# [C#][1], 267 bytes

    using System;using System.Linq;class _{static void Main(){var n=DateTime.Now;var t=n.Month==12?n.Day:0;Console.WriteLine(string.Join(" ",Enumerable.Range(1,25).OrderBy(_=>new Random().Next(-1,1)).Select((d,i)=>(i%5==4?"\r\n":"")+(d<t?$"[ ]":d>t?$"{d}":"[@]"))));}}

[.Net Fiddle][2]


  [1]: https://docs.microsoft.com/de-de/dotnet/csharp/
  [2]: https://dotnetfiddle.net/NV5ZID