ul class="collapse">
  <li><a href="#examples" id="toc-examples" class="nav-link" data-scroll-target="#examples">Examples</a>
  <ul class="collapse">
  <li><a href="#triangle-distribution" id="toc-triangle-distribution" class="nav-link" data-scroll-target="#triangle-distribution">Triangle distribution</a></li>
  <li><a href="#exponential-distribution" id="toc-exponential-distribution" class="nav-link" data-scroll-target="#exponential-distribution">Exponential distribution</a></li>
  <li><a href="#bivariate-