* { box-sizing: border-box; }
body { margin:0; font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC","Hiragino Sans GB","Microsoft YaHei","Helvetica Neue", Arial, "Noto Sans", sans-serif; background:#f6f7fb; color:#222; }

.topbar { display:flex; align-items:center; justify-content:space-between; padding:12px 16px; background:#0ea5e9; color:#fff; }
.topbar .brand { font-weight:700; font-size:18px; }
.topbar .desc { font-size:14px; opacity:.95; }

.app, .admin-app { max-width:960px; margin:0 auto; }

.chat { padding:12px; }
.messages { background:#fff; height:60vh; border-radius:12px; padding:12px; overflow:auto; box-shadow:0 2px 8px rgba(0,0,0,.05); }

.msg { display:flex; margin:8px 0; }
.msg.left { justify-content:flex-start; }
.msg.right { justify-content:flex-end; }
.bubble { max-width:70%; padding:10px 12px; border-radius:12px; line-height:1.4; white-space:pre-wrap; word-break:break-word; }
.left .bubble { background:#f1f5f9; }
.right .bubble { background:#dbeafe; }
.image { max-width:46vw; border-radius:12px; display:block; }

.sysline { text-align:center; font-size:12px; color:#666; margin:8px 0; }

.composer { display:flex; gap:8px; margin-top:10px; }
.composer textarea { flex:1; resize:vertical; min-height:44px; max-height:30vh; padding:10px; border:1px solid #e5e7eb; border-radius:10px; }
.composer button { background:#0ea5e9; border:none; color:#fff; border-radius:10px; padding:0 16px; cursor:pointer; }
.composer button:hover { filter:brightness(.95); }

.toolbar { margin:10px 0; display:flex; gap:8px; align-items:center; }
.upload-btn { display:inline-block; background:#e2e8f0; padding:6px 10px; border-radius:8px; cursor:pointer; }
.danger { background:#ef4444; color:#fff; border:none; border-radius:8px; padding:6px 12px; cursor:pointer; }

.admin-main { display:flex; gap:12px; padding:12px; }
.sidebar { width:320px; }
.conv-panel, .login-panel { background:#fff; padding:12px; border-radius:12px; box-shadow:0 2px 8px rgba(0,0,0,.05); }
.panel-title { font-weight:700; margin-bottom:8px; }
.conv-list { max-height:60vh; overflow:auto; }
.conv-item { border:1px solid #e5e7eb; border-radius:8px; padding:8px; margin-bottom:8px; cursor:pointer; background:#f9fafb; }
.conv-item:hover { background:#eef2ff; }
.conv-title { font-weight:600; margin-bottom:4px; }
.conv-last { font-size:12px; color:#666; }

.hidden { display:none; }