fix: remove shadow for bordered main container (#7655)

fix PD-1498

packages/frontend/core/src/components/workspace/index.css.ts

@@ -56,9 +56,6 @@ export const mainContainerStyle = style({
       borderRadius: 6,
       margin: '8px',
       overflow: 'clip',
-      // TODO(@Peng): is this performance intensive?
-      // TODO(@catsjuice): not match with design's shadow, theme missing
-      filter: 'drop-shadow(0px 0px 4px rgba(66,65,73,.14))',
       '@media': {
         print: {
           overflow: 'visible',

packages/frontend/core/src/modules/workbench/view/split-view/split-view.css.ts

@@ -43,11 +43,14 @@ export const splitViewPanel = style({
     },
     '[data-client-border="false"] &:not([data-is-last="true"]):not([data-is-dragging="true"])':
       {
-        borderRight: `1px solid ${cssVar('borderColor')}`,
+        borderRight: `0.5px solid ${cssVar('borderColor')}`,
       },
     '&[data-is-dragging="true"]': {
       zIndex: 1,
     },
+    '[data-client-border="true"] &': {
+      border: `0.5px solid ${cssVar('borderColor')}`,
+    },
   },
 });