Hello aashaymehta,
Thanks for contacting us again!
To render the vertical lines, you need to render them customarily. We have a special
renderer method on a chart instance that allows you to render custom SVG elements. You can find a list of possible elements and their properties here:
https://api.highcharts.com/class-refere ... derer#rect. As you can see by clicking on this link, the
rect method is chosen as this is the one I recommend you use. I've updated your example by rendering this custom element inside the chart's
load event, also showing you how to adjust the proper positions, take a look:
https://jsfiddle.net/BlackLabel/94p7r13s/.
According to your second question, you need to use the
linearGradient declared as
series.data.color property to achieve an effect of a colored bar. It's also shown in the above example (the first bar). Feel free to read more about the gradients here:
https://api.highcharts.com/class-refere ... bject#toc0.
Let me know if you found it helpful,
Kind Regards!