*{
    margin: 0 auto;
    box-sizing: border-box;
    background-color: beige;
}


#box {
    width: 100px;
    height: 100px;
    background: #3498db;
    position: absolute;
    top: 100px;
    left: 50px;
    opacity: 0;
}

#boxtwo {
    width: 100px;
    height: 100px;
    background: orchid;
    position: absolute;
    top: 50px;
    left: 100px;
    opacity: 0;
}

#boxthree {
    width: 800px;
    height: 200px;
    background-color: coral;
    color: #309898;
    font-size: 25px;
    /* chose not to use percentage - Demonstration */
    display: flex;
    text-align: center;
    align-items: center;
    border: none;
}

h1{
    border-width: 2px;
    border-color: #8ACCD5;
    border-style: solid;
    background-color: lightsalmon;
}

h1 em{
    background-color: lightsalmon;
}