.btn {
    z-index: 1;
    display: flex;
    justify-content: center;
    align-items: center;
    position: fixed;
    bottom: 2rem;
    right: 10px;
    width: 50px;
    height: 50px;
    background-color:var(--azulLaranja);
    border-radius: 10px;
    text-decoration: none;
}

.btn::after {
    content: "↑";
    font-size: 32px;
    font-weight: bold;
    color: var(----pretoBranco);
    transition: margin-top 250ms;  
}
.btn:hover{
    background-color: var(--branco); 
}
.btn:hover::after {
    margin-top:-8px;
    color: #000;
    
}

.ini::after {
    transition: margin-top 250ms;  
}