body{font-family:Arial, sans-serif;background:#0d1117;color:#e6edf3;margin:0;text-align:center}
header{padding:20px}.logo{width:84px;margin-bottom:10px}
code{display:block;margin-top:6px;opacity:.7}
.chat-box{background:#161b22;border:1px solid #30363d;border-radius:8px;width:92%;max-width:680px;margin:20px auto;padding:12px}
#chat-log{text-align:left;height:280px;overflow-y:auto;margin-bottom:10px;background:#0d1117;padding:6px;border:1px solid #30363d;white-space:pre-wrap}
.user{color:#58a6ff}.ai{color:#3fb950}.error{color:#f85149}
input{width:72%;padding:10px;border:none;border-radius:6px}
button{padding:10px 16px;margin-left:6px;background:#238636;border:none;border-radius:6px;color:#fff;cursor:pointer;font-weight:700}