body {
            margin: 0;
            overflow: hidden;
            background-color: #e0e0e0;
            background-size: cover;
            background-position: center;
            background-repeat: no-repeat;
            font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
            transition: background-color 0.2s;
        }

        canvas {
            display: block;
            cursor: none; /* Hide default cursor */
        }

        /* --- UI Controls --- */

        /* Open Button (Visible by default) */
        #openControls {
            position: absolute;
            bottom: 20px;
            right: 20px;
            padding: 10px 20px;
            background: rgba(255, 255, 255, 0.9);
            border: 1px solid rgba(0,0,0,0.1);
            border-radius: 8px;
            cursor: pointer;
            font-weight: 600;
            color: #333;
            box-shadow: 0 4px 10px rgba(0,0,0,0.1);
            transition: transform 0.2s, background 0.2s;
            z-index: 100;
        }

        #openControls:hover {
            transform: translateY(-2px);
            background: #fff;
        }

        /* Panel Container (Hidden by default) */
        #controls {
            display: none; /* Default hidden */
            position: absolute;
            bottom: 20px;
            right: 20px;
            width: 340px;
            max-height: 85vh;
            overflow-y: auto;
            background: rgba(255, 255, 255, 0.95);
            padding: 20px;
            border-radius: 12px;
            box-shadow: 0 10px 40px rgba(0,0,0,0.25);
            backdrop-filter: blur(12px);
            user-select: none;
            border: 1px solid rgba(255,255,255,0.6);
            z-index: 101;
            animation: slideIn 0.3s ease-out;
        }

        @keyframes slideIn {
            from { opacity: 0; transform: translateY(20px); }
            to { opacity: 1; transform: translateY(0); }
        }

        /* Header with Hide button */
        .panel-header {
            display: flex;
            justify-content: space-between;
            align-items: center;
            margin-bottom: 15px;
            border-bottom: 1px solid #eee;
            padding-bottom: 10px;
        }

        h3 {
            margin: 0;
            font-size: 16px;
            text-transform: uppercase;
            letter-spacing: 1px;
            color: #111;
        }

        #closeControls {
            background: #f0f0f0;
            border: none;
            padding: 5px 12px;
            border-radius: 4px;
            cursor: pointer;
            font-size: 12px;
            font-weight: bold;
            color: #555;
            transition: background 0.2s;
        }
        #closeControls:hover {
            background: #ddd;
            color: #000;
        }

        /* Scrollbar */
        #controls::-webkit-scrollbar { width: 6px; }
        #controls::-webkit-scrollbar-thumb { background-color: #ccc; border-radius: 3px; }

        /* Controls Layout */
        .control-group {
            margin-bottom: 15px;
            display: flex;
            flex-direction: column;
        }
        
        .color-row {
            display: flex;
            justify-content: space-between;
            gap: 10px;
            margin-bottom: 15px;
        }
        .color-item { flex: 1; }

        label {
            display: flex;
            justify-content: space-between;
            font-size: 13px;
            margin-bottom: 5px;
            font-weight: 600;
            color: #333;
        }

        input[type="range"] {
            width: 100%;
            cursor: pointer;
            height: 6px;
            background: #ddd;
            border-radius: 3px;
            appearance: none;
        }
        input[type="range"]::-webkit-slider-thumb {
            appearance: none;
            width: 16px;
            height: 16px;
            background: #444;
            border-radius: 50%;
            cursor: pointer;
            transition: background 0.2s;
        }
        input[type="range"]::-webkit-slider-thumb:hover { background: #000; }

        input[type="file"] {
            font-size: 11px;
            width: 100%;
            color: #555;
        }

        input[type="color"] {
            width: 100%;
            height: 30px;
            border: 1px solid #ddd;
            border-radius: 4px;
            cursor: pointer;
            background: none;
            padding: 2px;
        }

        .divider {
            height: 1px;
            background: #eee;
            margin: 15px 0;
        }