body {
    margin: 0;
    font-family: Arial, sans-serif;
    background: #121212;
    color: #e0e0e0;
    display: flex;
    flex-direction: column;
    height: 100vh; /* full viewport height */
}

header, footer {
    background: #1e1e1e;
    padding: 15px;
    text-align: center;
    border-bottom: 1px solid #333;
}

/* footer border override */
footer {
    border-top: 1px solid #333;
    border-bottom: none;
}

/* middle area (menu + main) fills remaining space */
#container {
    display: flex;
    flex: 1;          /* take all remaining height between header and footer */
    overflow: hidden; /* prevent it from pushing footer */
}

nav, #main {
    height: 100%;
}

nav {
    width: 220px;
    background: #1a1a1a;
    padding: 15px;
    border-right: 1px solid #333;
    overflow-y: auto; /* scroll if menu is tall */
}

nav ul {
    list-style: none;
    padding: 0;
}

nav ul li {
    margin-bottom: 10px;
    font-weight: bold;
}

nav ul li ul {
    margin-top: 5px;
    margin-left: 15px;
}

nav a {
    color: #80bfff;
    text-decoration: none;
}

nav a:hover {
    color: #cce6ff;
}

#main {
    flex: 1;
    padding: 20px;
    overflow-y: auto; /* main scrolls independently */
}

.content h2 {
    margin-top: 0;
}

#btnCopy {
    background: #333;
    color: #e0e0e0;
    border: 1px solid #555;
    padding: 4px 10px;
    cursor: pointer;
}

#btnCopy:hover {
    background: #444;
}


header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    background: #1e1e1e;
    padding: 15px;
    border-bottom: 1px solid #333;
}

.header-buttons {
    display: flex;
    gap: 10px;
}

.header-buttons button {
    background: #333;
    color: #e0e0e0;
    border: 1px solid #555;
    padding: 6px 10px;
    cursor: pointer;
    border-radius: 4px;
    font-size: 18px;
}

.header-buttons button:hover {
    background: #444;
}