feat: Add CSS layout exercises and corresponding HTML files

- Created multiple exercises under the CSS layout section, including:
  - Final page layout with CSS styles and HTML structure.
  - Display and flow concepts with examples of block, inline, and none display types.
  - Selectors and pseudo-classes with practical examples.
  - Overflow and sizing handling in CSS.
  - Grid layout basics for two-dimensional layouts.
  - Fixed and sticky positioning examples.
  - Centering techniques for common layout scenarios.

- Added README files for each exercise to outline objectives and file structures.
- Updated main README to include new sections and usage instructions.

01-html-structure/08-advanced-form-controls/README.md

@@ -0,0 +1,28 @@
+# 练习 8：进阶表单控件
+
+## 目标
+
+补齐常见表单控件的结构写法。
+
+## 你要练什么
+
+- `select`
+- `option`
+- `input type="radio"`
+- `input type="checkbox"`
+- `label`
+
+## 任务
+
+完成一个“学习偏好登记表”，要求包含：
+
+- 姓名输入框
+- 学习方向下拉框
+- 学习节奏单选
+- 感兴趣模块多选
+- 提交按钮
+
+## 文件
+
+- [starter.html](/Volumes/Macintosh HD 1/home/front-end-example/01-html-structure/08-advanced-form-controls/starter.html)
+- [answer.html](/Volumes/Macintosh HD 1/home/front-end-example/01-html-structure/08-advanced-form-controls/answer.html)