If you want to darken an object in Illustrator, there are a few different ways to do it. One way is to use the Blending Options dialog box. To open the Blending Options dialog box, go to the Illustrator menu and choose Blending Options. To darken an object using the Blending Options dialog box, first make sure that the Transparency option is set to Opaque. Then select the Darken option from the Blend Mode drop-down list and enter a value in the Darkening Amount field. You can also adjust other blending options, such as Opacity and Colorfulness, if you want to change the overall effect of your darkening. ..
