Darken Video Background

Question

How to Darken Background in a video without affecting the text over it?

 <div class="fullscreen-bg">   
    <video loop muted autoplay poster="img/videoframe.jpg" class="fullscreen-bg__video">
        <source src="images/instituteVideo.webm" type="video/webm">
    </video>
    <div class="text-vid">
        <h2 class="texts">Transform into a Smart Institute</h2>
    </div>
</div>

.fullscreen-bg {    
            top: 0;
            right: 0;
            bottom: 0;
            left: 0;
            height: 84vh;
            width: 100%;
            overflow: hidden;
            object-fit: cover;
            z-index: -99;
            position: relative;
            filter: brightness(75%);
    }

    .text-vid {
            position: absolute;
            top:10%;
     }

This is what i have tried , i have also tried using background-color which doesn't work. Using filter darkens the background , but also affects the text color

Answer 1

Simply add this-

video {
   filter: brightness(50%);
}