add styles

Source-Code/EventCode/style.css

@@ -0,0 +1,38 @@
+* {
+    box-sizing: border-box;
+  }
+
+  body {
+    background-color: floralwhite;
+    font-family: "Segoe UI", sans-serif;
+    margin: 0;
+    overflow: hidden;
+    height: 100vh;
+    padding: 20px;
+    display: flex;
+    justify-content: center;
+    align-items: center;
+  }
+
+  .key{
+    border: 1px solid #999;
+    background-color: #eee;
+    box-shadow: 1px 1px 3px rgba(0, 0, 0, 0.1);
+    align-items: center;
+    font-size: 20px;
+    font-weight: bold;
+    padding: 20px;
+    flex-direction: column;
+    margin: 10px;
+    min-width: 150px;
+    position: relative;
+  }
+  .key small {
+    position: absolute;
+    top: -24px;
+    left: 0;
+    text-align: center;
+    width: 100%;
+    font-size: 14px;
+    color: #555;
+  }