How can I, using css, set the check boxes in my form to be unchecked?

I'm not sure why but in my form all of the check boxes are checked by default. When I look in the check box properties all the check boxes do not have the "checked" property active. I think I need to use css to disable the automated checking that the checkboxes are doing. What is the code to set all of a form's check boxes to unchecked? 

I have tested your form and I saw that all check box options are selected. After that I have cloned your form and i saw that each check box field is separate field and that you have a lot of CSS for position of your form fields. Your check box options are pre-selected, because they do not have option. All options for your check box field are empty.

To resolve your issue you will need to add some options to each of your check box fields. For example you can add only one character. 

Considering that fields inside of Form Builder are overlapping because of the CSS code you added, I had to remove all CSS code and then I have added option for each check box field. After that I have re added CSS code that I previously removed. Option that I added are not visible on the form, because image fileds are over them, so your users will not be able to see them. 

My cloned form now looks like this.

Here is my cloned form: https://form.jotform.com/62092003098955 

Feel free to clone it.

Hope this will help. Let us know if you need further assistance.