The Style page of the KDE Control Center allows you to determine the visual style of window components (called “widgets”) such as buttons, sliders, tabs, the Title Bar and so on. There are several nice styles available, and some that – in my opinion, anyway – are not so wonderful.
Click on the Selection Bar to choose a different style. Then you can make some other minor modifications to each style.
The tabs on this page allow you to activate various icon and Toolbar animation effects. These can be fun and serve to impress your friends, but you may want to disable them on older, less powerful computers, as they take memory and CPU cycles. Both resources are in short supply on many of those older computers. Use your own judgement, but I do like to play with these and change them from time to time as you can see by the array of styles in the figures for this book.