Доработки

src/diagram.css

@@ -181,26 +181,23 @@
   position: relative;
   width: 100%;
   height: 100%;
+  display: flex;
+  align-items: center;
+  justify-content: center;
 }
 
-/*
- * Inset to 1/sqrt(2) of the outer box and rotated 45deg: the diamond's tips
- * exactly reach the outer box's edges without the corners clipping outside it.
- */
-.diagram-node--diamond {
+/* Diamond via clip-path on an unrotated box — see the comment in nodes.tsx for why. */
+.diagram-node--diamond-bg {
   position: absolute;
-  top: 50%;
-  left: 50%;
-  width: 70.71%;
-  height: 70.71%;
-  padding: 0;
-  border-radius: 4px;
-  transform: translate(-50%, -50%) rotate(45deg);
+  inset: 0;
+  border: 1px solid #555;
+  box-sizing: border-box;
+  clip-path: polygon(50% 0%, 100% 50%, 50% 100%, 0% 50%);
 }
 
 .diagram-node__icon {
+  position: relative;
   display: inline-block;
-  transform: rotate(-45deg);
   font-size: 18px;
   font-weight: 700;
   line-height: 1;