Hint for first part

assets/styles/game1.css

@@ -47,6 +47,10 @@ div#message-container {
     font-size: 20px;
 }
 
+div.message {
+    color: #C0C0C0;
+}
+
 div#input {
     padding: 20px;
 }
@@ -54,10 +58,32 @@ div#input {
 input#input-message {
     width: 100%;
     padding: 10px;
-    background: #000;
-    border: 1px solid #F00;
-    color: #F00;
+    background: #111;
+    border: 1px solid #A00000;
+    color: #C0C0C0;
     font-size: 18px;
     box-sizing: border-box;
     font-family: monospace;
 }
+
+.flash-red::after {
+    content: '';
+    position: fixed;
+    bottom: 0;
+    left: 0;
+    right: 0;
+    height: 100px;
+    pointer-events: none;
+    background: linear-gradient(to top, rgba(255, 0, 0, 0.8), transparent);
+    animation: flash-red-anim 0.1s linear forwards;
+    z-index: 9999;
+}
+
+@keyframes flash-red-anim {
+    0% {
+        opacity: 1;
+    }
+    100% {
+        opacity: 0;
+    }
+}