code: function check(node) {
      var initial = start(node).offset
      var final = end(node).offset
  
      if (generated(node)) {
        return null
      }
  
      return node.lang || /^\s*([~`])\1{2,}/.test(contents.slice(initial, final))
        ? 'fenced'
        : 'indented'
    }
docs: Get the style of `node`.