Just checked your work, and as I check the layout first, I found ir faulty and broken for tablet size screen, please check:
Same for mobile, when screen goes small (considering a 5" screen), please check:
Label for age text field is broke, same for the combobox. please fix.
radio and checkbox buttons come with associated label tag, very good.
You set placeholder for textfield, textarea and a default disabled option for combobox, very good.
I suggest you select light background colour for your form.
I think if you fix the layout, it’s all perfect.
You may also have a quick read over this survey form challenge walkthrough article which comes with some explanation, tip and code samples could help you fix the layout much better and easier.
keep working on great work, happy programming.