:root {
    --bg-color-light: #f0f2f5;
    --text-color-light: #333;
    --container-bg-light: #fff;
    --primary-color-light: #1a73e8;
    --secondary-text-light: #5f6368;
    --lotto-bg-light: #e8f0fe;
    --lotto-text-light: #1967d2;
    --toggle-bg-light: #ddd;
    --toggle-fg-light: #333;

    --bg-color-dark: #121212;
    --text-color-dark: #e0e0e0;
    --container-bg-dark: #1e1e1e;
    --primary-color-dark: #bb86fc;
    --secondary-text-dark: #b0b0b0;
    --lotto-bg-dark: #332d41;
    --lotto-text-dark: #bb86fc;
    --toggle-bg-dark: #444;
    --toggle-fg-dark: #e0e0e0;
}

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

body.dark-mode {
    background-color: var(--bg-color-dark);
    color: var(--text-color-dark);
}

.container {
    background-color: var(--container-bg-light);
    padding: 40px;
    border-radius: 12px;
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.1);
    text-align: center;
    width: 90%;
    max-width: 500px;
    position: relative;
    transition: background-color 0.3s;
}

body.dark-mode .container {
    background-color: var(--container-bg-dark);
}

.theme-toggle {
    position: absolute;
    top: 20px;
    right: 20px;
}

#theme-toggle-btn {
    background-color: var(--toggle-bg-light);
    color: var(--toggle-fg-light);
    border: none;
    padding: 8px 12px;
    border-radius: 6px;
    cursor: pointer;
    transition: background-color 0.3s, color 0.3s;
}

body.dark-mode #theme-toggle-btn {
    background-color: var(--toggle-bg-dark);
    color: var(--toggle-fg-dark);
}

h1 {
    font-size: 2.5em;
    color: var(--primary-color-light);
    margin-bottom: 10px;
    transition: color 0.3s;
}

body.dark-mode h1 {
    color: var(--primary-color-dark);
}

p {
    font-size: 1.1em;
    color: var(--secondary-text-light);
    margin-bottom: 30px;
    transition: color 0.3s;
}

body.dark-mode p {
    color: var(--secondary-text-dark);
}

#generator-btn {
    background-color: var(--primary-color-light);
    color: white;
    border: none;
    padding: 15px 30px;
    font-size: 1.2em;
    border-radius: 8px;
    cursor: pointer;
    transition: background-color 0.3s, box-shadow 0.3s;
    box-shadow: 0 4px 12px rgba(26, 115, 232, 0.2);
}

body.dark-mode #generator-btn {
    background-color: var(--primary-color-dark);
    box-shadow: 0 4px 12px rgba(187, 134, 252, 0.2);
}

#generator-btn:hover {
    background-color: #1765c4;
    box-shadow: 0 6px 16px rgba(26, 115, 232, 0.3);
}

body.dark-mode #generator-btn:hover {
    background-color: #a059f7;
    box-shadow: 0 6px 16px rgba(187, 134, 252, 0.3);
}

.lotto-numbers {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 15px;
    margin-top: 30px;
}

.lotto-number {
    background-color: var(--lotto-bg-light);
    color: var(--lotto-text-light);
    width: 60px;
    height: 60px;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 1.8em;
    font-weight: bold;
    border-radius: 50%;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
    animation: pop-in 0.5s ease-out forwards;
    transition: background-color 0.3s, color 0.3s;
}

body.dark-mode .lotto-number {
    background-color: var(--lotto-bg-dark);
    color: var(--lotto-text-dark);
}

@keyframes pop-in {
    0% {
        transform: scale(0.5);
        opacity: 0;
    }
    100% {
        transform: scale(1);
        opacity: 1;
    }
}