# Sandbox.UI.Panel.FlashClass

```csharp
void FlashClass(string classname, float seconds)
```

Add a class for a set amount of seconds. If called multiple times, we will stomp the earlier call.

### Parameters

- `classname` (`string`)
- `seconds` (`float`)

Declared in [Sandbox.UI.Panel](/api/Sandbox.UI.Panel).
Assembly: `Sandbox.Engine`.