In the past few years, Apple has modernized the macOS interface by increasing transparency, flattening out elements, and adding white space. If you find the new interface difficult to use, try increasing the contrast.
“Increase Contrast” is one of the many accessibility features in macOS. It helps users with low and impaired vision read the computer’s display more easily, but anyone can use the feature to make the interface more legible.
Once enabled, every UI element (whether it’s a just a text box or a button) has a pronounced black border around it. This makes it much easier to locate a button and to know where one section of an app ends, and when another begins.
You can enable this feature from macOS’ System Preferences. Click on the Apple button from the menu bar and then select “System Preferences.”
Next, click on the “Accessibility” button.
From the left sidebar, select the “Display” option.
Here, click on the checkmark next to “Increase Contrast.”
You’ll now see that the entire UI has borders around elements, and, as an added benefit, the transparency effect is gone. When you enable the “Increase Contrast” feature, macOS automatically enables the “Reduce Transparency” option as well.
When you want to disable the feature, head back to the Display section in Accessibility, and click on the checkmark next to the “Increase Contrast” option.