两个属性问题

1. 建议统一 `content` 和 `text`。也许是 text 支持自定义格式文本而 button 只支持普通文本？
2. 百分比数值是怎么计算的？`x = 50%` 默认基于可视区域宽度，那么 `fontSize = 10%` 呢？宽度？高度？（绝对值）pt？em？

Start with the issue body’s questions about content, text, button, fontSize, and percentage values. Determine the intended attribute semantics and reference dimensions, then confirm the expected behavior and document a decided scope before identifying implementation files or tests.

Written by the indexing model from the issue text.