:root {
    --body-bg: #f0f2f5;
    --container-bg: #fff;
    --text-color: #333;
    --primary-btn-bg: #4CAF50;
    --primary-btn-hover-bg: #45a049;
    --secondary-btn-bg: #008CBA;
    --btn-text-color: white;
    --container-shadow: 0 4px 8px rgba(0,0,0,0.1);
}

body[data-theme='dark'] {
    --body-bg: #1a1a1a;
    --container-bg: #2b2b2b;
    --text-color: #f0f2f5;
    --primary-btn-bg: #4CAF50;
    --primary-btn-hover-bg: #45a049;
    --secondary-btn-bg: #555;
    --btn-text-color: white;
    --container-shadow: 0 4px 8px rgba(0,0,0,0.4);
}

body {
    font-family: 'Arial', sans-serif;
    background-color: var(--body-bg);
    color: var(--text-color);
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    margin: 0;
    transition: background-color 0.3s, color 0.3s;
}

.container {
    text-align: center;
    background-color: var(--container-bg);
    padding: 40px;
    border-radius: 10px;
    box-shadow: var(--container-shadow);
    transition: background-color 0.3s;
}

h1 {
    color: var(--text-color);
    margin-bottom: 20px;
}

#generate-btn, #theme-toggle-btn {
    color: var(--btn-text-color);
    padding: 15px 25px;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    font-size: 16px;
    transition: background-color 0.3s;
    margin: 10px 5px;
}

#generate-btn {
    background-color: var(--primary-btn-bg);
}

#generate-btn:hover {
    background-color: var(--primary-btn-hover-bg);
}

#theme-toggle-btn {
    background-color: var(--secondary-btn-bg);
}

#theme-toggle-btn:hover {
    opacity: 0.9;
}

.lotto-numbers-container {
    display: flex;
    justify-content: center;
    margin-top: 30px;
}

lotto-ball {
    margin: 0 5px;
}