Added JustREM

JustREM allows you to easily and quickly convert pixel values into rem values.

store.json

@@ -168,6 +168,11 @@
         "title": "CSS Animation",
         "desc": "CSS animation articles, tips and tutorials. Level Up Your CSS Animation Skills.",
         "url": "https://cssanimation.rocks/"
+      },
+      {
+        "title": "JustREM",
+        "desc": "Easily and quickly convert pixel values into rem values.",
+        "url": "https://justrem.xyz/"
       }
     ]
   },
@@ -1058,4 +1063,4 @@
       }
     ]
   }
-]
+]