:root {
    --bg-color: #f0f2f5;
    --container-bg: #fff;
    --text-color: #333;
    --primary-color: #4a90e2;
    --secondary-color: #357abD;
    --button-text: #fff;
    --shadow-color: rgba(0,0,0,0.1);
}

.dark-mode {
    --bg-color: #1a1a1a;
    --container-bg: #2d2d2d;
    --text-color: #f0f2f5;
    --shadow-color: rgba(0,0,0,0.5);
}

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

.container {
    position: relative;
    text-align: center;
    background-color: var(--container-bg);
    padding: 60px 40px 40px;
    border-radius: 10px;
    box-shadow: 0 4px 8px var(--shadow-color);
    transition: background-color 0.3s ease, box-shadow 0.3s ease;
}

.theme-toggle-btn {
    position: absolute;
    top: 15px;
    right: 15px;
    padding: 8px 15px;
    border: 1px solid var(--primary-color);
    border-radius: 20px;
    background: transparent;
    color: var(--primary-color);
    cursor: pointer;
    font-size: 14px;
    transition: all 0.3s ease;
}

.theme-toggle-btn:hover {
    background-color: var(--primary-color);
    color: var(--button-text);
}

h1 {
    margin-bottom: 30px;
    color: var(--text-color);
}

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

.number {
    display: flex;
    justify-content: center;
    align-items: center;
    width: 50px;
    height: 50px;
    margin: 0 5px;
    border-radius: 50%;
    background-color: var(--primary-color);
    color: var(--button-text);
    font-size: 24px;
    font-weight: bold;
}

#generate-btn {
    padding: 15px 30px;
    border: none;
    border-radius: 5px;
    background-color: var(--primary-color);
    color: var(--button-text);
    font-size: 18px;
    cursor: pointer;
    transition: background-color 0.3s ease;
}

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