f0'] },
                { name: '海王星', radius: 12, colors: ['#647ba5', '#7595bf', '#4e5d73', '#789ebf'] },
                { name: '冥王星', radius: 5, colors: ['#d8cbbb', '#f4ebdc', '#402a16', '#a79f97'] }
            ];

            // 2. 公转周期（地球日）→ 真实秒: 日/10
            const periodDays = [0, 88, 225, 365, 687, 4333, 10759, 30687, 60190, 90560];
            const speeds = periodDays.map(d => d === 0 ? 0 : 2 * Math.PI / (d / 10)); // rad/s

            let radii = []; 