sep_style_for_columns.css

#layout .builder-column {
    z-index: 1;
    border: 1px solid lightgray;
    background-color: transparent;
}
.builder-column {
    background-color: #FFEB3B;
    position: relative;
    float: left;
    margin-bottom: 20px;
}

/*///// 1_2, 1_4... /////*/
.column-1_1 {width: 100%;}
.column-1_2 {width: 50%;}
.column-1_3 {width: 33%}
.column-1_4 {width: 25%;}
.column-1_6 {width: 16.666%;}
.column-2_3 {width: 66.666%;}
.column-2_5 {width: 40%;}
.column-3_5 {width: 60%;}
.column-3_4 {width: 75%;}
.column-4_5 {width: 80%;}
.column-5_6 {width: 83.333%;}
/*///// 1_2, 1_4... /////*/