3 Widget Footer and space between

Hi !!!

I try to use between the widgets a space of 10px here
But dont work.
Need a little help i want like that.

I use Simple Css with this.

/* Espace entre menu et content */
.home .entry-content {
margin-top: -26px;
}
.inside-footer-widgets .inner-padding {
padding: 0 0px;
}
.widget {
margin-top: -165px;
}

Thanks.