You need to change the margin values in the code manually.
Left Article margin (currently 10px)
.loadedContent {
padding: 0 0 0 10px !important;;
}
Left YT video margin (currently 10px(last))
.video-player:not(.is-minimized) > .modal-content {
max-width: var(--width-big) !important;
margin: 0 0 10px 10px !important;
border-radius: 0.75rem !important;
}