.intro1 {
font-family: "Ubuntu Mono", monospace;
font-weight: 700;
font-style: normal;
text-align: center; 
}

.intro2 {  
font-family: "Ubuntu Mono", monospace;
font-weight: 400;
font-style: normal; 
text-align: center;
}

.end {
width: 20%;
margin: 0 auto;
border: 4px solid gainsboro;
transition-duration: 0.1s;   
}

.start {
width: 20%;
margin: 0 auto;
border: 4px solid orange;
transition-duration: 0.1s;
}

.start:hover {
background: whitesmoke;    
}

.end:hover {
background: whitesmoke;    
}