@mixin card { backdrop-filter: blur(16px); background-color: rgba(0, 0, 0, 0.15); border: 2px solid white; border-radius: 12px; &:focus { outline: none; border: 4px solid white; } } @mixin center-children { display: flex; justify-content: center; align-items: center; } @mixin square($size) { width: $size; height: $size; }