body.dark { background: #121212; color: #fff; font-family: sans-serif; margin: 0; display: flex; }
.sidebar { width: 220px; background: #1e1e1e; padding: 1em; height: 100vh; }
.main { flex: 1; padding: 1em; background: #2a2a2a; }
textarea, select { width: 100%; margin: 0.5em 0; background: #000; color: #0f0; padding: 0.5em; }
iframe { width: 100%; height: 300px; background: white; }
button { margin-right: 5px; padding: 0.5em; }