*{box-sizing:border-box}body{margin:0;font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,sans-serif;background:#f5f5f5;color:#111}#app{display:flex;flex-direction:column;height:100vh;max-width:720px;margin:0 auto;background:#fff}#header{display:flex;align-items:center;gap:8px;padding:12px 16px;border-bottom:1px solid #eee;background:#fff}#header h1{margin:0;font-size:18px;font-weight:600}#back-btn{border:none;background:none;font-size:20px;padding:4px 8px}#main{flex:1;overflow:hidden;display:flex;flex-direction:column}#loading,#error{padding:24px 16px;text-align:center;color:#666}#error{color:#c62828}.hidden{display:none!important}#conversation-list{list-style:none;margin:0;padding:0;overflow-y:auto;flex:1}#conversation-list li{display:flex;align-items:center;gap:12px;padding:12px 16px;border-bottom:1px solid #f0f0f0;cursor:pointer}#conversation-list li:active{background:#f7f7f7}.avatar{width:44px;height:44px;border-radius:8px;background:#e0e0e0;object-fit:cover}.conv-meta{flex:1;min-width:0}.conv-name{font-size:16px;font-weight:500}.conv-preview{font-size:13px;color:#888;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}#chat-view{display:flex;flex-direction:column;flex:1;min-height:0}#messages{flex:1;overflow-y:auto;padding:12px 16px;background:#f7f7f7}.msg-row{display:flex;margin-bottom:10px}.msg-row.self{justify-content:flex-end}.bubble{max-width:75%;padding:8px 12px;border-radius:12px;background:#fff;font-size:15px;line-height:1.4;word-break:break-word}.msg-row.self .bubble{background:#95ec69}#send-form{display:flex;gap:8px;padding:10px 12px;border-top:1px solid #eee;background:#fff}#message-input{flex:1;border:1px solid #ddd;border-radius:20px;padding:8px 14px;font-size:15px}#send-form button{border:none;background:#07c160;color:#fff;border-radius:20px;padding:8px 16px;font-size:15px}.header-action{margin-left:auto;border:1px solid #07c160;background:#fff;color:#07c160;border-radius:16px;padding:4px 12px;font-size:13px}.call-bar{display:flex;gap:8px;padding:8px 12px;border-bottom:1px solid #eee;background:#fafafa}.call-bar button{flex:1;border:1px solid #ddd;background:#fff;border-radius:8px;padding:8px}.group-tag{display:inline-block;font-size:10px;background:#e3f2fd;color:#1565c0;padding:1px 4px;border-radius:3px;margin-right:4px}.msg-image{max-width:200px;border-radius:8px}.msg-video{max-width:240px;border-radius:8px}#attach-btn,#record-btn{border:1px solid #ddd;background:#fff;border-radius:50%;width:36px;height:36px;padding:0;color:#333}#record-btn.recording{background:#ffcdd2;border-color:#e53935}.modal{position:fixed;top:0;right:0;bottom:0;left:0;background:#00000073;display:flex;align-items:center;justify-content:center;z-index:100}.modal-content{background:#fff;border-radius:12px;padding:20px;width:min(90vw,360px)}.modal-content h2{margin:0 0 12px;font-size:18px}.modal-content input,.modal-content textarea{width:100%;margin-bottom:10px;padding:8px 10px;border:1px solid #ddd;border-radius:8px;font-size:14px}.modal-content textarea{min-height:80px;resize:vertical}.modal-actions{display:flex;gap:8px;justify-content:flex-end}.modal-actions button{border:none;border-radius:8px;padding:8px 16px}#group-ok-btn{background:#07c160;color:#fff}#call-overlay{position:fixed;top:0;right:0;bottom:0;left:0;background:#1a1a2e;color:#fff;z-index:200;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:16px;padding:24px}#call-title{font-size:20px;font-weight:600}#call-status{font-size:14px;color:#ccc}#call-duration{font-size:28px;font-variant-numeric:tabular-nums}.call-videos{display:flex;gap:12px;width:100%;max-width:480px;justify-content:center}#call-local-video,#call-remote-video{width:140px;height:180px;background:#333;border-radius:8px;object-fit:cover}.call-actions{display:flex;gap:24px;margin-top:24px}.call-actions button{width:64px;height:64px;border-radius:50%;border:none;font-size:14px;color:#fff}#call-accept-btn{background:#07c160}#call-reject-btn,#call-hangup-btn{background:#e53935}