A heartwarming Christmas-themed mobile wallpaper showing Santa Claus standing on a wooden ladder, placing a glowing golden star atop a decorated Christmas tree. The tree is adorned with red, gold, and white ornaments, and wrapped in strings of warm lights. Snow gently falls in the background, creating a serene wintry atmosphere. The scene is joyful and traditional, with a cozy holiday spirit and high-resolution detail, perfectly framed for vertical mobile display.