:root {
    --primary-color: #2c3e50;
    --secondary-color: #3498db;
    --background-color: #ecf0f1;
    --container-bg: #ffffff;
    --text-color: #2c3e50;
    --font-family: 'Montserrat', sans-serif;
}

[data-theme='dark'] {
    --primary-color: #ecf0f1;
    --secondary-color: #3498db;
    --background-color: #2c3e50;
    --container-bg: #34495e;
    --text-color: #ecf0f1;
}

body {
    font-family: var(--font-family);
    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 ease, color 0.3s ease;
}

.container {
    position: relative;
    text-align: center;
    background-color: var(--container-bg);
    padding: 40px;
    border-radius: 10px;
    box-shadow: 0 10px 20px rgba(0,0,0,0.19), 0 6px 6px rgba(0,0,0,0.23);
    transition: background-color 0.3s ease;
}

#theme-toggle {
    position: absolute;
    top: 10px;
    right: 10px;
    background: none;
    border: none;
    font-size: 24px;
    cursor: pointer;
    padding: 5px;
}

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

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

.lotto-number {
    width: 50px;
    height: 50px;
    background-color: var(--secondary-color);
    color: white;
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 24px;
    margin: 0 10px;
    animation: pop-in 0.5s ease-out forwards;
}

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

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

#generate-btn:hover {
    filter: brightness(1.1);
}