* {
    background-color: aqua;
}

.header {
    color: aliceblue;
    font-family: 'Ubuntu', sans-serif;
    text-align: center;
    font-size: 6vh;
}
.paragraph {
    color: aliceblue;
    font-family: 'Courier New', Courier, monospace;
    text-align: center;
    font-size: 3vw;
}
.img-hover {
    width: 55vw;
    height: 30vw;
    display: flex;
    margin-left: auto;
    margin-right: auto;
    border-radius: 10vw;
    background-color: white;
    align-items: center;
    justify-content: center;
}
.img-1st {
    width: 50vw;
    height:25vw;
    border-radius: 10vw;
    z-index: 1;
    position: absolute;
}
.img-second {
    width: 50vw;
    height:25vw;
    border-radius: 10vw;
    z-index: 0;
}
.img-1st:hover {
    display: none;
}