Truncated circle for the last value

Hello,
first things first: thanks for this awesome library!
I'm having an issue and I can't figure out why.
The circle that focus on the last value of the x axis is truncated. (In the image you can see what I'm talking about)

I think I've tried everything from padding to width and I can't figure out the problem. For the other value there is no problem at all, it looks like "the canvas" of the chart end on that part of the circle.
I'm using twitter Bootstrap at this is the code for the chart:

```
var chart = c3.generate({
bindto: "#grafTempDash",
data: {
x: 'x',
xFormat: '%Y-%m-%d %H:%M', // 'xFormat' can be used as custom format of 'x'
columns: [
a,

b

],
colors: {
'Temperatura Esterna': '#E7443A',

},
},
legend: {
position: 'inset',
inset: {
anchor: 'bottom-left',
x: -10,
y: 0,
background: 0,

}
},
axis: {
y: {
padding: {bottom: 0},
min: minDomain,
tick: {
outer: false
},

label: { // ADD
text: 'Temperatura °C',
position: 'outer-right'

}
},
x: {
type: 'timeseries',
tick: {
format: '%H:%M',
values: e,
outer: false
}
}
}
});

```