Adjust left panel styling

User feedback says that the map needs more space / prominence. We could reduce the width of the panel and the text size. Some uncertainty whether the main tool buttons the user switches between should stay the current size or also shrink. Relatedly, one of the design principles I've learned in NPW has me noticing the lack of padding in the left panel generally -- a bit could help.

在前端代码中查找左侧面板的样式，可能位于 CSS 或 Rust UI 文件中。确定当前的宽度、文本大小和内边距值。在考虑主要工具按钮大小的同时，尝试减小面板宽度和文本大小，并添加内边距。在浏览器中测试更改，以查看其对地图突出程度和整体布局的影响。

由索引模型根据 Issue 内容生成。