* {
    box-sizing: border-box;
    padding: 0;
    margin: 0;
}

body {
    background-color: whitesmoke;
}

.caja1 {
    border: 2px black solid;
    background-color: purple;
    height: 100px;
}

.caja2 {
    border: 2px black solid;
    background-color: #ef9a2b;
    height: 100px;
}

.caja3 {
    border: 2px black solid;
    background-color: purple;
    height: 100px;
}

.caja4 {
    border: 2px black solid;
    background-color: #ef9a2b;
    height: 100px;
}

.caja5 {
    border: 2px black solid;
    background-color: purple;
    height: 100px;
}

.caja6 {
    border: 2px black solid;
    background-color: #ef9a2b;
    height: 100px;
}

.caja7 {
    border: 2px black solid;
    background-color: purple;
    height: 100px;
}

.caja8 {
    border: 2px black solid;
    background-color: #ef9a2b;
    height: 100px;
}

.caja9 {
    border: 2px black solid;
    background-color: purple;
    height: 100px;
}

.caja10 {
    border: 2px black solid;
    background-color: #ef9a2b;
    height: 100px;
}