.btn
{  
   height: 100px;
   width: 100px;
   border-radius: 50%;
   display: flex;
   justify-content: center;
   align-items: center;
   position: fixed;
   right: 20px;
   bottom: 20px;
}

.icone
{
   width: 50px;
   cursor: pointer;

}

h1 {text-align: center;}
h2 {text-align: center;}
h3 {text-align: center;}
h4 {text-align: center;}
h5 {text-align: center;}
li {text-align: center;}



button{

  background-color: rgb(181, 21, 78);
  border: 0;
  line-height: 1.5;
  padding: 0 20px;
  font-size: 1rem;
  text-align: center;
  color: #fff;
  text-shadow: 1px 1px 1px #000;
  border-radius: 10px;
  background-image: linear-gradient(to top left, rgba(0, 0, 0, 0.2), rgba(0, 0, 0, 0.2) 30%, rgba(0, 0, 0, 0));
  box-shadow: inset 2px 2px 3px rgba(255, 255, 255, 0.6), inset -2px -2px 3px rgba(0, 0, 0, 0.6);
}

img{

   width: 20%;
   margin-right: auto;
   margin-left: auto;
   display: block;
  
   
}


a{

   background-color: blue;
   text-decoration: none;

}

a:hover
{
   background-color: aliceblue;
}