:root{--primary-color: #f6821f;--primary-hover: #e67e22;--light-bg: #f9fafb;--border-color: #e5e7eb;--text-color: #1f2937;--text-light: #6b7280;--user-msg-bg: #fff2e6;--assistant-msg-bg: #f3f4f6}*{box-sizing:border-box;margin:0;padding:0}body{font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Oxygen,Ubuntu,Cantarell,sans-serif;line-height:1.6;color:var(--text-color);width:100%;margin:0;padding:0}.app{min-height:100vh;display:flex;flex-direction:column}header{text-align:center;margin-bottom:2rem;padding:1rem 0;border-bottom:1px solid var(--border-color)}h1{font-size:1.5rem;color:var(--primary-color)}.chat-container{display:flex;flex-direction:column;height:calc(100vh - 200px);min-height:400px;border:1px solid var(--border-color);border-radius:8px;overflow:hidden;flex:1}.chat-messages{flex:1;overflow-y:auto;padding:1rem;background-color:var(--light-bg);display:flex;flex-direction:column}.message{margin-bottom:1rem;padding:.75rem;border-radius:8px;max-width:80%}.user-message{background-color:var(--user-msg-bg);align-self:flex-end;margin-left:auto}.assistant-message{background-color:var(--assistant-msg-bg);align-self:flex-start}.message-input{display:flex;padding:.75rem;border-top:1px solid var(--border-color);background-color:#fff}#user-input{flex:1;padding:.75rem;border:1px solid var(--border-color);border-radius:4px;font-family:inherit;resize:none;min-height:44px}#send-button{margin-left:.5rem;padding:0 1rem;background-color:var(--primary-color);color:#fff;border:none;border-radius:4px;cursor:pointer;transition:background-color .2s}#send-button:hover{background-color:var(--primary-hover)}#send-button:disabled{background-color:var(--text-light);cursor:not-allowed}.typing-indicator{display:none;margin-bottom:1rem;font-style:italic;color:var(--text-light)}.typing-indicator.visible{display:block}footer{margin-top:1rem;text-align:center;font-size:.85rem;color:var(--text-light)}