As the band progressed, they incorporated more elements of pop and AOR into their sound. Their most successful album, "Hysteria" (1987), is a prime example of this, with its catchy hooks, soaring choruses, and polished production. The album spawned several hit singles, including "Pour Some Sugar on Me", "Animal", and "Love Bites".
Def Leppard continued to explore different styles in their subsequent albums, such as "Adrenalize" (1992) and "Slang" (1996), but their overall sound remained rooted in hard rock. They have also released several live albums and compilation albums over the years.
In recent years, Def Leppard has returned to their classic hard rock sound, as evidenced by their 2015 album, "Def Leppard". The album was met with positive reviews from critics and fans, and it showcased the band's enduring musical legacy.
Overall, Def Leppard's music can be described as hard rock, with elements of pop, heavy metal, and AOR. Their music is known for its catchy melodies, powerful vocals, and guitar-driven sound.