.masonry_list ul {
    display: block;
    margin: 0 -2rem;
}
.wrapper .masonry_list ul > li {
    list-style: none;
    padding: 1rem 2rem;
    position: relative;
}
.wrapper .masonry_list ul > li:before {
    content: ''; position: absolute;
    top: 0; left: 2rem; right: 2rem;
    width: auto; height: 1px;
    background-color: currentColor;
}

.wrapper .masonry_list ul > li:nth-child(1):before {content: none;}

@media screen and (min-width:40em){
    .wrapper .masonry_list ul > li {
        width: 50%;
    }
    .wrapper .masonry_list ul > li:nth-child(2):before {content: none;}
}

@media screen and (min-width:64em){
    .wrapper .masonry_list ul > li {
        width: 33.333%;
        padding: 1.5rem 2rem;
    }
    .wrapper .masonry_list ul > li:nth-child(3):before {content: none;}
}