:root {
    --primary-color: #4a90e2;
    --secondary-color: #ff8c00;
    --background-color: #f0f4f8;
    --card-background: #ffffff;
    --text-color: #333333;
    --white-color: #ffffff;
    --shadow-color: rgba(0, 0, 0, 0.1);
}

[data-theme="dark"] {
    --background-color: #121212;
    --card-background: #1e1e1e;
    --text-color: #e0e0e0;
    --shadow-color: rgba(0, 0, 0, 0.5);
    --primary-color: #6ab0ff;
}

body {
    font-family: 'Arial', sans-serif;
    background-color: var(--background-color);
    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;
    position: relative;
}

.theme-toggle {
    position: absolute;
    top: -40px;
    right: 0;
}

#theme-btn {
    background: none;
    border: none;
    color: var(--text-color);
    font-size: 1.5rem;
    cursor: pointer;
    transition: color 0.3s;
}

header h1 {
    font-size: 2.5rem;
    color: var(--primary-color);
    margin-bottom: 2rem;
}

.lotto-card {
    background-color: var(--card-background);
    padding: 2rem;
    border-radius: 15px;
    box-shadow: 0 10px 20px var(--shadow-color);
    transition: background-color 0.3s, box-shadow 0.3s;
}

.numbers-container {
    display: flex;
    justify-content: center;
    gap: 1rem;
    margin-bottom: 2rem;
}

.number {
    display: flex;
    justify-content: center;
    align-items: center;
    width: 50px;
    height: 50px;
    border-radius: 50%;
    background-color: var(--secondary-color);
    color: var(--white-color);
    font-size: 1.5rem;
    font-weight: bold;
}

#generate-btn {
    background-color: var(--primary-color);
    color: var(--white-color);
    border: none;
    padding: 1rem 2rem;
    font-size: 1.2rem;
    border-radius: 10px;
    cursor: pointer;
    transition: background-color 0.3s ease;
    box-shadow: 0 4px 6px var(--shadow-color);
}

#generate-btn:hover {
    background-color: #357abd;
}