body{font-family:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Helvetica,Arial,sans-serif;margin:0;background-color:#f4f4f9;display:flex;justify-content:center;align-items:center;height:100vh}
.chat-container{width:90%;max-width:700px;height:90vh;background:#fff;border-radius:10px;box-shadow:0 4px 20px rgba(0,0,0,.1);display:flex;flex-direction:column}
.chat-header{background:#5a67d8;color:#fff;padding:15px;text-align:center;border-top-left-radius:10px;border-top-right-radius:10px}
.chat-header h2{margin:0;font-size:1.2em}
.chat-box{flex-grow:1;overflow-y:auto;padding:20px;display:flex;flex-direction:column;gap:15px}
.message{padding:10px 15px;border-radius:18px;max-width:80%;line-height:1.5;word-wrap:break-word}
.user-message{background-color:#5a67d8;color:#fff;align-self:flex-end;border-bottom-right-radius:4px}
.bot-message{background-color:#e2e8f0;color:#2d3748;align-self:flex-start;border-bottom-left-radius:4px}
.chat-input{display:flex;padding:15px;border-top:1px solid #e2e8f0}
#user-input{flex-grow:1;border:1px solid #cbd5e0;border-radius:20px;padding:10px 15px;font-size:1em}
#user-input:focus{outline:none;border-color:#5a67d8}
#send-btn{margin-left:10px;background:#5a67d8;color:#fff;border:none;padding:10px 20px;border-radius:20px;cursor:pointer;font-size:1em;transition:background-color .3s}
#send-btn:hover{background:#434190}
#send-btn:disabled{background-color:#a0aec0;cursor:not-allowed}