What you can see is simply your VPS in "High Contrast Mode".
There is nothing wrong with the VPS or the system, it's just a setting that you can change by yourself:
1. You want to click on "Send CtrlAltDel" on the upper right corner of the Website.
2. You want to click on the "Settings" symbol on the lower left.
3. You click the switch for "High Contrast" to disable it.
4. Go back to your MT4, if you still see some weird colors, just close the MT4 once and open it again.