.theme-preview.theme-classic {
    background: linear-gradient(135deg, var(--primary), var(--secondary));
}

.theme-preview.theme-anniversary {
    background: linear-gradient(135deg, #FFD700, #8A2BE2, #FF69B4);
}

.theme-preview.theme-newyear {
    background: linear-gradient(135deg, #0c1e3e 0%, #1a3a5f 50%, #0c1e3e 100%);
}

.theme-preview.theme-undertale{
    background: black;
    border: white 5px solid;
    border-radius: 0%;
}