Change the Design..

The design is normally taken over from the theme you are using. So the textfield and button should look like the rest of your page.
Or do you exactly want to have the design shown in your screenshot?

If there is a possibility to get exactly the design then I would not say no ??

In that case you need to style the textfield and button via CSS. Just to give you an idea:

#dc-domain-1 {
	height: 75px;
	margin-right: 0;
	border-bottom-left-radius: 50px;
	border-top-left-radius: 50px;
}
#dc-submit-1 {
	height: 75px;
	background-color: orange;
	border-bottom-right-radius: 50px;
	border-top-right-radius: 50px;
}

The CSS needs to modified depending on the theme you are using.

We are on the right track, not perfect but I think that at this point we can test a little ourselves ?? https://ibb.co/9tzFVpG

Have a nice weekend.

Hi, can you help me to get css additional for the design and the drop down like this?

Really appreciate it

https://ibb.co/S311sn3

Thank you

That depends on the theme you are using. In principle, that should be possible.
You can find the HTML and CSS structure here: https://wp24.org/images/plugins/domain-check/html-css-structure.png

Thank you for your fast response.
I really appreciate it.

Anyway, I tried but nothing happen.
I check for my project:

https://www.weappsyou.com

if you could help to check and help me.

to get this kind of dropdown.

https://ibb.co/S311sn3

thank you for your help. really appreciate it.

I don’t know what you exactly mean with dropdown. But since you are using an other theme it’s difficult to change the design to your example.
You could use a button instead of links, to do so change the WooCommerce settings from “[link]buy now[/link] for [price]” to “[button]buy now[/button] for [price]”.
For other stylings you would need to put custom CSS, e.g. to add a gray line do:

.wp24-dc .table-cell {
  border-bottom: 1px solid lightgray;
}

Hi, thank you for your response.

I also wonder how to make the proportions between domain name and TLDs on the website.
Because, I share the picture, the proportions is to heavy on domain area, but not on TLDs.

https://ibb.co/k9806N8

Thank you so much, really appreciate it.

You can change the width of the domain name field in the general settings.