fix(grid): fix styles for system theme

Author: nzbin

projects/extensions/grid/grid.scss

@@ -142,7 +142,7 @@ $_tokens: tokens-mtx-grid.$prefix, tokens-mtx-grid.get-token-slots();
   .mtx-grid-checkbox-cell {
     width: 60px;
     min-width: 60px;
-    padding: 0 calc((60px - var(--mdc-checkbox-state-layer-size)) / 2);
+    padding: 0 calc((60px - var(--mdc-checkbox-state-layer-size, 40px)) / 2);
   }
 }
 
@@ -157,7 +157,7 @@ $_tokens: tokens-mtx-grid.$prefix, tokens-mtx-grid.get-token-slots();
   display: flex;
   justify-content: space-between;
   align-items: center;
-  min-height: var(--mat-table-header-container-height);
+  min-height: var(--mat-table-header-container-height, 56px);
   padding: 8px;
   box-sizing: border-box;
 
@@ -208,7 +208,7 @@ $_tokens: tokens-mtx-grid.$prefix, tokens-mtx-grid.get-token-slots();
 .mtx-grid-statusbar {
   display: flex;
   align-items: center;
-  min-height: var(--mat-table-header-container-height);
+  min-height: var(--mat-table-header-container-height, 56px);
   padding: 8px;
   box-sizing: border-box;
 
@@ -231,9 +231,8 @@ $_tokens: tokens-mtx-grid.$prefix, tokens-mtx-grid.get-token-slots();
   display: inline-block;
   vertical-align: middle;
 
-
   @include token-utils.use-tokens($_tokens...) {
-    $compat-size: token-utils.get-token-variable(row-expand-button-size);
+    $compat-size: token-utils.get-token-variable(row-expand-button-size, 40px);
 
     width: var(--mdc-icon-button-state-layer-size, $compat-size);
     height: var(--mdc-icon-button-state-layer-size, $compat-size);
@@ -243,7 +242,7 @@ $_tokens: tokens-mtx-grid.$prefix, tokens-mtx-grid.get-token-slots();
 .mtx-grid-expansion-detail {
   display: flex;
   align-items: center;
-  min-height: var(--mat-table-row-item-container-height);
+  min-height: var(--mat-table-row-item-container-height, 52px);
   overflow: hidden;
 }