:root {
  --bg: #0a192f;
  --panel: rgba(15, 20, 40, 0.95);
  --accent: #4facfe;
  --accent-bright: #00f2fe;
  --text: #ccd6f6;
  --muted: #8892b0;
}

* { margin: 0; padding: 0; box-sizing: border-box; }
  body {
    font-family: 'Segoe UI', sans-serif;
    background: var(--bg);
    color: #fff;
    overflow: hidden;
    height: 100vh;
  }
  #canvas-container { position: absolute; top: 0; left: 0; width: 100%; height: 100%; }
  
  .panel {
    position: absolute;
    background: var(--panel);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(79, 172, 254, 0.3);
    border-radius: 12px;
    padding: 16px;
    box-shadow: 0 8px 32px rgba(0,0,0,0.4);
    z-index: 100;
  }
  
  #header { top: 20px; left: 20px; max-width: 280px; }
  #header h1 {
    font-size: 20px;
    background: linear-gradient(90deg, #4facfe, #00f2fe);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
  }
  #header .sub { font-size: 11px; color: var(--muted); letter-spacing: 2px; }
  #header .info { margin-top: 10px; font-size: 11px; color: var(--text); line-height: 1.6; }
  #header .info strong { color: var(--accent); }
  
  #controls { top: 20px; right: 20px; width: 240px; }
  #controls h3 { font-size: 12px; color: var(--accent); margin-bottom: 10px; letter-spacing: 1px; }
  
  .btn {
    display: block;
    width: 100%;
    padding: 8px 12px;
    margin-bottom: 5px;
    background: rgba(255,255,255,0.05);
    border: 1px solid rgba(255,255,255,0.1);
    color: var(--text);
    border-radius: 6px;
    cursor: pointer;
    font-size: 11px;
    text-align: left;
    transition: all 0.3s;
  }
  .btn:hover { background: rgba(79, 172, 254, 0.2); border-color: var(--accent); }
  .btn.active { background: linear-gradient(90deg, #4facfe, #00f2fe); color: #0a192f; font-weight: 600; }
  .btn span { float: right; opacity: 0.7; font-size: 10px; }
  
  #info { bottom: 20px; left: 20px; max-width: 380px; }
  #info h4 { color: var(--accent); font-size: 12px; margin-bottom: 8px; }
  #info p { font-size: 11px; color: var(--text); line-height: 1.6; }
  
  #legend { bottom: 20px; right: 20px; }
  #legend h4 { color: var(--accent); font-size: 12px; margin-bottom: 8px; }
  .legend-item { display: flex; align-items: center; margin-bottom: 4px; font-size: 10px; color: var(--text); }
  .legend-color { width: 12px; height: 12px; border-radius: 2px; margin-right: 6px; border: 1px solid rgba(255,255,255,0.2); }
  
  #loading {
    position: absolute; top: 50%; left: 50%;
    transform: translate(-50%, -50%);
    text-align: center; color: var(--accent); z-index: 1000;
  }
  .spinner {
    width: 50px; height: 50px;
    border: 3px solid rgba(79, 172, 254, 0.2);
    border-top-color: var(--accent);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin: 0 auto 15px;
  }
  @keyframes spin { to { transform: rotate(360deg); } }
  .hidden { display: none !important; }
.controls-section-title { margin-top: 12px; }