[Improvement][UI] Optimize task disable node style in dark theme (#14871)

Co-authored-by: 旺阳 <qingwli@cisco.com>

dolphinscheduler-ui/src/views/projects/workflow/components/dag/use-custom-cell-builder.ts

@@ -103,7 +103,7 @@ export function useCustomCellBuilder() {
           text: truncation
         },
         rect: {
-          fill: flag === 'NO' ? '#f3f3f5' : '#ffffff'
+          fill: flag === 'NO' ? 'var(--custom-disable-bg)' : '#ffffff'
         }
       }
     }

dolphinscheduler-ui/src/views/projects/workflow/components/dag/use-task-edit.ts

@@ -170,7 +170,7 @@ export function useTaskEdit(options: Options) {
           setNodeName(task.code + '', taskDef.name)
           let fillColor = '#ffffff'
           if (task.flag === 'YES') {
-            fillColor = '#f3f3f5'
+            fillColor = 'var(--custom-disable-bg)'
           }
           setNodeFillColor(task.code + '', fillColor)
 

dolphinscheduler-ui/src/views/projects/workflow/components/dag/x6-style.scss

@@ -32,3 +32,11 @@ $BG_WHITE: #ffffff;
     }
   }
 }
+
+[class*="dag-light"] {
+  --custom-disable-bg: #f3f3f5
+}
+
+[class*="dag-dark"] {
+  --custom-disable-bg: #d3d3d3
+}