img { 
    width: 100%; 
    height: 100%; 
} 
input { 
    display: none; 
} 
.audioElm div > h2 { 
    width: 100%; 
    background-color: green; 
    text-align: center;  
    margin-bottom: 2vh;
} 
.audioElm button {  
    width: 7em; 
    height: 90%; 
    background-color: blue; 
    margin-left: 0.3em; 
} 
.audioElm > div { 
    width: 75%; 
    height: 80%; 
    background-color: yellow; 
    margin-left: 2%;
} 
.audioElm > div > div {    
    width: 100%; 
    height: 10%;   
    position: relative;  
    background-color: blue;
} 
.audioElm > div > div > div {  
    background-color: pink; 
    width: 0.5em; 
    height: 2em;  
    position: absolute; 
    top: -150%;
} 

.btn { 
    background-color: yellow; 
}

.container-fluid { 
    background-color: red; 
} 
.col-sm-0 { 
    background-color: blue;  
} 
.col-sm-12 { 
    background-color: green; 
} 
.col { 
    height: 10vh; 
} 

.non-primary-button { 
    width: 6em; 
    height: 90%;    
}  
.primary-button { 
    width: 18em; 
    height: 100%; 
}  
.button-spacer { 
    width: 2%; 
}
.hide { 
    display: none; 
}  
.audioElm { 
    width: 100%; 
    height: 13vh; 
    margin-top: 1em; 
    background-color: red;  
    position: relative;
} 



#play-pause {  
    width: 100%; 
    height: 5em;  
}  
#song-files { 
    background-color: orange; 
} 
#controls { 
    background-color: blue;   
} 
#time-line { 
    margin-top: 1em;   
    background-color: red;
} 
#custom-file-upload { 
    width: 8em; 
    height: 6.5em;  
    background-color: pink;    
    margin-top: 1em; 
} 
#add-files { 
    padding-bottom: 0.5em; 
} 
#time { 
    width: 95%;  
    position: relative; 
    height: 1em;  
    background-color: yellow;
} 
#main-line { 
    width: 1em; 
    height: 3em; 
    background-color: pink;  
    position: absolute; 
    left: 0; 
    top: -100%; 
    
    
    
}