Duolingo 50 Day Streak Goal Checkpoint Reveal Animation

This gamified animation sequence celebrates reaching a 50-day streak checkpoint. It begins with a horizontal timeline where the 50-day card scales up with a bouncy spring effect, transforming into a flaming reward card while shooting out a '+50 gems' text indicator. Simultaneously, the gem counter in the top-right corner increments dynamically using a rolling number ticker. Once the reward is claimed, the 50-day card scales down, the entire timeline slides to the left to center the next milestone (60 days), the subtitle text crossfades to a new prompt, and a primary 'Continue' button slides up from the bottom screen edge.