diff --git a/app-proto/src/assembly.rs b/app-proto/src/assembly.rs
index da54210..485448e 100644
--- a/app-proto/src/assembly.rs
+++ b/app-proto/src/assembly.rs
@@ -11,11 +11,13 @@ use crate::engine::{realize_gram, PartialMatrix};
 pub type ElementKey = usize;
 pub type ConstraintKey = usize;
 
+pub type ElementColor = [f32; 3];
+
 #[derive(Clone, PartialEq)]
 pub struct Element {
     pub id: String,
     pub label: String,
-    pub color: [f32; 3],
+    pub color: ElementColor,
     pub representation: DVector<f64>,
     pub constraints: BTreeSet<ConstraintKey>,