[BUG]: Calendar picker icon has poor visibility in Dark Mode for date inputs

[jikrana1]

Bug Description

The native calendar picker icon inside the Start Date and End Date input fields is barely visible when the application is used in Dark Mode.

The low contrast between the calendar icon and the dark input background makes it difficult for users to notice and use the date picker.

The same fields display correctly in Light Mode, indicating that the issue is specific to the dark theme.

Expected Behavior

The calendar picker icon should remain clearly visible and accessible in both Light and Dark themes.

Actual Behavior

In Dark Mode, the calendar picker icon has very low visibility, making it difficult to identify and interact with the date picker.

Steps to Reproduce

1. Open OrgExplorer.
2. Switch the application to Dark Mode.
3. Navigate to Contributors.
4. Open any contributor profile.
5. Locate the Reporting Window & Date Presets section.
6. Observe the Start Date and End Date input fields.
7. Notice that the calendar picker icon is barely visible.

Logs and Screenshots

Dark Mode

Light Mode

Environment Details

No response

Impact

Low - Minor inconvenience

Code of Conduct

• I have joined the Discord server and will post updates there
• I have searched existing issues to avoid duplicates

I would like to work on this issue. If it looks valid, could you assign it to me?