Premiere Pro not exporting at the same exact colours I'm using

Hi, so I need to export some phone mockups for a web page that has this code #0A1435 as background colour, so I need to use the same exact colour on the background (lpha is not considered because I need a very small size file for web).

My phone is a .png element so I create a Color Matte and use the same exact colour, it looks good.

The problem is that when I render this blue is not exactly 0A1435 , it changes to 091436 so it looks bad on the webpage because you can see the change of colour... Any idea what am I doing wrong?

Here I show the problem: https://www.youtube.com/watch?v=vXma4FTfW5M