ClassicLockScreen is a brand new jailbreak tweak that debuted on Cydia recently and allows you to replace the current Lock screen style on iOS 7 with one of the four different styles supplied by the tweak.
The tweak offers four different Lock screen styles: classic, ‘Modern Mode’, ‘Dark Mode’ and ‘7.1 Slider Style’. The classic mode ports the exact iOS 6 Lock screen style to iOS 7 and brings back the iOS 6 media control buttons, lock keypad as well as the unlock sound. The Modern and Dark modes feature a stylish ‘Slide to Unlock’ slider with a blur background and top bar. The difference between the two styles is that the latter sports a darker look.