title: How to draw relationship arrows between DOM elements?
body: <p>There are columns with elements.</p>
  <p>I need to draw relationship arrows between elements.</p>
  <p>Relations can be within the same column, between adjacent or non-adjacent columns.
  Also, the spaces between items should be added automatically to free space for arrows.</p>
  <p>Here is the prototype of what it may look like.</p>
  <p><a href="https://i.stack.imgur.com/4naek.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/4naek.png" alt="enter image description here" /></a></p>
  <p>Could you please recommend the direction for investigation?</p>
  <p>Are there some libraries for that? Should I use SVG, or canvas (or a library based on canvas)? Maybe a table with thousands of cells and with color borders?</p>