.tool_tip {
width: 100%;
position: relative;
display: inline-block;
}
.tool_tip .tool_tip_text {
width: 100%;
bottom: 100%;
left: 50%;
margin-left: -50%;
background-color: #5e5e5e;
color: #fff;
text-align: left;
padding: 5px 0;
border-radius: 6px;
position: absolute;
z-index: 1;
transition: opacity 1s;
opacity: 0;
visibility: hidden;
}
.tool_tip:hover .tool_tip_text {
opacity: 1;
visibility: visible;
}