb), 0.3); }
.node-level-4:hover .node-rect { box-shadow: 0 0 20px rgba(var(--node-level4-rgb), 0.3); }
.node-level-5:hover .node-rect { box-shadow: 0 0 20px rgba(var(--node-level5-rgb), 0.3); }

/* Expandable indicator */
.node-expandable-outline {
  pointer-events: none;
  transition: all 0.3s ease;
  animation: pulse-outline 2.5s ease-in-out infinite;
}

@keyframes pulse-outline {
  0%, 100% { opacity: 0.3; stroke-width: 1.5px; }
  50% { opacity: 0.6; stroke-width: 2px; }
}

.node-level-0 .node-expandable-outline { stroke: var(--node-root); }
.node-level-1 .node-expandable-outline { stroke: var(--node-level1); }
.node-level-2 .node-expandable-outline { stroke: var(--node-level2); }
.node-level-3 .node-expandable-outline { stroke: var(--node-level3); }
.node-level-4 .node-expandable-outline { stroke: var(--node-level4); }
.node-level-5 .node-expandable-outline { stroke: var(--node-level5); }

.node-collapsed:hover .node-expandable-outline {
  opacity: 1 !important;
  stroke-width: 2.5px;
  animation: none;
}

/* Typography */
.node-text {
  fill: var(--text-primary);
  font-size: 13px;
  font-weight: 500;
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  pointer-events: none;
  user-select: none;
}

.node-level-0 .node-text { font-size: 16px; font-weight: 600; }
.node-level-1 .node-text { font-size: 14px; }

/* Links */
.link {
  fill: none;
  stroke: var(--link-color);
  stroke-width: 1.5px;
  stroke-linecap: round;
  opacity: 0.6;
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.link:hover {
  stroke: var(--link-glow);
  stroke-width: 2.5px;
  opacity: 1;
}
.node-card {
  background: var(--node-bg);
  border: 1px solid var(--border-color);
  border-radius: 24px;
  padding: 12px 20px;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.4);
  width: 220px;
  height: 100%;
  transition: transform 0.3s ease, border-color 0.3s ease, box-shadow 0.3s ease, background 0.3s ease;
  contain: layout style paint;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  user-select: none;
  min-height: 48px;
  font-size: 11px;
  font-weight: 500;
  line-height: 1.4;
  color: var(--text-primary);
  position: relative;
  word-wrap: break-word;
  overflow-wrap: break-word;
  hyphens: auto;
  z-index: 10;
}

.node-card:hover {
  transform: scale(1.05);
  border-color: var(--border-color);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.5);
  background: var(--node-bg-hover);
  will-change: transform;
}

/* Base level styling - DRY approach */
.node-level-0 .node-card { border-left-color: var(--node-root); --grad-rgb: var(--node-root-rgb); }
.node-level-1 .node-card { border-left-color: var(--node-level1); --grad-rgb: var(--node-level1-rgb); }
.node-level-2 .node-card { border-left-color: var(--node-level2); --grad-rgb: var(--node-level2-rgb); }
.node-level-3 .node-card { border-left-color: var(--node-level3); --grad-rgb: var(--node-level3-rgb); }
.node-level-4 .node-card { border-left-color: var(--node-level4); --grad-rgb: var(--node-level4-rgb); }
.node-level-5 .node-card { border-left-color: var(--node-level5); --grad-rgb: var(--node-level5-rgb); }

/* Shared gradient using CSS variable */
.node-level-0 .node-card,
.node-level-1 .node-card,
.node-level-2 .node-card,
.node-level-3 .node-card,
.node-level-4 .node-card,
.node-level-5 .node-card {
  border-left: 5px solid;
  background: linear-gradient(90deg, rgba(var(--grad-rgb), 0.2) 0%, var(--bg-color) 20%);
}

/* Indicating collapsed state */
.node-collapsed .node-card {
  box-shadow: 0 0 15px rgba(255, 255, 255, 0.08);
  padding-right: 48px;
  /* Extra space for the indicator */
}

.node-collapsed .node-card::after {
  content: '+';
  position: absolute;
  right: 12px;
  top: 50%;
  transform: translateY(-50%);
  width: 20px;
  height: 20px;
  background: var(--glass-bg);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 12px;
  color: var(--text-primary);
  opacity: 0.9;
  border: 1px solid var(--glass-border);
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
}

.controls {
  position: fixed;
  bottom: 20px;
  right: 20px;
  display: flex;
  gap: 10px;
  z-index: 100;
  align-items: center;
}

.search-wrapper {
  position: relative;
  display: flex;
  align-items: center;
}

.search-input {
  background: var(--control-btn-bg);
  border: 1px solid var(--glass-border);
  color: var(--text-primary);
  padding: 8px 36px 8px 12px;
  border-radius: 8px;
  font-size: 13px;
  width: 200px;
  transition: background 0.2s, border-color 0.2s, width 0.3s;
  backdrop-filter: blur(10px);
}

.search-input:focus {
  outline: none;
  border-color: var(--node-level1);
  background: var(--control-btn-hover);
  width: 250px;
}

.search-input::placeholder {
  color: var(--text-secondary);
}

.search-clear {
  position: absolute;
  right: 8px;
  background: transparent;
  border: none;
  color: var(--text-secondary);
  font-size: 16px;
  cursor: pointer;
  padding: 4px 8px;
  border-radius: 4px;
  transition: background 0.2s, color 0.2s;
  display: flex;
  align-items: center;
  justify-content: center;
}

.search-clear:hover {
  background: var(--control-btn-hover);
  color: var(--text-primary);
}

.control-btn {
  background: var(--control-btn-bg);
  border: 1px solid var(--glass-border);
  color: var(--text-primary);
  padding: 8px 12px;
  border-radius: 8px;
  cursor: pointer;
  transition: background 0.2s;
  backdrop-filter: blur(10px);
}

.control-btn:hover {
  background: var(--control-btn-hover);
}

/* Search */
.search-match .node-rect {
  stroke: #fbbf24 !important;
  stroke-width: 3px !important;
  fill: rgba(251, 191, 36, 0.1);
}

.node.search-match {
  animation: pulse-glow 1.5s ease-in-out infinite;
}

.search-dimmed {
  opacity: 0.3;
  transition: opacity 0.4s ease;
}

@keyframes pulse-glow {
  0%, 100% { filter: drop-shadow(0 0 10px rgba(251, 191, 36, 0.5)); }
  50% { filter: drop-shadow(0 0 20px rgba(251, 191, 36, 0.8)); }
}

/* Responsive */
@media (max-width: 768px) {
  .node-text { font-size: 11px; }
  .node-level-0 .node-text { font-size: 14px; }
  .node-level-1 .node-text { font-size: 12px; }
}