this.title_div_.style.textAlign = 'center';
this.title_div_.style.fontSize = (g.getOption('titleHeight') - 8) + 'px';
this.title_div_.style.fontWeight = 'bold';
+ this.title_div_.style.zIndex = 10;
var class_div = document.createElement("div");
class_div.className = 'dygraph-label dygraph-title';