diff --git a/frontend/src/views/Reader.vue b/frontend/src/views/Reader.vue
index c22a173..0adc424 100644
--- a/frontend/src/views/Reader.vue
+++ b/frontend/src/views/Reader.vue
@@ -122,7 +122,7 @@ export default {
     },
 
     setOrientation () {
-      let image = this.$refs.currentImage
+      const image = this.$refs.currentImage
 
       if (image.width < image.height) {
         this.orientation = 'vertical'