/* widths werden am äußersten Rahmen eines Elements gemessen */
* {
    box-sizing: border-box;
}

.row {margin-bottom:.5em;}

/* Float der Boxen */
[class*="col-"] {
    float: left;
    padding: 15px;
    text-align: center;
}

/* nach einem Row-Element (voller Columns) soll das Floating beendet werden */
.row::after {
    content: "";
    clear: both;
    display: table;
}

/* Grid Colums 12 */
.col-1 {width: 8.33%;}
.col-2 {width: 16.66%;}
.col-23 {width: 20%;}
.col-3 {width: 25%;}
.col-4 {width: 33.33%;}
.col-5 {width: 41.66%;}
.col-6 {width: 50%;}
.col-7 {width: 58.33%;}
.col-8 {width: 66.66%;}
.col-9 {width: 75%;}
.col-91 {width: 80%;}
.col-10 {width: 83.33%;}
.col-11 {width: 91.66%;}
.col-12 {width: 100%;}