.CodeMirror-minimap {
    position: absolute;
    top: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, .1);
}

.CodeMirror-minimap:hover .CodeMirror-minimap__slider {
    background: rgba(0, 0, 0, .3);
}

.CodeMirror-minimap__slider {
    width: 100%;
    height: 0px;
    position: absolute;
    top: 0;
    left: 0;
    z-index: 10;
    background: rgba(0, 0, 0, .1);
    transform: translateY(0px);
    transition: transform .1s, background-color .2s;
}