Reduce center size and fix jitter

style.css

@@ -404,7 +404,7 @@
   left: 50%;
   width: calc(var(--clock-size) * 0.15);
   height: calc(var(--clock-size) * 0.15);
-  transform: translate(-50%, -50%);
+  transform: translate(-50%, -50%) translateZ(0);
   background: url('logo.svg') center/contain no-repeat;
   background-color: #ffffff;
   border-radius: 50%;
@@ -413,6 +413,13 @@
   pointer-events: none;
 }
 
+@media screen and (min-width: 1200px) {
+  .clock-center {
+    width: calc(var(--clock-size) * 0.105);
+    height: calc(var(--clock-size) * 0.105);
+  }
+}
+
 .clock-label {
   position: absolute;
   bottom: 30%;