Video Covering Entire Widget/Row?

Since the video has limited height, we need to either hide some of the text in lower resolutions to reduce the height of the section itself or make the video occupy the height of the section at the cost of losing some portions of the background video.

You can use the following Custom CSS using a plugin like Simple Custom CSS plugin if you do not want to hide any text to reduce height –

@media only screen and (max-width: 1220px) {
    .lsow-hero-header .lsow-html5-video-bg video {
        width: auto;
        height: 100%;
    }
}

The gray background should not appear now.