Variable Font Button Set

Create a button set that demonstrates variable font weight animation. Use three text-only buttons arranged horizontally on a light background. Each button label should animate from font-weight 300 to 700 on hover, with a smooth 250ms transition. Add a thin underline that grows from 0% to 100% width on hover. Use a modern variable font (e.g., Inter or any sans-serif variable font fallback). Typography should be the hero—no filled backgrounds, no borders, no icons. Use Tailwind CSS and arbitrary font-weight values.

创建一组展示可变字重动画的按钮。在浅色背景上水平排列三个纯文字按钮。每个按钮标签在悬停时应从字重 300 动画过渡到 700，过渡平滑 250ms。添加一条细下划线，悬停时从 0% 增长到 100% 宽度。使用现代可变字体（如 Inter 或任意无衬线可变字体回退）。字体是主角——无填充背景、无边框、无图标。使用 Tailwind CSS 和任意字重值。