add color benchmarks

Cargo.toml

@@ -22,6 +22,10 @@ name = "grass"
 path = "src/lib.rs"
 crate-type = ["cdylib", "rlib"]
 
+[[bench]]
+name = "colors"
+harness = false
+
 [[bench]]
 name = "numbers"
 harness = false

benches/colors.rs

@@ -0,0 +1,21 @@
+use criterion::{black_box, criterion_group, criterion_main, Criterion};
+use grass::StyleSheet;
+
+pub fn many_hsla(c: &mut Criterion) {
+    c.bench_function("many_hsla", |b| {
+        b.iter(|| StyleSheet::new(black_box(include_str!("many_hsla.scss").to_string())))
+    });
+}
+
+pub fn many_named_colors(c: &mut Criterion) {
+    c.bench_function("many_named_colors", |b| {
+        b.iter(|| {
+            StyleSheet::new(black_box(
+                include_str!("many_named_colors.scss").to_string(),
+            ))
+        })
+    });
+}
+
+criterion_group!(benches, many_hsla, many_named_colors,);
+criterion_main!(benches);