JSFiddle - React, Tailwind, and code Playground

HTML

<div id="tooltipNotifikace">Lorem impsum dolor sit amet</div>

CSS

#tooltipNotifikace {
    color: #1bc204;
    text-align: center;
    position: fixed;
    right: 6px;
    padding: 0px 0px 0px 0px;
    width: 350px;
    max-height: 500px;
    overflow-y: auto;
    background: #fff;
    border: 2px solid #0dbe48;
    z-index: 10160;
}

#tooltipNotifikace:after, #tooltipNotifikace:before {
    bottom: 100%;
    left: 61.5%;
    border: solid transparent;
    content: " ";
    height: 0;
    width: 0;
    position: absolute;
    pointer-events: none;
}

#tooltipNotifikace:after {
    border-color: rgba(136, 183, 213, 0);
    border-bottom-color: #fff;
    border-width: 10px;
    margin-left: -10px;
}

#tooltipNotifikace:before {
    border-color: rgba(194, 225, 245, 0);
    border-bottom-color: #0dbe48;
    border-width: 13px;
    margin-left: -13px;
}