[Chartjs]-Chart.js vertical line when hovering and shadow on line

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You can customize various things with a Chart Js library (docs).

To add shadows to chart lines you can use Chart.controllers.line and create a function to draw the shadow.

Example for shadows:

let draw = Chart.controllers.line.prototype.draw;
Chart.controllers.line = Chart.controllers.line.extend({
    draw: function() {
        draw.apply(this, arguments);
        let ctx = this.chart.chart.ctx;
        let _stroke = ctx.stroke;
        ctx.stroke = function() {
            ctx.save();
            ctx.shadowColor = '#000000';
            ctx.shadowBlur = 10;
            ctx.shadowOffsetX = 0;
            ctx.shadowOffsetY = 4;
            _stroke.apply(this, arguments)
            ctx.restore();
        }
    }
});

And to create vertical lines you can use Chart.defaults.LineWithLine and create a function to draw the vertical line too.

Example:

Chart.defaults.LineWithLine = Chart.defaults.line;
Chart.controllers.LineWithLine = Chart.controllers.line.extend({
   draw: function(ease) {
      Chart.controllers.line.prototype.draw.call(this, ease);

      if (this.chart.tooltip._active && this.chart.tooltip._active.length) {
         var activePoint = this.chart.tooltip._active[0],
             ctx = this.chart.ctx,
             x = activePoint.tooltipPosition().x,
             topY = this.chart.scales['y-axis-0'].top,
             bottomY = this.chart.scales['y-axis-0'].bottom;

         // draw line
         ctx.save();
         ctx.beginPath();
         ctx.moveTo(x, topY);
         ctx.lineTo(x, bottomY);
         ctx.lineWidth = 2;
         ctx.strokeStyle = '#07C';
         ctx.stroke();
         ctx.restore();
      }
   }
});

follow the complete code for your question in my Fiddle

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