Slight refinement on the language filter dropdown

src/App.css

@@ -306,9 +306,9 @@ footer {
 }
 
 .filterHeader button {
-  margin-left: 2em;
-  max-width: 2em;
-  max-height: 2em;
+  margin-left: 1em;
+  width: 1.5em;
+  height: 1.7em;
 }
 
 .langFilters {

src/components/LangFilters.js

@@ -70,8 +70,8 @@ function LangFilters({ changeParameter, data }) {
   return (
     <div className="langFilters">
       <div className="filterHeader">
-        <h3>Select Language</h3>
-        <button onClick={() => setShow(!showFilters)}>+</button>
+        <h3>Filter by Language</h3>
+        <button onClick={() => setShow(!showFilters)}>{showFilters? "-" : "+"}</button>
       </div>
       {showFilters ? filterList : ""}
     </div>