* { box-sizing: border-box; margin: 0; padding: 0; }
body { font-family: system-ui, sans-serif; background: #111; color: #eee; }
#app { max-width: 600px; margin: 0 auto; padding: 1rem; }
input, button { padding: 0.5rem; margin: 0.5rem 0; width: 100%; }
button { background: #0a84ff; color: white; border: none; cursor: pointer; }
.chat-list-item { padding: 0.8rem; border-bottom: 1px solid #333; cursor: pointer; }
.message { margin: 0.5rem 0; padding: 0.5rem; background: #222; border-radius: 8px; }