https://github.com/viswanath-lab/RadQy/tree/master

modify css file for better chart visibility:

.background-path {
	fill: none;
	stroke: #ddd;
	shape-rendering: crispEdges;
	opacity: 0.1;
}

.foreground-path {
	fill: none;
	/*stroke: #007bff;*/
	stroke: #00304e;
	opacity: 0.1;
}

.selected-foreground-path {
	fill: none;
	/*stroke: var(--selected-color);*/
	stroke: var(--selected-color);
	stroke-width: 10;
	opacity: 1;
}