:root {
    --main-bg-color: #f0f0f0;
    --container-bg-color: #ffffff;
    --primary-color: #4a90e2;
    --secondary-color: #50e3c2;
    --text-color: #333333;
    --white-color: #ffffff;
    --shadow-color: rgba(0, 0, 0, 0.1);
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    background-color: var(--main-bg-color);
    color: var(--text-color);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    min-height: 100vh;
    margin: 0;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='300' height='300'%3E%3Crect width='100%25' height='100%25' fill='transparent' /%3E%3Ctext x='10' y='30' font-size='20' fill='rgba(128,128,128,0.2)'%3E3%3C/text%3E%3Ctext x='50' y='80' font-size='25' fill='rgba(128,128,128,0.2)'%3E7%3C/text%3E%3Ctext x='100' y='50' font-size='15' fill='rgba(128,128,128,0.2)'%3E1%3C/text%3E%3Ctext x='150' y='120' font-size='30' fill='rgba(128,128,128,0.2)'%3E9%3C/text%3E%3Ctext x='20' y='150' font-size='22' fill='rgba(128,128,128,0.2)'%3E5%3C/text%3E%3Ctext x='180' y='180' font-size='18' fill='rgba(128,128,128,0.2)'%3E2%3C/text%3E%3Ctext x='80' y='180' font-size='28' fill='rgba(128,128,128,0.2)'%3E4%3C/text%3E%3Ctext x='250' y='90' font-size='16' fill='rgba(128,128,128,0.2)'%3E8%3C/text%3E%3Ctext x='220' y='250' font-size='24' fill='rgba(128,128,128,0.2)'%3E6%3C/text%3E%3Ctext x='30' y='250' font-size='19' fill='rgba(128,128,128,0.2)'%3E0%3C/text%3E%3C/svg%3E"), linear-gradient(45deg, var(--primary-color), var(--secondary-color));
}

header, footer {
    text-align: center;
    color: var(--white-color);
    text-shadow: 0 2px 4px var(--shadow-color);
}

header h1 {
    font-size: 3rem;
    margin-bottom: 1rem;
}

main {
    width: 90%;
    max-width: 600px;
}

.lotto-container {
    background-color: var(--container-bg-color);
    padding: 2rem;
    border-radius: 15px;
    box-shadow: 0 10px 30px var(--shadow-color);
    text-align: center;
}

#lotto-balls-container {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 1rem;
    margin-bottom: 2rem;
    min-height: 100px;
}

#generate-btn {
    background-image: linear-gradient(45deg, var(--primary-color), var(--secondary-color));
    color: var(--white-color);
    border: none;
    padding: 1rem 2rem;
    font-size: 1.2rem;
    border-radius: 50px;
    cursor: pointer;
    transition: transform 0.2s, box-shadow 0.2s;
    box-shadow: 0 4px 15px var(--shadow-color);
}

#generate-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px var(--shadow-color);
}

lotto-ball {
    --ball-size: 60px;
    width: var(--ball-size);
    height: var(--ball-size);
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    font-size: 1.5rem;
    font-weight: bold;
    color: var(--white-color);
    box-shadow: 0 4px 10px rgba(0, 0, 0, 0.2);
    animation: appear 0.5s ease-in-out;
}

@keyframes appear {
    from {
        transform: scale(0);
        opacity: 0;
    }
    to {
        transform: scale(1);
        opacity: 1;
    }
}

[data-theme="dark"] {
    --main-bg-color: #121212;
    --container-bg-color: #1e1e1e;
    --text-color: #e0e0e0;
    --shadow-color: rgba(255, 255, 255, 0.1);
}