update import steps design (#12463)

closes https://github.com/twentyhq/core-team-issues/issues/916

![Screenshot 2025-06-05 at 10 52
58](https://github.com/user-attachments/assets/ba5b6d65-0c1f-4d63-a197-e61816ec2d55)
![Screenshot 2025-06-05 at 10 53
09](https://github.com/user-attachments/assets/4aed579e-5e0e-4570-9518-b6e8ac604ea6)
![Screenshot 2025-06-05 at 10 53
24](https://github.com/user-attachments/assets/6f716306-ba08-468c-875a-4279991c1abd)

packages/twenty-front/src/modules/spreadsheet-import/components/SpreadsheetImportTable.tsx

@@ -28,18 +28,17 @@ const StyledDataGrid = styled(DataGrid)`
   --row-selected-hover-background-color: ${({ theme }) =>
     theme.background.secondary};
 
+  border: none;
   block-size: 100%;
-  border: 1px solid ${({ theme }) => theme.border.color.medium};
-  border-radius: ${({ theme }) => theme.border.radius.md};
   width: 100%;
 
   .rdg-header-row .rdg-cell {
     box-shadow: none;
     color: ${({ theme }) => theme.font.color.tertiary};
+    background-color: ${({ theme }) => theme.background.secondary};
     font-size: ${({ theme }) => theme.font.size.sm};
     font-weight: ${({ theme }) => theme.font.weight.semiBold};
     letter-spacing: wider;
-    text-transform: uppercase;
     ${({ headerRowHeight }) => {
       if (headerRowHeight === 0) {
         return `
@@ -68,7 +67,7 @@ const StyledDataGrid = styled(DataGrid)`
   }
 
   .rdg-cell-error {
-    background-color: ${({ theme }) => RGBA(theme.color.red, 0.08)};
+    background-color: ${({ theme }) => theme.adaptiveColors.yellow1};
   }
 
   .rdg-cell-warning {
@@ -134,7 +133,7 @@ export const SpreadsheetImportTable = <Data,>({
   return (
     <StyledDataGrid
       direction={rtl ? 'rtl' : 'ltr'}
-      rowHeight={52}
+      rowHeight={40}
       {...{
         className: `${className || ''} ${themeClassName}`,
         columns,