*{
    margin: 0; padding: 0;
}

body{
    background-color: black;
}
footer{
    position: fixed; bottom: 0; padding: 5px; width: 100%;
    display: flex; align-items: center; justify-content: center;
    background: linear-gradient(0deg,rgba(112, 112, 112, 1) 0%, rgba(255, 255, 255, 0) 100%);
}
a{
    color: white; width: 200px;
}

.lungs{
    scale: 0.5;
}
.overlay{
    height: 550px; width: 543px;
    position: absolute; bottom: 0;
    
}
#lung1{
    float: left;
}
#lung2{
    float: right;
}

#lung1:hover, #lung2:hover{
    filter: brightness(1.5)
}