diff --git a/Cargo.toml b/Cargo.toml
index c7b08f4..1cdc1e1 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -32,7 +32,6 @@ rand = { version = "0.7.3", optional = true }
 codemap = "0.1.3"
 peekmore = "0.4.0"
 wasm-bindgen = { version = "0.2.60", optional = true }
-bimap = "0.4.0"
 
 [features]
 default = ["commandline", "random"]
diff --git a/src/color/mod.rs b/src/color/mod.rs
index 57f82d5..fb7aef4 100644
--- a/src/color/mod.rs
+++ b/src/color/mod.rs
@@ -498,7 +498,7 @@ fn repr(red: &Number, green: &Number, blue: &Number, alpha: &Number) -> String {
 
     if alpha < &Number::one() {
         format!("rgba({}, {}, {}, {})", red_u8, green_u8, blue_u8, alpha)
-    } else if let Some(c) = NAMED_COLORS.get_by_right(&[red_u8, green_u8, blue_u8, 0xFF]) {
+    } else if let Some(c) = NAMED_COLORS.get_by_rgba(&[red_u8, green_u8, blue_u8, 0xFF]) {
         (*c).to_string()
     } else {
         format!("#{:0>2x}{:0>2x}{:0>2x}", red_u8, green_u8, blue_u8)
diff --git a/src/color/name.rs b/src/color/name.rs
index c01e4f3..d613224 100644
--- a/src/color/name.rs
+++ b/src/color/name.rs
@@ -1,11 +1,38 @@
 //! A big dictionary of named colors and their
 //! corresponding RGBA values
 
-use bimap::BiMap;
 use once_cell::sync::Lazy;
+use std::collections::HashMap;
 
-pub(crate) static NAMED_COLORS: Lazy<BiMap<&'static str, [u8; 4]>> = Lazy::new(|| {
-    let mut m = BiMap::with_capacity(150);
+pub(crate) struct NamedColorMap {
+    name_to_rgba: HashMap<&'static str, [u8; 4]>,
+    rgba_to_name: HashMap<[u8; 4], &'static str>,
+}
+
+impl NamedColorMap {
+    pub fn with_capacity(capacity: usize) -> Self {
+        Self {
+            name_to_rgba: HashMap::with_capacity(capacity),
+            rgba_to_name: HashMap::with_capacity(capacity),
+        }
+    }
+
+    pub fn insert(&mut self, name: &'static str, rgba: [u8; 4]) {
+        self.name_to_rgba.insert(name, rgba);
+        self.rgba_to_name.insert(rgba, name);
+    }
+
+    pub fn get_by_name(&self, name: &str) -> Option<&[u8; 4]> {
+        self.name_to_rgba.get(name)
+    }
+
+    pub fn get_by_rgba(&self, rgba: &[u8; 4]) -> Option<&&str> {
+        self.rgba_to_name.get(rgba)
+    }
+}
+
+pub(crate) static NAMED_COLORS: Lazy<NamedColorMap> = Lazy::new(|| {
+    let mut m = NamedColorMap::with_capacity(150);
     m.insert("aliceblue", [0xF0, 0xF8, 0xFF, 0xFF]);
     m.insert("antiquewhite", [0xFA, 0xEB, 0xD7, 0xFF]);
     m.insert("aqua", [0x00, 0xFF, 0xFF, 0xFF]);
diff --git a/src/value/parse.rs b/src/value/parse.rs
index e205395..04c2602 100644
--- a/src/value/parse.rs
+++ b/src/value/parse.rs
@@ -586,7 +586,7 @@ impl Value {
             ));
         }
 
-        if let Some(c) = NAMED_COLORS.get_by_left(&lower.as_str()) {
+        if let Some(c) = NAMED_COLORS.get_by_name(&lower.as_str()) {
             return Ok(IntermediateValue::Value(Spanned {
                 node: Value::Color(Box::new(Color::new(c[0], c[1], c[2], c[3], s))),
                 span,