body {
    margin: 0;
    background-color: #fff;
}

.box {
    margin: auto;
    width: 50vw;
    height: 50vh;
    box-sizing: border-box;
    text-align: center;
    margin-top: 10vh;
    color: #fffe;
    font-size: 16px;
    background-color: #09f;
    padding: 10vh 20px;
    border-radius: 10px;
    box-shadow:  0 0 20px 0 #09f9;
}

.box_title {
    width: 100%;
    margin: 0;
    font-size: 2em;
}

.box_subtitle {
    width: 100%;
    font-size: 1em;
}

.box_content {
    width: 100%;
    font-size: 0.9em;
}