body {
    background: linear-gradient(135deg, #f3f4f6, #e5e7eb);
    min-height: 100vh;
}

.container {
    max-width: 800px;
    margin: 0 auto;
    padding: 1rem;
}

select, button {
    transition: all 0.3s ease;
}

select:focus, button:focus {
    outline: none;
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.5);
}

#output {
    max-height: 500px;
    overflow-y: auto;
    scrollbar-width: thin;
}

#output::-webkit-scrollbar {
    width: 8px;
}

#output::-webkit-scrollbar-track {
    background: #f1f1f1;
}

#output::-webkit-scrollbar-thumb {
    background: #888;
    border-radius: 4px;
}

#output::-webkit-scrollbar-thumb:hover {
    background: #555;
}

@media (max-width: 640px) {
    .container {
        padding: 0.5rem;
    }

    h1 {
        font-size: 1.5rem;
    }

    select, button {
        font-size: 0.9rem;
        padding: 0.5rem;
    }
}