*{margin:0;padding:0;box-sizing:border-box}:root{--bg-light: #ffffff;--text-light: #333333;--msg-user-light: #007bff;--msg-bot-light: #f8f9fa;--input-bg-light: #f5f5f5;--bg-dark: #1a1a1a;--text-dark: #e0e0e0;--msg-user-dark: #0066cc;--msg-bot-dark: #2d2d2d;--input-bg-dark: #333333}body.light-mode{background-color:var(--bg-light);color:var(--text-light)}body.dark-mode{background-color:var(--bg-dark);color:var(--text-dark)}.app-container{display:flex;flex-direction:column;height:100vh;max-width:1200px;margin:0 auto;font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Oxygen,Ubuntu,Cantarell,sans-serif}.header{display:flex;justify-content:space-between;align-items:center;padding:1rem 2rem;border-bottom:1px solid #ddd}body.dark-mode .header{border-bottom:1px solid #444}.theme-toggle{padding:.5rem 1rem;border:none;border-radius:8px;cursor:pointer;font-size:1rem;transition:all .3s}body.light-mode .theme-toggle{background:#007bff;color:#fff}body.dark-mode .theme-toggle{background:#06c;color:#fff}.messages-container{flex:1;overflow-y:auto;padding:2rem;display:flex;flex-direction:column;gap:1rem}.message{padding:1rem;border-radius:12px;max-width:80%;word-wrap:break-word}.message.user{align-self:flex-end;margin-left:auto}body.light-mode .message.user{background:var(--msg-user-light);color:#fff}body.dark-mode .message.user{background:var(--msg-user-dark);color:#fff}.message.assistant{align-self:flex-start}body.light-mode .message.assistant{background:var(--msg-bot-light);color:var(--text-light)}body.dark-mode .message.assistant{background:var(--msg-bot-dark);color:var(--text-dark)}.message code{background:#0000001a;padding:.2rem .4rem;border-radius:4px;font-family:Courier New,monospace}.message pre{margin:.5rem 0;border-radius:8px;overflow-x:auto}.loading{text-align:center;padding:1rem;font-style:italic;opacity:.7}.input-container{display:flex;gap:1rem;padding:1rem 2rem;border-top:1px solid #ddd}body.dark-mode .input-container{border-top:1px solid #444}.input-container input{flex:1;padding:.75rem 1rem;border:1px solid #ddd;border-radius:8px;font-size:1rem}body.light-mode .input-container input{background:var(--input-bg-light);color:var(--text-light)}body.dark-mode .input-container input{background:var(--input-bg-dark);color:var(--text-dark);border-color:#555}.input-container button{padding:.75rem 2rem;background:#007bff;color:#fff;border:none;border-radius:8px;cursor:pointer;font-size:1rem;transition:all .3s}.input-container button:hover:not(:disabled){background:#0056b3}.input-container button:disabled{opacity:.5;cursor:not-allowed}@media (max-width: 768px){.header,.input-container,.messages-container{padding:1rem}.message{max-width:90%}.input-container{flex-direction:column}.input-container button{width:100%}}