.header{position:fixed; top:0; left:0; width:100%; background:#000; padding:1px 0; text-align:center; z-index:1000}
.header ul{display:flex; justify-content:space-around; align-items:center; list-style:none; padding:0; margin:0}
.header ul li a{color:#fff; text-decoration:none; padding:10px 20px; display:block}
.header ul li a:hover{color:gold; transform:scale(1.1)}

.soundbtn{display:inline-block; width:6px; height:9px; padding:10px 20px; background:var(--blue); color:#fff; border-radius:5px; border:2px solid #000}
/* Navigation enger auf Mobile */
@media (max-width: 900px){
  .header ul{ gap: 4px; }
  .header ul li a{ padding: 8px 10px; font-size: .95rem; }
}
/* Wenn’s sehr eng wird, umbrechen: */
@media (max-width: 640px){
  .header ul{
    flex-wrap: wrap;
    row-gap: 6px;
    justify-content: center;
  }
}