lse if ((page = panel.querySelector('.is-current-url'))) page.classList.add('is-provisional')
  } else {
    page = panel.querySelector('.is-current-url')
  }
  if (page) {
    var ancestor = page
    while ((ancestor = ancestor.parentNode) && ancestor !== panel) {
      if (ancestor.className === 'nav-item') ancestor.classList.add('is-current-path', 'is-active')
    }
    page.classList.add('is-current-page', 'is-active')
    if (panel.scrollHeight > panel.clientHeight) {
      var panelRect = panel.getBou