// sizes $columns: !default; $maxWidth: 1rem !default; $gutter: 1rem !default; *, *::after, *::before { box-sizing: box; } 12 .demo { box-sizing: border-box; background-color: rgba(red, %); 15 outline: 1px solid crimson; padding: 1rem; display: grid; place-content: center; color: red; 20 } .container {