anychart.onDocumentReady(function () {
var chart = anychart.area();
var series = chart.splineArea([
{x: 'January', value: 125},
{x: 'February', value: -132},
{x: 'March', value: 141},
{x: 'April', value: -158},
series.negativeStroke({color: '#F44336', thickness: 3, dash: '5 5', lineCap: 'round'});
chart.title('Set negative stroke parameter as an object');
chart.container('container');