:root {
    --bg-color: #f0f0f0;
    --text-color: #333;
    --header-bg: transparent;
    --card-shadow: rgba(0,0,0,0.2);
}

body.dark-mode {
    --bg-color: #1a1a1a;
    --text-color: #f0f0f0;
    --card-shadow: rgba(255,255,255,0.1);
}

body {
    font-family: sans-serif;
    display: flex;
    flex-direction: column;
    align-items: center;
    background-color: var(--bg-color);
    color: var(--text-color);
    transition: background-color 0.3s, color 0.3s;
}

header {
    margin: 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    width: 100%;
    max-width: 600px;
}

#theme-toggle {
    padding: 10px 20px;
    cursor: pointer;
    border-radius: 20px;
    border: 1px solid var(--text-color);
    background: transparent;
    color: var(--text-color);
    font-weight: bold;
    transition: all 0.3s;
}

#theme-toggle:hover {
    background: var(--text-color);
    color: var(--bg-color);
}

main {
    display: flex;
    flex-direction: column;
    align-items: center;
}

#lotto-balls-container {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    margin-bottom: 20px;
}

#generate-button {
    padding: 15px 30px;
    font-size: 1.2em;
    border: none;
    border-radius: 8px;
    background-color: #4CAF50;
    color: white;
    cursor: pointer;
    box-shadow: 0 4px 8px var(--card-shadow);
    transition: background-color 0.3s, transform 0.2s;
}

#generate-button:hover {
    background-color: #45a049;
    transform: translateY(-2px);
}

#generate-button:active {
    transform: translateY(1px);
}