:root {
    --bg-color: #f0f0f0;
    --text-color: #333;
    --card-bg-color: #fff;
    --ball-bg-color: #eee;
}

body {
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    background-color: var(--bg-color);
    color: var(--text-color);
    font-family: 'Nanum Gothic', sans-serif;
    transition: background-color 0.3s, color 0.3s;
}

body.dark-mode {
    --bg-color: #333;
    --text-color: #f0f0f0;
    --card-bg-color: #444;
    --ball-bg-color: #555;
}

.lotto-card {
    background-color: var(--card-bg-color);
    padding: 2rem;
    border-radius: 1rem;
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.1);
    text-align: center;
}

.lotto-sets {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
    margin: 2rem 0;
}

.theme-toggle-button {
    position: fixed;
    top: 1rem;
    right: 1rem;
    background: none;
    border: 1px solid var(--text-color);
    padding: 0.5rem 1rem;
    border-radius: 0.5rem;
    font-size: 1rem;
    cursor: pointer;
    color: var(--text-color);
}

.lotto-numbers {
    display: flex;
    gap: 1rem;
    justify-content: center;
}

.lotto-button {
    background-color: #2196F3; /* Blue */
    color: white;
    padding: 1rem 2rem;
    border: none;
    border-radius: 0.5rem;
    cursor: pointer;
    font-size: 1rem;
    transition: background-color 0.3s;
}

.lotto-button:hover {
    background-color: #1976D2; /* Darker Blue */
}

lotto-ball {
    display: flex;
    justify-content: center;
    align-items: center;
    width: 3rem;
    height: 3rem;
    border-radius: 50%;
    background-color: var(--ball-bg-color);
    font-size: 1.5rem;
    font-weight: bold;
}