You can do what you want here!
If you scroll down there are settings you can configure
Changing setting values to high number is not recomended because it can freeze your browser
Just keep in mind you have to click Apply button everytime you change settings
Right click to repel circles
Left click to grab circles
Source code is on github
Circle count
Circle speed
Circle radius
Circle connect radius
Circle color
Circle connect color
Circle mouse repel distance
Circle mouse repel friction