body {
    font-family: Arial, sans-serif;
    margin: 0;
    background: #f4f6f9;
    color: #333;
    text-align: center;
}

header {
    background: #0f172a;
    color: white;
    padding: 40px;
}

section {
    padding: 40px;
}

footer {
    background: #111;
    color: white;
    padding: 20px;
}

/* --- Send Button Professional Style --- */
#send-btn {
    background: #2563eb;
    color: white;
    border: none;
    padding: 10px 22px;
    border-radius: 8px;
    font-weight: 600;
    font-size: 14px;
    cursor: not-allowed;
    opacity: 0.6;
    transition: all 0.25s ease;
    width: fit-content;
}

#send-btn.enabled {
    cursor: pointer;
    opacity: 1;
}

#send-btn.enabled:hover {
    background: #1e40af;
}