Make Panels float: left; in CSSLayout?

I have a CSSLayout with some Panels inside:

public class RandomizerPanels extends CssLayout{
        Panel pmenu = new Panel();
        Panel pslider = new Panel();
        Panel pcboBox = new Panel();
        Panel psubmit = new Panel();
        Panel pGrid = new Panel();
        Panel pgridButtons = new Panel();

        addComponent(pmenu);
        pmenu.setStyleName("floats");
        pmenu.setWidth("15%");
        addComponent(pmenu);

        pslider.setWidth("15%");
        pslider.setHeight("150px");
        addComponent(pslider);

        pcboBox.setWidth("45%");
        pcboBox.setHeight("150px");
        addComponent(pcboBox);

        psubmit.setHeight("150px");
        psubmit.setWidth("25%");
        addComponent(psubmit);

        addComponent(pGrid);
        prandomizerGrid.setWidth("85%");

        addComponent(pgridButtons);
        pgridButtons.setWidth("85%");

}

However when I try to edit the CSS in mytheme.scss:

.v-panel.v-widget.floats.v-panel-floats.v-has-width{
    float: left !important;
  }

Nothing happens

If I mess around in Firebug, it will only Float: left; if I put it under Element.style, but I can't figure out how to edit that in vaadin

.