.cs-container{background:#f5f7fa;border-radius:12px;height:calc(100vh - 100px);margin:15px;display:flex;overflow:hidden;box-shadow:0 4px 16px #0000000d}.cs-sidebar{background:#fff;border-right:1px solid #eef2f6;flex-direction:column;width:280px;display:flex}.cs-sidebar-header{color:#333;border-bottom:1px solid #f1f4f8;padding:18px;font-size:15px;font-weight:700}.cs-user-list{flex:1;overflow-y:auto}.cs-user-item{cursor:pointer;align-items:center;padding:14px 18px;transition:background .2s;display:flex;position:relative}.cs-user-item:hover,.cs-user-item.active{background:#f0f7ff}.cs-user-item.active:after{content:"";background:#007bff;width:4px;position:absolute;top:0;bottom:0;left:0}.cs-avatar{color:#fff;background:#007bff;border-radius:50%;justify-content:center;align-items:center;width:40px;height:40px;margin-right:12px;font-size:13px;font-weight:700;display:flex}.cs-user-info{flex:1;overflow:hidden}.cs-username{color:#2c3e50;margin-bottom:4px;font-size:14px;font-weight:600}.cs-last-msg{color:#95a5a6;white-space:nowrap;text-overflow:ellipsis;font-size:12px;overflow:hidden}.cs-badge{color:#fff;background:#ff4d4f;border-radius:10px;padding:2px 6px;font-size:11px}.cs-chat-window{background:#fff;flex-direction:column;flex:1;display:flex}.cs-chat-header{color:#34495e;border-bottom:1px solid #eef2f6;padding:18px;font-weight:600}.cs-messages{background:#f9fbff;flex:1;padding:20px;overflow-y:auto}.cs-message-row{margin-bottom:15px;display:flex}.cs-message-row.left{justify-content:flex-start}.cs-message-row.right{justify-content:flex-end}.cs-msg-bubble{border-radius:12px;max-width:65%;padding:10px 14px;position:relative}.cs-message-row.left .cs-msg-bubble{color:#333;background:#fff;border-bottom-left-radius:2px;box-shadow:0 2px 6px #00000005}.cs-message-row.right .cs-msg-bubble{color:#fff;background:#007bff;border-bottom-right-radius:2px}.cs-msg-text{word-break:break-all;font-size:14px;line-height:1.4}.cs-msg-time{text-align:right;opacity:.6;margin-top:4px;font-size:10px}.cs-input-area{border-top:1px solid #eef2f6;align-items:center;gap:10px;padding:15px;display:flex}.cs-attach-btn{color:#595959;cursor:pointer;background:#f5f5f5;border:1px solid #dcdfe6;border-radius:6px;flex-shrink:0;height:40px;padding:0 12px;font-size:18px}.cs-attach-btn:hover{background:#eef2f6}.cs-msg-image{border-radius:8px;max-width:220px;max-height:220px;display:block}.cs-msg-file{word-break:break-all;font-size:14px;line-height:1.4}.cs-input-area input[type=text]{border:1px solid #dcdfe6;border-radius:6px;outline:none;flex:1;padding:10px 15px;font-size:14px;transition:border-color .2s}.cs-input-area input[type=text]:focus{border-color:#007bff}.cs-input-area button:not(.cs-attach-btn){color:#fff;cursor:pointer;background:#007bff;border:none;border-radius:6px;margin-left:10px;padding:0 20px;font-weight:500}.cs-input-area button:not(.cs-attach-btn):hover{background:#0069d9}.cs-empty-state{color:#95a5a6;flex:1;justify-content:center;align-items:center;font-size:14px;display:flex}