I would like to customize the form to some extent

Hi there

I refer to the following article.

Customize Your Form Using Custom CSS Codes

https://www.jotform.com/help/75-Customize-Your-Form-Using-Custom-CSS-Codes

Customizing the form is required to understand the only CSS?

What about another code such as HTML?

I will wait for your advice.

Thank you for contacting us. 

The css code injected to a form changes the form styles such as color, position of the field, alignment, etc. I'm not sure what you are referring with HTML customisation but if you want to make some changes on your form which is actually not possible on the JotForm, you may consider to embed your form to your website (if you have one) with form's source code and then make changes on the source code. 

On the other hand, if you tell us what changes you want to do on your form, we can try to find you a solution. 

@Rose

Thank you for your reply.

What I am looking for is something like as follows.

CSS Forms

https://www.w3schools.com/css/css_form.asp.

My guess is that we forget about HTML.

As far as HTML is concerned, your user guide never takes an article.

If you have any comments, let me know by your return message.

In fact you do not need to add a css code to your form to accomplish the thing you want to do. You can create the same form with our basic form elements. 

Name field: We have a specific field called "Full Name" for this field where the First Name and Last Name field is side by side. 

If you want to separate First Name and Last Name to different lines, you may also consider to use "Short Text Entry" field. It is a simple Textbox field. 

For the Country, you can either add a "Dropdown" field or "Address" field. If you want to use a "Dropdown" field, you need to add the country to the field options:

If you want to use "Address" field to show only Country option, you need to disable the other address field option on the field properties as you can see here:

With Address field, you do not need to add Country options one by one. When you preview your form, all the countries will appears once you click to address field.

I hope, these help you. If you need any further assistance by our side, please let us know.