*{
    margin:0;
    padding:0;
    box-sizing:border-box;
}

body{
    background:#0f172a;
    color:white;
    font-family:Arial, sans-serif;
    height:100vh;
}

.app{
    max-width:1000px;
    margin:auto;
    height:100vh;
    display:flex;
    flex-direction:column;
    padding:20px;
}

.topbar{
    text-align:center;
    padding:20px;
    border-bottom:1px solid rgba(255,255,255,0.1);
}

.topbar h1{
    font-size:32px;
    margin-bottom:10px;
}

.topbar p{
    color:#94a3b8;
}

.chat-box{
    flex:1;
    overflow-y:auto;
    padding:20px 0;
}

.message{
    max-width:80%;
    padding:14px;
    margin-bottom:15px;
    border-radius:14px;
    line-height:1.7;
    white-space:pre-wrap;
}

.user{
    background:#2563eb;
    margin-left:auto;
}

.ai{
    background:#1e293b;
    margin-right:auto;
}

.input-area{
    display:flex;
    gap:10px;
    padding-top:15px;
}

#user-input{
    flex:1;
    padding:14px;
    border:none;
    border-radius:12px;
    outline:none;
    font-size:16px;
}

#send-btn{
    background:#7c3aed;
    color:white;
    border:none;
    border-radius:12px;
    padding:14px 20px;
    cursor:pointer;
    font-size:16px;
    transition:0.3s;
}

#send-btn:hover{
    opacity:0.9;
}