.slide {
  display: none; 
  border: 3px dotted lightgrey; 
  font-size: 4vw; 
  font-family: sans-serif; 
  background-color: inherit;
  white-space: pre-line; 
}

#background {
	position: fixed;
	top: 0;
	left: 0;
	z-index: -100;
}

#lyrics {
  background-color: ;
}
#lyrics > div { 
    position: absolute; 
    top: 10px; 
    left: 10px; 
    right: 10px; 
    bottom: 10px; 
    display: flex;
    align-items: center; 
    justify-content:  center;
}

.slide:first-line { line-height: 0 !important; }
.slide:nth-of-type(1) {display: inherit; }
.slide:nth-of-type(3) {background-color: blue; opacity: 0.5;}
.slide:nth-of-type(6) {background-color: brown; opacity: 0.5;}


/* btn - ovladani */
.btn { border: 1px dashed grey;
 position: fixed; 
 background-color: ;
z-index: 99; 
display: block;
}
.next {
bottom: 0px; 
right: 0px;
width: 40vw; 
height: 20vw; 
}

.prev {
bottom: 0px; 
left: 0px;
width: 40vw; 
height: 20vw; 
}

.back {
top: 0px; 
left: 0px; 
width: 4vw; 
height: 4vw; 
}