         // 颜色候选集（由浅到深）
            const colors = [
                '#eaf4fc', '#eaedf7', '#e8ecef', '#ebf6f7', '#bbc8e6',
                '#bbbcde', '#8491c3', '#867ba9', '#68699b', '#706caa',
                '#5654a2', '#4d4398', '#4a488e', '#274a78', '#2a4073',
                '#223a70', '#192f60', '#1c305c', '#17184b', '#0f2350'
            ];

            // 曼德博集参数
            let centerX = -0.75, centerY = 0.0;
            let scale = 3.0 / Math.max(window.innerWidth