:root {
    --bg-color: #f0f2f5;
    --bg-image: url("data:image/svg+xml,%3Csvg width='6' height='6' viewBox='0 0 6 6' xmlns='http://www.w3.org/2000/svg'%3E%3Cg fill='%239C92AC' fill-opacity='0.1'%3E%3Cpath d='M5 0h1L0 6V5zM6 5v1H5z'/%3E%3C/g%3E%3C/svg%3E");
    --container-bg: white;
    --text-color: #333;
    --lotto-number-bg: #f0f2f5;
    --lotto-number-color: #333;
    --box-shadow-light: rgba(0,0,0,0.1);
    --box-shadow-dark: rgba(0,0,0,0.15);
}

body.dark-mode {
    --bg-color: #2c3e50;
    --bg-image: url("data:image/svg+xml,%3Csvg width='6' height='6' viewBox='0 0 6 6' xmlns='http://www.w3.org/2000/svg'%3E%3Cg fill='%2334495e' fill-opacity='0.1'%3E%3Cpath d='M5 0h1L0 6V5zM6 5v1H5z'/%3E%3C/g%3E%3C/svg%3E");
    --container-bg: #34495e;
    --text-color: #ecf0f1;
    --lotto-number-bg: #2c3e50;
    --lotto-number-color: #ecf0f1;
    --box-shadow-light: rgba(255,255,255,0.1);
    --box-shadow-dark: rgba(255,255,255,0.15);
}

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

.container {
    text-align: center;
    background: var(--container-bg);
    padding: 40px;
    border-radius: 15px;
    box-shadow: 0 10px 20px var(--box-shadow-light), 0 6px 6px var(--box-shadow-dark);
    transition: background 0.3s ease, box-shadow 0.3s ease;
}

h1 {
    color: var(--text-color);
    margin-bottom: 20px;
    transition: color 0.3s ease;
}

#theme-toggle {
    background: none;
    border: none;
    font-size: 24px;
    cursor: pointer;
    position: absolute;
    top: 20px;
    right: 20px;
    padding: 10px;
    border-radius: 50%;
    transition: background-color 0.3s ease;
}

#theme-toggle:hover {
    background-color: rgba(0, 0, 0, 0.1);
}

body.dark-mode #theme-toggle:hover {
    background-color: rgba(255, 255, 255, 0.1);
}

#generate-btn {
    background-color: #4CAF50;
    color: white;
    padding: 15px 32px;
    text-align: center;
    text-decoration: none;
    display: inline-block;
    font-size: 16px;
    margin: 4px 2px;
    cursor: pointer;
    border: none;
    border-radius: 8px;
    transition: all 0.3s ease;
    box-shadow: 0 4px 15px rgba(76, 175, 80, 0.4);
}

#generate-btn:hover {
    background-color: #45a049;
    box-shadow: 0 6px 20px rgba(76, 175, 80, 0.6);
    transform: translateY(-2px);
}

.menu-display {
    font-size: 2em;
    font-weight: bold;
    color: var(--text-color);
    margin-bottom: 20px;
    min-height: 1.5em; /* Ensure space even when empty */
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 10px;
    border-radius: 8px;
    border: 2px dashed var(--box-shadow-light);
    transition: color 0.3s ease, border-color 0.3s ease;
}