add styling

calculator/style.css

@@ -12,16 +12,40 @@ body {
 .calculator {
     display: grid;
     grid-template-columns: 1fr 1fr 1fr 1fr;
+    border-collapse: collapse;
+    border-radius: 0;
 }
 
-.display {
+#display {
     grid-column: 1 / 5;
-    height: 50px;
-    width: 200px;
+    height: 100px;
+    width: 400px;
+    background-color: black;
+    color: white;
+    text-align: right;
+    font-size: 75px;
 }
 
 button {
-    height: 50px;
+    height: 100px;
+    font-size: 50px;
+    background-color: #d8d9db;
+    border: 1px solid black;
+    padding: 0;
+
+}
+
+button:hover {
+    background-color: #ebebeb;
+}
+
+.operator {
+    background-color: #df974c;
+    color: white;
+}
+
+.operator:hover {
+    background-color: #dfb07e;
 }
 
 .clear {