*{margin:0;padding:0;box-sizing:border-box}body{font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Oxygen,Ubuntu,Cantarell,Fira Sans,Droid Sans,Helvetica Neue,sans-serif;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;background:#f5f5f5}.app{max-width:1200px;margin:0 auto;height:100vh;display:flex;flex-direction:column;background:#fff;box-shadow:0 0 20px #0000001a}.header{background:linear-gradient(135deg,#667eea,#764ba2);color:#fff;padding:20px;display:flex;justify-content:space-between;align-items:center}.header h1{font-size:24px;font-weight:600}.badge{background:#fff3;padding:6px 12px;border-radius:20px;font-size:12px;font-weight:500}.chat-container{flex:1;overflow-y:auto;padding:20px;background:#fafafa}.empty-state{text-align:center;padding:60px 20px;color:#666}.empty-state h2{font-size:28px;margin-bottom:10px;color:#333}.messages{display:flex;flex-direction:column;gap:16px}.message{max-width:70%;padding:12px 16px;border-radius:12px;animation:slideIn .3s ease}@keyframes slideIn{0%{opacity:0;transform:translateY(10px)}to{opacity:1;transform:translateY(0)}}.message.user{align-self:flex-end;background:#667eea;color:#fff;border-bottom-right-radius:4px}.message.assistant{align-self:flex-start;background:#fff;color:#333;border:1px solid #e0e0e0;border-bottom-left-radius:4px}.message-content{line-height:1.5;word-wrap:break-word}.message-content.loading{color:#999;font-style:italic}.message-time{font-size:11px;margin-top:6px;opacity:.6}.input-container{padding:20px;background:#fff;border-top:1px solid #e0e0e0;display:flex;gap:10px}.input{flex:1;padding:12px 16px;border:2px solid #e0e0e0;border-radius:24px;font-size:15px;outline:none;transition:border-color .2s}.input:focus{border-color:#667eea}.input:disabled{background:#f5f5f5;cursor:not-allowed}.send-btn,.clear-btn{padding:12px 24px;border:none;border-radius:24px;font-size:15px;font-weight:500;cursor:pointer;transition:all .2s}.send-btn{background:#667eea;color:#fff}.send-btn:hover:not(:disabled){background:#5568d3;transform:translateY(-1px)}.send-btn:disabled{background:#ccc;cursor:not-allowed}.clear-btn{background:#f5f5f5;color:#666}.clear-btn:hover:not(:disabled){background:#e0e0e0}.clear-btn:disabled{opacity:.5;cursor:not-allowed}