/* Day 11 - Dark mode toggle */
body {
    font-family: sans-serif;
    background-color: white;
    color: #333;
    transition: background-color 0.3s, color 0.3s; /* Smooth fade */
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    margin: 0;
}

button {
    padding: 10px 20px;
    font-size: 1.2rem;
    cursor: pointer;
    background-color: #333;
    color: white;
    border: none;
    border-radius: 5px;
}

.dark-mode {
    background-color: #1a1a1a;
    color: #f0f0f0;
}

.dark-mode button {
    background-color: #f0f0f0;
    color: #1a1a1a;
}

.back-btn {
    position: fixed;
    top: 20px;
    left: 20px;
    padding: 10px 20px;
    background-color: #f0f0f0;
    color: #333;
    text-decoration: none;
    border-radius: 8px;
    font-weight: 600;
    font-size: 0.9rem;
    transition: background-color 0.3s, color 0.3s, transform 0.2s;
    z-index: 1000;
}
.back-btn:hover {
    transform: translateY(-2px);
}

.dark-mode .back-btn {
    background-color: #2a2a2a;
    color: #f0f0f0;
}