style.css

h1#headerNames {
margin-top: 10%;
color: black;
font-family: space grotesk;
font-size: 150px;
text-align: center;
cursor: pointer;
}

.button {
width: 180px;
  height: 46px;
  margin: auto;
background: black;
border: black;
border-radius: 40px;
color: #fff;
font-family: space grotesk;
font-weight: normal;
text-align: center;
letter-spacing: 0px;
display: block;
cursor: pointer;
}

#stopButton {
background: red;
display: none;
color: white;
border: black;
}

#timerWrapper {
margin: 50px 0;
color: #fff;
font-family: space grotesk;
font-size: 0px;
text-align: center;
opacity: 0;
transition: opacity 1s;
}
#timerWrapper.visible {
opacity: 1;
}
  
ul {
  border: 1px solid #e7e7e7;
  background-color: #f3f3f3;
}

li a {
  color: #666;
}

  
ul {
  margin: 23;
  padding: 0;
  overflow: hidden;
  border: 1px solid #e7e7e7;
  background-color: #f3f3f3;
  border-radius: 40px;
}
    
li {
  float: left;
}

li a {
  display: block;
  color: black;
  text-align: center;
  padding: 14px 40px;
  text-decoration: none;
  font-family: space grotesk;

}

li a:hover:not(.active) {
  background-color: black;
  color: white;
}

li a.active {
  color: white;
  background-color: black;
}