Conditional market pop up is partially shown

**Description:**
When clicking the question mark, the pop up displayed is partially shown, and it's difficult to close it, because the closing cross is hidden.

**Steps to reproduce:**
1. Go to https://conditionaltokens.staging.gnosisdev.com/#
2. Click the question mark placed next to "conditional"
3. Observe

**Enviorment:**
Browser: Google Chrome
Wallet: Metamask
Computer: Dell Vostro 5100 14 inches

**Capture:**
https://drive.google.com/open?id=1FXfXSrGZzd4zLpj2S44FDSDJnenlPyda