diff --git a/hdyc-svelte/src/lib/components/QuickDefinitionCard.svelte b/hdyc-svelte/src/lib/components/QuickDefinitionCard.svelte
index f71e353..745850a 100644
--- a/hdyc-svelte/src/lib/components/QuickDefinitionCard.svelte
+++ b/hdyc-svelte/src/lib/components/QuickDefinitionCard.svelte
@@ -4,11 +4,15 @@
 
   export let config: CalculatorDef;
 
-  const label1 = config.labels.in1 || 'Unit 1';
-  const label2 = config.labels.in2 || 'Unit 2';
+  let label1 = 'Unit 1';
+  let label2 = 'Unit 2';
+  let def1: string | undefined;
+  let def2: string | undefined;
 
-  const def1 = getDefinition(label1);
-  const def2 = getDefinition(label2);
+  $: label1 = config.labels.in1 || 'Unit 1';
+  $: label2 = config.labels.in2 || 'Unit 2';
+  $: def1 = getDefinition(label1);
+  $: def2 = getDefinition(label2);
 </script>
 
 <section class="definition-card">