.menu-button{width:46px;height:46px;padding:10px;border:1px solid var(--line);border-radius:10px;background:#fff}
.menu-button span{display:block;width:24px;height:3px;margin:4px auto;border-radius:2px;background:var(--ink);transition:transform .2s,opacity .2s}
.menu-button.open span:nth-child(1){transform:translateY(7px) rotate(45deg)}
.menu-button.open span:nth-child(2){opacity:0}
.menu-button.open span:nth-child(3){transform:translateY(-7px) rotate(-45deg)}