Looking for a way to make 4:3 streaming video fit 16:9 screen?

[Hstv_Dev]

I’m using CSS to control the stretch of the content like this.

<style>
#videos_container{
				position: relative;
        width: 100%;
        height: 0;
        padding-bottom: 56.25%; /* 16:9 aspect ratio (9 / 16 = 0.5625 or 56.25%) */
        overflow: hidden;
			}
		#videos_container video {
				position: absolute;
        top: 0;
        left: 50%;
        transform: translateX(-50%);
        width: 100vw;
        height: 100vh;
        object-fit: fill;
}
</style>

The effects of the show in the simulator are stretched to full screen.

But in the production, in the model 43UQ75, this image is obtained :

I would like to know how to fix it.

[Hstv_Dev]

I try to simulate in the program and full screen like this:

[narae0.kim]

The aspect ratio of a video can be controlled in the TV settings menu, not in the app. Thank you.