feat(display): add chairman speech page and refine layouts

This commit introduces a new page for the Chairman of the Board's speech and includes several visual refinements for the
event display.

- Add `speech/3.html` to display the chairman's video.
- Update the committee member list.
- Adjust font sizes, colors, and element positioning on the main and committee list pages for better visual
presentation.
- Fine-tune background video placement and scaling.

20251012/commitee-list/commitee.js

@@ -28,7 +28,6 @@ const members = [
   "张祥明",
   "黄升文",
   "陈照明",
-  "赵汶德",
   "陈世勇",
   "王畯杰",
   "黄伟宏",