.flex-container {
width: 80%;
min-height: 300px;
display: -webkit-flex; /* Safari */
display: flex; /* Standard syntax */
color: white;
border: solid 1px black;
}
.flex-container .item1 {
background: red;
-webkit-flex: 1; /* Safari */
-ms-flex: 1; /* IE 10 */
flex: 1; /* Standard syntax */
}
.flex-container .item2 {
background: green;
-webkit-flex: 1; /* Safari */
-ms-flex: 1; /* IE 10 */
flex: 1; /* Standard syntax */
}
.flex-container .item3 {
background: blue;
-webkit-flex: 1; /* Safari */
-ms-flex: 1; /* IE 10 */
flex: 1; /* Standard syntax */
}