:root {
    --main-bg-color: #f0f0f0;
    --container-bg-color: #ffffff;
    --text-color: #333333;
    --number-bg-color: #4CAF50;
    --number-text-color: #ffffff;
    --button-bg-color: #008CBA;
    --button-text-color: #ffffff;
    --shadow-color: rgba(0, 0, 0, 0.1);
    --toggle-bg: #dddddd;
}

body.dark-mode {
    --main-bg-color: #121212;
    --container-bg-color: #1e1e1e;
    --text-color: #f0f0f0;
    --number-bg-color: #81c784;
    --number-text-color: #121212;
    --button-bg-color: #4fc3f7;
    --button-text-color: #121212;
    --shadow-color: rgba(0, 0, 0, 0.5);
    --toggle-bg: #333333;
}

body {
    font-family: 'Helvetica Neue', sans-serif;
    background-color: var(--main-bg-color);
    color: var(--text-color);
    background-image: linear-gradient(45deg, rgba(255, 255, 255, 0.02) 25%, transparent 25%, transparent 50%, rgba(255, 255, 255, 0.02) 50%, rgba(255, 255, 255, 0.02) 75%, transparent 75%, transparent);
    background-size: 50px 50px;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    margin: 0;
    transition: background-color 0.3s ease, color 0.3s ease;
}

.container {
    background-color: var(--container-bg-color);
    padding: 2rem;
    border-radius: 15px;
    box-shadow: 0 10px 20px var(--shadow-color), 0 6px 6px var(--shadow-color);
    text-align: center;
    max-width: 90%;
    transition: background-color 0.3s ease, box-shadow 0.3s ease;
}

h1 {
    font-size: clamp(1.5rem, 5vw, 2.5rem);
    margin-bottom: 2rem;
    color: var(--text-color);
}

.theme-toggle {
    position: fixed;
    top: 20px;
    right: 20px;
    background-color: var(--toggle-bg);
    border: none;
    padding: 10px 15px;
    border-radius: 20px;
    cursor: pointer;
    font-size: 1rem;
    color: var(--text-color);
    box-shadow: 0 2px 5px var(--shadow-color);
    transition: all 0.3s ease;
}

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

.number {
    width: 60px;
    height: 60px;
    background-color: var(--number-bg-color);
    color: var(--number-text-color);
    font-size: 1.5rem;
    font-weight: bold;
    display: flex;
    justify-content: center;
    align-items: center;
    border-radius: 50%;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
    transition: transform 0.3s ease, background-color 0.3s ease;
}

.generate-btn {
    background-color: var(--button-bg-color);
    color: var(--button-text-color);
    border: none;
    padding: 1rem 2rem;
    font-size: 1.2rem;
    border-radius: 10px;
    cursor: pointer;
    box-shadow: 0 5px 15px rgba(0, 140, 186, 0.4);
    transition: background-color 0.3s ease, box-shadow 0.3s ease, transform 0.2s ease;
}

.generate-btn:hover, .generate-btn:focus {
    background-color: #005f73;
    box-shadow: 0 8px 25px rgba(0, 140, 186, 0.6);
    transform: translateY(-2px);
}

.generate-btn:active {
    transform: translateY(1px);
}

@media (max-width: 600px) {
    .container {
        padding: 1.5rem;
    }
    .number {
        width: 50px;
        height: 50px;
        font-size: 1.2rem;
    }
    .generate-btn {
        padding: 0.8rem 1.5rem;
        font-size: 1rem;
    }
}