body {
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
    background-color: var(--background-color);
    color: var(--text-color);
}

header {
    background-color: var(--header-background);
    padding: 1rem;
}

nav ul {
    list-style: none;
    display: flex;
    justify-content: space-around;
}

nav a {
    text-decoration: none;
    color: var(--link-color);
}

.login {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    height: 80vh;
    animation: fadeIn 1s ease-in-out;
}

.login h1 {
    margin-bottom: 1rem;
}

.input-group {
    margin-bottom: 1rem;
    width: 100%;
    max-width: 300px;
}

.input-group label {
    display: block;
    margin-bottom: 0.5rem;
}

.input-group input {
    width: 100%;
    padding: 0.5rem;
    border: 1px solid #ccc;
    border-radius: 4px;
    transition: border-color 0.3s;
}

.input-group input:focus {
    border-color: #0066cc;
}

button {
    padding: 0.5rem 1rem;
    border: none;
    border-radius: 4px;
    background-color: #0066cc;
    color: white;
    cursor: pointer;
    transition: background-color 0.3s;
}

button:hover {
    background-color: #004999;
}

.error-message {
    color: red;
    margin-top: 1rem;
    display: none;
}

footer {
    text-align: center;
    padding: 1rem;
    background-color: var(--footer-background);
    color: var(--footer-text);
}

@keyframes fadeIn {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

:root {
    --background-color: #ffffff;
    --text-color: #000000;
    --header-background: #333333;
    --link-color: #ffffff;
    --footer-background: #333333;
    --footer-text: #ffffff;
}

@media (prefers-color-scheme: dark) {
    :root {
        --background-color: #000000;
        --text-color: #ffffff;
        --header-background: #000000;
        --link-color: #00ccff;
        --footer-background: #000000;
        --footer-text: #00ccff;
    }
}