How to style this form with css?

Question

Layout

Please help me write css to make it look nice.
I couldn’t find ready-made non-ugly options on the Internet, there’s even nothing to take for the base.
In my case, there will be 1 field, a phone number and a send button.
Here is the skeleton.

<form class="form-wrapper cf">
[tel* tel-181 placeholder "Ваш номер телефона"]
[submit "Звонок!"]	
</form>

Answer 1

https://codepen.io/meylisday/pen/LQJmaW