sets the right and left padding (applies the specified value to both sides)
webix.ui({
view:"gridlayout",
gridColumns:4, gridRows:3,
paddingX:20,
cells:[
{ template:"Single", x:0, y:0, dx:1, dy:1 },
{ template:"Wide 1", x:1, y:0, dx:2, dy:1 },
// more cells
]
});