.resizable {
    border: solid 1px black;
    position: fixed;
}

.resizable video {
    cursor: move;
}

.resizer {
    width: 10px;
    height: 10px;
    background: white;
    border-left: solid 1px black;
    border-top: solid 1px black;
    position: absolute;
    right: 0;
    bottom: 0;
    cursor: se-resize;
}