Flexbox does not work in Safari, striked out in Web inspector

Question

I'm using display: flexbox for a div container cointaining a number of squares (to make them align nicely horizontally), and it works fine in Chrome, but not in Safari 8.0, where it's striked out like this:

#grid {
    overflow-x: hidden;
    overflow-y: scroll;

    position: absolute;
    top: 55px;
    left: 415px;
    bottom: 10px;
    right: 10px;

    display: flex;
    justify-content: space-between;
    flex-direction: row;
    flex-wrap: wrap;
}

.square {
    width: 166px;
    height: 185px;
    position: relative;
    cursor: pointer;
    background-size: 166px 125px !important;
    background-repeat: no-repeat !important;
    background: #FFF;
    margin-right: 20px;
    float: left;
}

Answer 1

You need use prefix so does safari supports

#grid {
    overflow-x: hidden;
    overflow-y: scroll;
    position: absolute;
    top: 55px;
    left: 415px;
    bottom: 10px;
    right: 10px;
    display: flex;
    justify-content: space-between;
    flex-direction: row;
    flex-wrap: wrap;
    display: -webkit-flex;
    -webkit-justify-content: space-between;
    -webkit-flex-direction: row;
    -webkit-flex-wrap: wrap;
}