A sketch of way to generate a decision tree on a website.

tree.js

const selector = "#root > li";
const tree = {
  dom_el: null,
  text: 'root',
  children: []
};

const gen_tree = () => {
  const init = Array.from(document.querySelectorAll(selector));

  const dfs = (parent_node, dom_node) => {
    const tree_node = {
      dom_el: it,
      text: it.textContent,
      children: []
    };
    parent_node.children.push(tree_node);

    const { children } = dom_node;

    if (children.length === 0)
      return;
    
    for (const child of children) {
      if (child.tagName !== "UL")
        continue;

      const child_lis = child.children;
      for (const child_li of child_lis)
        dfs(tree_node, child_li);

      break;
    }
  };

  init.forEach(it => dfs(tree, init));

  console.log(tree);
};