Please check, I have did Video responsive in following ways.
1st Option You can use media Queries
<video autoplay muted loop id="myVideo">
<source src="https://www.learningcontainer.com/wp-content/uploads/2020/05/sample-mp4-file.mp4" type="video/mp4">
</video>
<style>
#myVideo {
position: fixed;
right: 0;
bottom: 0;
min-width: 100%;
max-height: 100%;
}
@media(max-width: 640px){
#myVideo {
width: 100%;
}
}
</style>
2nd Option set width: 100%
instead of min-width: 100%
<video autoplay muted loop id="myVideo">
<source src="https://www.learningcontainer.com/wp-content/uploads/2020/05/sample-mp4-file.mp4" type="video/mp4">
</video>
<style>
#myVideo {
position: fixed;
right: 0;
bottom: 0;
width: 100%;
max-height: 100%;
}
</style>
3rd Option Add wrapper for video tag and handle the responsive
<div class="video-Wrapper">
<video autoplay muted loop id="myVideo">
<source src="https://www.learningcontainer.com/wp-content/uploads/2020/05/sample-mp4-file.mp4" type="video/mp4">
</video>
</div>
<style>
.video-Wrapper {
position: fixed;
top: 0;
right: 0;
bottom: 0;
left: 0;
background-color: #000;
}
#myVideo {
position: absolute;
right: 0;
bottom: 0;
width: 100%;
max-height: 100%;
}
</style>