Opacity is the extent to which something blocks light. Crater Editor provides an Opacity Effect so that you can adjust the degree of transparency of elements.

To change the opacity, follow these steps:

1. Select the element and expand the Effects from the right toolbar.

2. Choose the Opacity effect.

3. Adjust the opacity level to get the look you want.

4. In case you uncheck the Display checkbox, you'll hide the effect and the element will receive its original look. You can check the Display box later to use the effect.

5. To remove the effect, click the Delete icon.

6. Make sure to save the page when you're done.