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

body {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  background: #291D35;
  margin: 0;
  min-height: 100vh;
  overflow: hidden;
}

.container {
  width: 100vw;
  height: 100vh;
  position: relative;
}

svg#concept-svg {
  width: 100vw;
  height: 100vh;
  display: block;
  position: absolute;
  top: 0;
  left: 0;
  z-index: 1;
}

.link {
  stroke-width: 1;
  opacity: 0.85;
  transition: opacity 0.3s;
}
.link.dimmed {
  opacity: 0.15;
}
.link.highlighted {
  opacity: 1;
  stroke-width: 7;
}

.node-group {
  cursor: pointer;
}

.node-circle {
  /* No stroke, no border */
  filter: drop-shadow(0 2px 12px rgba(180, 120, 200, 0.10));
  transition: filter 0.3s, opacity 0.3s;
}
.node-circle.selected {
  stroke: #f4a79c;
  stroke-width: 5px;
  filter: drop-shadow(0 4px 32px #f4a79c44);
}
.node-circle.neighbor {
  stroke: #dac4e9;
  stroke-width: 4px;
}
.node-circle.dimmed {
  opacity: 0.25;
}

.node-label {
  font-size: 0.95rem;
  font-weight: 500;
  fill: #fff;
  pointer-events: none;
  text-anchor: middle;
  alignment-baseline: middle;
  user-select: none;
}

.legend {
    position: absolute;
    bottom: 20px;
    right: 20px;
    background: rgba(255,255,255,0.1);
    backdrop-filter: blur(10px);
    border-radius: 10px;
    padding: 15px;
    border: 1px solid rgba(255,255,255,0.2);
    z-index: 10;
}

.legend-item {
    display: flex;
    align-items: center;
    margin-bottom: 8px;
    color: white;
    font-size: 0.9rem;
}

.legend-item:last-child {
    margin-bottom: 0;
}

.legend-item .line {
    width: 40px;
    height: 2px;
    margin-right: 10px;
    background: rgba(255,255,255,0.8);
}
.legend-item .line.dashed {
    background: none;
    border-top: 2px dashed rgba(255,255,255,0.8);
}
.legend-item .line.arrowed {
    background: none;
    border-top: 1.5px solid rgba(255,255,255,0.8);
    position: relative;
}
.legend-item .line.arrowed::after {
    content: '';
    position: absolute;
    right: -5px;
    top: -3px;
    width: 0;
    height: 0;
    border-left: 5px solid rgba(255,255,255,0.8);
    border-top: 3px solid transparent;
    border-bottom: 3px solid transparent;
}

/* SVG definitions for arrow markers */
svg {
    position: absolute;
    width: 0;
    height: 0;
    overflow: hidden;
}

#arrowhead {
    fill: rgba(255,255,255,0.7);
}