index.css

html,
body {
  margin: 0;
  padding: 0;
  background-color: black;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol";
}
#app {
}
article {
  background-color: white;
  width: 100%;
  height: 100%;
  overflow: auto;
}
.lm_popin {
  background-color: black;
}
.react-contextmenu-wrapper {
  width: 100%;
  height: 100%;
}
.react-contextmenu--visible {
  z-index: 21;
}

/* Fancy scrollbars. https://codepen.io/devstreak/pen/dMYgeO */
::-webkit-scrollbar
{
  width: 8px;
  height: 8px;
}
::-webkit-scrollbar-track
{
  -webkit-box-shadow: inset 0 0 6px rgba(0,0,0,0.3);
  border-radius: 8px;
}
::-webkit-scrollbar-track:hover
{
  -webkit-box-shadow: inset 0 0 6px rgba(0,0,0,0.3);
  border-radius: 8px;
  background-color: rgba(255, 255, 255, .15);
}
::-webkit-scrollbar-thumb
{
  border-radius: 8px;
  -webkit-box-shadow: inset 0 0 6px rgba(0,0,0,.3);
  background-color: #555;
}
::-webkit-scrollbar-thumb:hover
{
  border-radius: 8px;
  -webkit-box-shadow: inset 0 0 6px rgba(0,0,0,.3);
  background-color: #AAA;
}

/* Icon hack */
.octicon.valign-middle {
  vertical-align: middle;
}

/* TODO: Put this into the contextmenu component. */
.react-contextmenu {
    min-width: 160px;
    padding: 0;
    margin: 2px 0 0;
    font-size: 16px;
    color: #373a3c;
    text-align: left;
    background-color: #fff;
    background-clip: padding-box;
    border: 1px solid rgba(0,0,0,.15);
    outline: none;
    opacity: 0;
    pointer-events: none;
    transition: opacity 250ms ease !important;
}

.react-contextmenu.react-contextmenu--visible {
    opacity: 1;
    pointer-events: auto;
}

.react-contextmenu-item {
    padding: 3px 20px;
    font-weight: 400;
    line-height: 1.5;
    color: #373a3c;
    text-align: inherit;
    white-space: nowrap;
    background: 0 0;
    border: 0;
    border-bottom: 1px solid rgba(0,0,0,.15);
	  cursor: pointer;
}
.react-contextmenu-item:last-child {
  border-bottom: none;
}
.react-contextmenu-item .icon {
    position: absolute;
    right: 0;
}

.react-contextmenu-item.react-contextmenu-item--active,
.react-contextmenu-item.react-contextmenu-item--selected {
    background-color: #DDD;
    outline: solid 1px #20a0ff;
    text-decoration: none;
    border-bottom-color: transparent;
}

.react-contextmenu-item.react-contextmenu-item--disabled,
.react-contextmenu-item.react-contextmenu-item--disabled:hover {
    color: #878a8c;
    background-color: transparent;
    border-color: rgba(0,0,0,.15);
    text-decoration: line-through;
    outline: none;
}

.react-contextmenu-item--divider {
    margin-bottom: 3px;
    padding: 2px 0;
    border-bottom: 1px solid rgba(0,0,0,.15);
    cursor: inherit;
}
.react-contextmenu-item--divider:hover {
    background-color: transparent;
    border-color: rgba(0,0,0,.15);
}

.react-contextmenu-item.react-contextmenu-submenu {
	padding: 0;
  border-bottom: none;
}

.react-contextmenu-item.react-contextmenu-submenu > .react-contextmenu-item:after {
    content: "\0025B6"; /*"◀ ▶ ▲ ▼";*/
    font-family: "Arial", "Liberation Sans", sans-serif; /* Needed to avoid Segoe UI Emoji used by navigation tree */
    display: inline-block;
    position: absolute;
    right: 7px;
}

.example-multiple-targets::after {
    content: attr(data-count);
    display: block;
}