IPython/html/static/notebook/less/notificationarea.less

#notification_area {
    .pull-right();
    
    z-index: 10;
}

.indicator_area {
    color: @navbar-default-link-color;
    padding: 4px 3px;
    margin: 0px;
    width: 11px;
    z-index: 10;
    text-align: center;
}

#kernel_indicator {
    .pull-right();
    .indicator_area();

    margin-right: 12px;
}

#modal_indicator {
    .pull-right();
    .indicator_area();
    
    margin-right: 5px;
}

.edit_mode_icon:before {
     content: @fa-var-pencil;
}

.command_mode_icon:before {
     content: ' ';
}

.kernel_idle_icon:before {
     content: @fa-var-circle-o;
}

.kernel_busy_icon:before {
     content: @fa-var-circle;
}