chore(svelte): use correct css var names for defaults

packages/svelte/src/lib/components/BaseEdge/BaseEdge.svelte

@@ -55,12 +55,12 @@
   }
 
   .svelte-flow__edge-path {
-    stroke: var(--edge-color);
+    stroke: var(--edge-color, var(--edge-color-default));
     stroke-width: 1;
   }
 
   :global(.selected) .svelte-flow__edge-path {
-    stroke: var(--edge-color-selected);
+    stroke: var(--edge-color-selected, var(--edge-color-selected-default));
   }
 
   :global(.animated) .svelte-flow__edge-path {

packages/svelte/src/lib/components/ConnectionLine/ConnectionLine.svelte

@@ -32,7 +32,7 @@
 
   .svelte-flow__edge-path,
   .svelte-flow__connection-path {
-    stroke: var(--connection-line-color);
+    stroke: var(--connection-line-color, var(--connection-line-color-default));
     stroke-width: 1;
     fill: none;
   }

packages/svelte/src/lib/components/Handle/Handle.svelte

@@ -108,8 +108,8 @@
     min-height: 5px;
     width: 6px;
     height: 6px;
-    background: var(--handle-background-color);
-    border: 1px solid var(--handle-border-color);
+    background: var(--handle-background-color, var(--handle-background-color-default));
+    border: 1px solid var(--handle-border-color, var(--handle-border-color-default));
     border-radius: 100%;
   }
 

packages/svelte/src/lib/components/NodeWrapper/NodeWrapper.svelte

@@ -86,7 +86,6 @@
   bind:this={nodeRef}
   data-id={id}
   class={cc(['svelte-flow__node', `svelte-flow__node-${type || 'default'}`, className])}
-  class:initializing={!width && !height}
   class:dragging
   class:selected
   class:draggable
@@ -122,12 +121,12 @@
 <style>
   .svelte-flow__node {
     border-radius: 3px;
-    color: var(--node-color);
+    color: var(--node-color, var(--node-color-default));
     text-align: center;
     border-width: 1px;
     border-style: solid;
-    border-color: var(--node-border-color);
-    background-color: var(--node-background-color);
+    border-color: var(--node-border-color, var(--node-border-color-default));
+    background-color: var(--node-background-color, var(--node-background-color-default));
     position: absolute;
     pointer-events: none;
     user-select: none;
@@ -140,14 +139,11 @@
 
   .selected {
     outline: none;
-    box-shadow: 0 0 0 0.5px var(--node-shadow-color-selected);
+    box-shadow: 0 0 0 0.5px
+      var(--node-shadow-color-selected, var(--node-shadow-color-selected-default));
   }
 
   .dragging {
     cursor: grabbing;
   }
-
-  .initializing {
-    visibility: hidden;
-  }
 </style>