Diff with Razor language not working

[lechihuy]

Hi team, I try using Torchlight to highlight a Razor code that using Diff but it's seem not working.

```razor
@page
@model IndexModel
@{
    ViewData["Title"] = "Home page";
}

<div class="text-center">
    <h1 class="display-4">Welcome</h1>
    <p>Learn about <a href="https://docs.microsoft.com/aspnet/core">building Web apps with ASP.NET Core</a>.</p> // [tl! --]
    <p>Hello, world! The time on the server is @DateTime.Now</p> // [tl! ++]
 </div>

I hope Torchlight team fix it help me. Thanks so much.