grass is far from being feature complete! Below you can see what SCSS features are currently supported. My MVP will include values, @mixin, @include, @media, styles, operators, css functions and css at rules.

[] Variables [x] Scoping [x] Shadowing [] Built-in variables [] !default [] !global [x] @import [x] @error [x] @warn [x] @debug [] Styles [x] !important [x] Interpolation [] Nesting [] Custom properties [] Hidden declarations [] Selectors [x] Attributes [x] Parent selector & [x] All other selectors [x] Nesting [] Placeholder selector % [x] Comments [x] Removes single line comments [x] Preserves toplevel multiline comments [x] Removes inline multiline comments [] @mixin [x] Keyword args [x] Default arg values [] Variadic args [] @content [] @include [x] Keyword args [x] Default arg values [] Content blocks [] Functions [] @return [] Control flow [] @if [] @else [] @for [] @while [] @each [] Constant folding [] Unit arithmetic [] CSS at rules [] CSS functions [] calc() [] url() [] element() [] progid:...() [] expression() [] min() [] max() [] @media [] @use [] @extend [] @at-root [] @forward [] Values [] Numbers [] Strings [] Colors [] Lists [] Maps [] Booleans [] Null [] Operators [] Built-in modules [] Content encoding [] WASM bindings