diff --git a/assets/js/mobile.js b/assets/js/mobile.js
index f99be6b..94749cd 100644
--- a/assets/js/mobile.js
+++ b/assets/js/mobile.js
@@ -15,14 +15,23 @@
     nav.classList.add('js-nav-open');
     sheet.setAttribute('aria-hidden', 'false');
     toggle.setAttribute('aria-expanded', 'true');
+    document.body.addEventListener('keydown', closeonesc);
   }
 
   function navclose() {
     nav.classList.remove('js-nav-open');
     sheet.setAttribute('aria-hidden', 'true');
     toggle.setAttribute('aria-expanded', 'false');
+    document.body.removeEventListener('keydown', closeonesc);
   }
 
+  // Close the nav sheet with "esc" key.
+  function closeonesc(e) {
+    if (e.key === 'Escape') {
+      navclose();
+    }
+  };
+
   // Toggle the mobile nav sheet.
   const toggles = document.querySelectorAll('.mobile-nav__cover, .mobile-nav__toggle');
   toggles.forEach(function (toggle) {