Hi,

The CSS codes you can use, are provided below: 

First question: 

I change paddings top and bottom in Name and Mail fields, but it works only on mobile - I set 14px. 

#wpdcom input#wc_email-0_0.wc_email.wpd-field{
    padding-top:  20px;
    padding-bottom:  20px;
}
#wpdcom input#wc_name-0_0.wc_name.wpd-field{
   padding-top: 20px;
   padding-bottom: 20px;
}

 Second question:

 I don't know how to change colour buttons in toolkit, I can't wind it in css.

.ql-snow.ql-toolbar button {
    color:  #9f1414 !important;
}
#wpdcom .ql-toolbar button .ql-stroke{
    color: #9f1414 !important;
    stroke: #9f1414 !important;

}
#wpdcom .ql-toolbar button .ql-fill, #wpdcom .ql-toolbar button .ql-fill {
    color:  #9f1414  !important;
    fill: #9f1414  !important;
}

Put the code in the "Custom CSS code" textarea, located in the Dashboard > wpDiscuz > Settings > Styles & Colors admin page.

The red-marked values can be changed as you like.

Don't forget to delete the caches before checking.

Perfect, all is done! Thank you very much for help.

Last question, my guests can vote using voting button only for admin comments, not for other guests comments. In options I allowed guests on voting on comments. Colud you tell me how to solve this?

Thanks