Looks very good, it’s almost great, some small issues tho I’ll tell. And will give you some suggestions.
Layout is responsive, but one boi in your page could break your design very easy and it’s textarea.
About the colour scheme, it’s a design and opinion thing, but I would select another colour instead of green over red, or vice versa. but this is just a suggestion, you may reject.
You set cols for controlling the textarea width which is not recommended, please don’t. Use css instead. cols forces the browser apply constant absolute value as width for textarea. This is true 25 is not too much, but try to control visual stuffs with css, this cols form is kind of retro.
Placeholder for text fields, labels for input elements, default disable option for combobox, good spacing between elements, and good shrp submit button. very great I liked, perfect.
I explained the reason why you should not use cols for textarea, or generally any absolute unit for sizing(either with css, or html) in my survey form challenge walkthrough post for more explination if you interested. Same notes some suggestions about the design and work.
Keep going on great work, happy programming.