Checkbox styling in style.css needed

Hi there,

I finally got the plugin to work and I really enjoy it.
I already have the following code in my style.css to make checkboxes smaller than normal:

/* Styling CF7 Checkbox */
span.wpcf7-list-item {
display: block;
font-size: 13px;
}

Unfortunately it doesn‘t affect the mailpoetsignup-checkbox. What code do I have to apply there?
Also the text literally is attached at the textbox, there is no spacing.

Thank you for helping!