:root {
    --background-color: #1a1a2e;
    --card-color: #16213e;
    --primary-color: #0f3460;
    --secondary-color: #e94560;
    --font-color: #ffffff;
    --star-empty-color: #535353;
    --star-full-color: #ffc700;
}

body.light-mode {
    --background-color: #f0f2f5;
    --card-color: #ffffff;
    --primary-color: #007bff;
    --secondary-color: #28a745;
    --font-color: #333333;
    --star-empty-color: #cccccc;
    --star-full-color: #ffcc00;
}

body {
    margin: 0;
    padding: 0;
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
    background: url('https://images.unsplash.com/photo-1534796636912-3b95b3ab5986?q=80&w=2071&auto=format&fit=crop&ixlib=rb-4.0.3&ixid=M3wxMjA3fDB8MHxwaG90by1wYWdlfHx8fGVufDB8fHx8fA%3D%3D') no-repeat center center fixed;
    background-size: cover;
    color: var(--font-color);
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    transition: background-color 0.3s ease, color 0.3s ease;
}

body.light-mode {
    background: url('https://images.unsplash.com/photo-1517486804603-f32b13ed8d76?q=80&w=2070&auto=format&fit=crop&ixlib=rb-4.0.3&ixid=M3wxMjA3fDB8MHxwaG90by1wYWdlfHx8fGVufDB8fHx8fA%3D%3D') no-repeat center center fixed;
    background-size: cover;
}

.theme-toggle {
    position: absolute;
    top: 20px;
    right: 20px;
    background-color: var(--card-color);
    color: var(--font-color);
    border: 1px solid var(--primary-color);
    padding: 10px 15px;
    border-radius: 5px;
    cursor: pointer;
    font-size: 1.5rem;
    z-index: 1000;
    transition: background-color 0.3s ease, color 0.3s ease, border-color 0.3s ease;
}

.theme-toggle:hover {
    filter: brightness(1.2);
}