.wrapper {
    border: 1px solid red;
    min-height: 500px;
    font-size: 2rem;
    padding: 1rem;
}

.box1, .box2, .box3 {
    width: 100px;
    height: 100px;
    line-height: 100px;
    text-align: center;
    font-size: 2rem;
    color: white;
    margin: 0;
}

.box1 {
    background-color: red;
}

.box2 {
    background-color: blue;
}

.box3 {
    background-color: #E7C13C;
}