h1{
  text-decoration : underline;
  font-family : Times New Roman; 
  text-align : center;

}


html { 
  margin : 0;
  padding : 0;
  background-color : white; 
}
header{
 background: black;
 color: white
 padding: 10px;
}

section {
 background: black;
 padding: 10px;
 color: white
}

h3 {
  text-decoration : underline;
}

.flex-container {
    display: flex;
    background: black;
    margin: 5px;
    padding: 10px;

}

.flex-item {
  height: 10vh;
  width: 20%;
  margin: 5px;
  padding: 5px;
  font-size: 20px;
}
<img src="gif/musique.gif">
