/* CSS for drawing ym "polar reverse Collatz graph"
 */
body {
            margin: 0;
            display: flex;
            font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
            height: 100vh;
            overflow: hidden;
            background: #f4f5f7;
        }
        #sidebar {
            width: 320px;
            padding: 20px;
            background: #ffffff;
            border-right: 1px solid #e0e0e0;
            box-shadow: 2px 0 8px rgba(0,0,0,0.05);
            z-index: 10;
            overflow-y: auto;
        }
        h2 {
            margin-top: 0;
            font-size: 1.2rem;
            color: #333;
        }
        p.desc {
            font-size: 0.85rem;
            color: #666;
            margin-bottom: 20px;
        }
        #main {
            flex: 1;
            overflow: auto;
            position: relative;
            background: #fafafa;
        }
        .control-group {
            margin-bottom: 15px;
        }
        label {
            display: block;
            margin-bottom: 6px;
            font-weight: 600;
            font-size: 0.85rem;
            color: #444;
        }
        input[type="number"], input[type="color"] {
            /*width: 100%;
            padding: 8px;*/
            border: 1px solid #ccc;
            border-radius: 4px;
            box-sizing: border-box;
            font-size: 0.9rem;
        }
        .checkbox-group {
            display: flex;
            align-items: center;
            font-weight: 600;
            font-size: 0.85rem;
            color: #444;
            cursor: pointer;
        }
        .checkbox-group input {
            transform: scale(1.2);
            margin-right: 10px;
            cursor: pointer;
        }
        button {
            padding: 12px 15px;
            background: #2196F3;
            color: white;
            border: none;
            border-radius: 4px;
            cursor: pointer;
            font-size: 0.95rem;
            font-weight: bold;
            /*width: 100%;*/
            transition: background 0.2s;
            margin-top: 10px;
        }
        button:hover {
            background: #1976D2;
        }
        svg {
            display: block;
            margin: 0 auto;
        }
        .node-circle {
            fill: #ffffff;
            stroke: #333333;
        }
        .node-text {
            font-family: monospace;
            text-anchor: middle;
            dominant-baseline: central;
            pointer-events: none;
        }
        /* Styling for multiples of 3 */
        .node-mult-3 .node-circle {
            fill: #fff3e0;
            stroke: #ff9800;
        }
        .node-mult-3 .node-text {
            fill: #e65100;
            font-weight: bold;
        }
        .edge-straight {
            fill: none;
        }
        .edge-arc {
            fill: none;
        }