*{box-sizing:border-box}
html,body{margin:0;padding:0;height:100%;font-family:Arial,Helvetica,sans-serif;background:#f3f5fb}
.chat-app{display:flex;flex-direction:column;height:100vh;max-width:480px;margin:0 auto;background:#fff}
.chat-header{display:flex;align-items:center;padding:16px;background:#4b67e8;color:#fff}
.chat-avatar{width:42px;height:42px;border-radius:50%;object-fit:cover;background:#fff;margin-right:12px}
.chat-title{font-size:18px;font-weight:700;line-height:1.2}
.chat-welcome{font-size:12px;opacity:.9;margin-top:4px}
.chat-messages{flex:1;overflow-y:auto;padding:16px;background:#f7f8fc}
.chat-empty{text-align:center;color:#999;padding:24px 0}
.msg-row{display:flex;margin-bottom:14px}
.msg-row.user{justify-content:flex-end}
.msg-wrap{max-width:78%;display:flex;flex-direction:column;gap:6px}
.msg-bubble{padding:10px 12px;border-radius:12px;word-break:break-word;font-size:14px;line-height:1.5}
.msg-row.user .msg-bubble{background:#4b67e8;color:#fff;border-bottom-right-radius:4px}
.msg-row.admin .msg-bubble{background:#fff;color:#333;border:1px solid #e5e7ef;border-bottom-left-radius:4px}
.msg-image{max-width:180px;border-radius:10px;display:block}
.msg-time{font-size:11px;color:#94a3b8}
.msg-row.user .msg-time{text-align:right}
.msg-row.admin .msg-time{text-align:left}
.chat-footer{display:flex;align-items:center;padding:12px;border-top:1px solid #eceef5;background:#fff}
.chat-upload{width:38px;height:38px;display:flex;align-items:center;justify-content:center;border-radius:8px;background:#f3f5fb;cursor:pointer;margin-right:8px;font-size:18px}
.chat-upload input{display:none}
.chat-input{flex:1;height:38px;border:1px solid #dfe3f0;border-radius:8px;padding:0 12px;font-size:14px;outline:none}
.chat-send{height:38px;border:0;background:#4b67e8;color:#fff;border-radius:8px;padding:0 16px;margin-left:8px;cursor:pointer}