.flex_container{
    display: flex;
    flex-flow: row wrap;
    flex-direction: row;
    justify-content: space-around;
    align-items: center;
    max-width: 800;
    margin-top: inherit;
    clear: both;
}

.flex_item{   
    flex-grow: 1;
    flex-basis: auto;
    margin-right: 25px;
    margin-left: 25px;
    max-width:300px
}
.wrapper{
    min-width: 800px;
    max-width: 1400px;
    margin: auto
}
header{
    margin: auto;
    max-width: inherit;
    margin-top: 0px;
    clear:both;
}
.main_picture{
    min-width: 800px;
    max-width: 1400px;
    margin: auto;
}

.flex_item:hover{
    display: block;
}