body{
    height: 100%;
}

#left {
    width: 85%;
}

.sticky {
    position: sticky;
    top: 0;
    min-height: 2em;
    background: lightpink;
}

#right {
    width: 15%;
    height: 100%;
    overflow: auto;
    position: fixed;
    top: 0;
    right: 0;
}