{{ $marginnoteDomIdSuffix := .Ordinal }}
<label for="marginnote-{{.Page.File.UniqueID}}-{{ $marginnoteDomIdSuffix }}">
    class="margin-toggle">&#8853;
</label>
<input type="checkbox" id="marginnote-{{.Page.File.UniqueID}}-{{ $marginnoteDomIdSuffix }}" class="margin-toggle" />
<span class="marginnote">{{ .Inner }}</span>