First commit

style.css

@@ -28,7 +28,8 @@ body {
     /* Let clicks pass through to canvas if needed, but start screen needs clicks */
 }
 
-#start-screen {
+#start-screen,
+#loading-screen {
     position: absolute;
     top: 50%;
     left: 50%;
@@ -71,4 +72,67 @@ h1 {
     height: 100%;
     background-color: #fff;
     transition: width 0.1s linear;
+}
+
+#heartbeat {
+    width: 60px;
+    height: 60px;
+    margin-top: 10px;
+}
+
+.heart-icon {
+    fill: #ff3333;
+    animation: pulse 1s infinite;
+}
+
+@keyframes pulse {
+    0% {
+        transform: scale(1);
+        opacity: 0.8;
+    }
+
+    50% {
+        transform: scale(1.2);
+        opacity: 1;
+    }
+
+    100% {
+        transform: scale(1);
+        opacity: 0.8;
+    }
+}
+
+#power-warning {
+    display: none;
+    color: red;
+    font-weight: bold;
+    font-size: 1.5rem;
+    position: absolute;
+    top: 20px;
+    left: 50%;
+    transform: translateX(-50%);
+    text-shadow: 0 0 10px red;
+    animation: flash 0.5s infinite alternate;
+}
+
+@keyframes flash {
+    from {
+        opacity: 0.2;
+    }
+
+    to {
+        opacity: 1;
+    }
+}
+
+#crosshair {
+    position: absolute;
+    top: 50%;
+    left: 50%;
+    width: 4px;
+    height: 4px;
+    background-color: white;
+    transform: translate(-50%, -50%);
+    pointer-events: none;
+    z-index: 100;
 }