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<div class="tooltip-wrapper">
    <div class="tooltip">blabla</div>
</div>
△ mouseover on red box

body{padding:50px;}
.tooltip-wrapper {
    position: relative;
    width: 14px;
    height: 14px;
    background: red;
}
.tooltip {
    opacity: 0;
    visibility: hidden;
    position: absolute;
    bottom: 30px;
    left: -50px;
    box-sizing: border-box;
    margin-left: 6px;
    padding: 7px 15px;
    width: 100px;
    border: 1px solid #cecece;
    border-radius: 5px;
    background: #fff;
    font-size: 14px;
    text-align: center;
    transform: translateY(10px);
    transition: all .25s ease-out;
    box-shadow: 0px 3px 5px rgba(0, 0, 0, 0.35);
    z-index: 9999
}
.tooltip:after {
    content: '';
    position: absolute;
    bottom: -7px;
    left: 50px;
    right: 0;
    display: block;
    margin-left: -6px;
    width: 12px;
    height: 12px;
    background: #fff;
    border: 1px solid #cecece;
    border-width: 0 1px 1px 0;
    transform: rotate(45deg);
    overflow: hidden;
    box-shadow: 3px 3px 3px rgba(0, 0, 0, 0.35);
}
.tooltip-wrapper:hover .tooltip {
    opacity: 1;
    visibility: visible;
    transform: translateY(0px);
}