I looked at HTML code of my page and found four lines in one series. When I change the style, only one line (the last) change width. Others have stroke-width="6","4","2". Because of this line on the chart seems thick. I think these lines are needed to show the shadows. How can I make a single line without a shadow?
<path id="ext-sprite-1114" style="-webkit-tap-highlight-color: rgba(0, 0, 0, 0); " zIndex="0" d="M64,336L94.87,319.7L125.73,303.4L156.6,287.1L187.47,270.8L218.33" stroke-width="6" stroke-opacity="0.05" stroke="rgb(0, 0, 0)" hidden="false" fill="none" transform="matrix(1,0,0,1,1,1)"></path>
<path id="ext-sprite-1115" style="-webkit-tap-highlight-color: rgba(0, 0, 0, 0); " zIndex="0" d="M64,336L94.87,319.7L125.73,303.4L156.6,287.1L187.47,270.8L218.33" stroke-width="4" stroke-opacity="0.1" stroke="rgb(0, 0, 0)" hidden="false" fill="none" transform="matrix(1,0,0,1,1,1)"></path>
<path id="ext-sprite-1115" style="-webkit-tap-highlight-color: rgba(0, 0, 0, 0); " zIndex="0" d="M64,336L94.87,319.7L125.73,303.4L156.6,287.1L187.47,270.8L218.33" stroke-width="2" stroke-opacity="0.15" stroke="rgb(0, 0, 0)" hidden="false" fill="none" transform="matrix(1,0,0,1,1,1)"></path>
<path id="ext-sprite-1113" style="-webkit-tap-highlight-color: rgba(0, 0, 0, 0); " zIndex="0" d="M64,336L94.87,319.7L125.73,303.4L156.6,287.1L187.47,270.8L218.33" stroke="blue" height="1" width="1" stroke-width="1" fill="none" transform="matrix(1,0,0,1,0,0)" hidden="false"></path>