I solved it like this:
function onEdit(e) {
if (e) {
var ss = e.source.getActiveSheet();
var r = e.source.getActiveRange();
if (r.getRow() != 1 && ss.getName() == "Sheet1") {
// Status in column 6 (F)
status = ss.getRange(r.getRow(), 6).getValue();
// Range to put background color to (rowStart, numberOfRows, columnStart, numberOfColumns)
rowRange = ss.getRange(r.getRow(),1,1,6);
if (status == 'Plan') {
rowRange.setBackgroundColor("white");
} else if (status == 'Offer') {
rowRange.setBackgroundColor("yellow");
} else if (status == 'Confirmed') {
rowRange.setBackgroundColor("green");
} else if (status == 'Canceled') {
rowRange.setBackgroundColor("red");
} else if (status == '') {
rowRange.setBackgroundColor("white");
}
}
}
}