RE: How do you remove the cell borders in a Grid?

.yourgrid .v-grid-cell {
border: none !important;
}
this should be work.

I would like to remove the border around all the cells in a Grid. I don’t believe it’s possible to do with code, and the css for Table doesn’t apply to Grid, therefore how do you do this for Grid?

That worked great! Any idea how to also remove the border on the outside of the grid too?

You may try this;

.yourgrid .v-grid-tablewrapper{
border: none
}

The best way to modify Grid’s styling is by overriding the Sass variables defined in the Valo theme. For instance, to remove the all the borders, one would add $v-grid-border: none to the custom theme that overrides Valo. You can find all variables used in the [_grid.scss]
(https://github.com/vaadin/framework/blob/2c3df1adfdecdda7747ec63b00ab4a6c5e1315d3/themes/src/main/themes/VAADIN/themes/valo/components/_grid.scss#L3-L64) file. Find more info on how to use variables in the [documentation]
(https://vaadin.com/docs/v8/framework/themes/themes-valo.html).