#video-canvas-bg {
    position: fixed !important;

    top: 0 !important;
    left: 0 !important;

    width: 100vw !important;
    height: 100vh !important;

    display: block !important;

    /*
     * Canvas itself remains transparent.
     * The video frames are drawn by JavaScript.
     */
    background: transparent !important;
    background-color: transparent !important;

    /*
     * Visual background layer.
     */
    z-index: 0 !important;

    /*
     * Canvas must never intercept clicks,
     * navigation, buttons, etc.
     */
    pointer-events: none !important;

    /*
     * Prevent accidental spacing/inline behavior.
     */
    margin: 0 !important;
    padding: 0 !important;
    border: 0 !important;

    /*
     * Keep the canvas from participating in document layout.
     */
    overflow: hidden !important;

    /*
     * Rendering optimization.
     */
    transform: translateZ(0);
    backface-visibility: hidden;

    /*
     * Let JavaScript control the actual drawing dimensions.
     */
    image-rendering: auto;
}