body {
    margin: 0;
    font-family: Arial, Helvetica, sans-serif;
    line-height: 1.6;
    background: #00979D;
}

header {
    background: #E47128;
    color: white;
    padding: 20px;
    text-align: center;
}

nav {
    background: #994d1d;
    padding: 10px;
    text-align: center;
}

nav a {
    color: white;
    text-decoration: none;
    margin: 0 15px;
    font-weight: bold;
}

nav a:hover {
    text-decoration: underline;
}

section {
    max-width: 900px;
    margin: 30px auto;
    background: white;
    padding: 25px;
    border-radius: 8px;
    box-shadow: 0 0 10px rgba(0,0,0,0.1);
}

button {
    padding: 10px 16px;
    background: #E47128;
    color: white;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    margin: 10px 0;
}

button:hover {
    background: #994d1d;
}

#led {
    width: 60px;
    height: 60px;
    background: red;
    border-radius: 50%;
    margin: 20px auto;
    display: none;
}

pre {
    background: #222;
    color: #0f0;
    padding: 15px;
    border-radius: 6px;
    display: none;
    overflow-x: auto;
}

footer {
    background: #994d1d;
    color: white;
    padding: 20px;
    text-align: center;
    margin-top: 40px;
}