[tooltip]:before {
    /* needed - do not touch */
    content: attr(tooltip);
    position: absolute;
    opacity: 0;
    
    /* customizable */
    /* transition: all 0.15s ease;*/
    transition: all 0.0s ease;
    padding: 10px;
    color: #333;
    border-radius: 10px;
    box-shadow: 2px 2px 1px silver;    
    font-size: 18px;
}

[tooltip]:hover:before {
    /* needed - do not touch */
    opacity: 1;
    
    /* customizable */
    background: #F0ECE9;
    margin-top: -50px;
    margin-left: 20px;    
}

[tooltip]:not([tooltip-persistent]):before {
    pointer-events: none;
}

/* FOR TEST PURPOSES ONLY */
xxdiv {
    border: 1px solid silver;
    background: #ddd;
    margin: 20px;
    padding: 10px;
}