body {
    background-color: lightskyblue;
    color: purple;
}

p {
    text-align: center;
}

.vertical-container {
    height: 300px;
    display: -webkit-flex;
    display: flex;
    -webkit-align-items: center;
    align-items: center;
    -webkit-justify-content: center;
    justify-content: center;
}

h1.vertical-container {
    font-size: 275%;
}