*{margin:0;padding:0;box-sizing:border-box}
:root{--primary:#075e54;--primary-light:#128c7e;--bg:#f0f2f5;--surface:#fff;--text:#303030;--muted:#667781;--border:#e9edef;--msg-out:#d9fdd3;--msg-in:#fff;--blue:#34b7f1}
body.dark{--bg:#0b141a;--surface:#111b21;--text:#e9eef6;--muted:#8696a0;--border:#222d33;--msg-out:#005c4b;--msg-in:#202c33}
body{font-family:'Segoe UI',system-ui,sans-serif;background:var(--bg);color:var(--text);height:100vh;overflow:hidden}
.screen{display:none;position:fixed;inset:0}
.screen.active{display:block}
.hidden{display:none!important}

#screen-pairing{display:none;align-items:center;justify-content:center;background:linear-gradient(135deg,#075e54,#128c7e);min-height:100vh}
#screen-pairing.active{display:flex}
.pairing-card{background:var(--surface);padding:32px 28px;border-radius:16px;text-align:center;max-width:360px;width:92%;box-shadow:0 8px 32px rgba(0,0,0,.15)}
.pairing-logo{margin-bottom:10px}
.pairing-card h1{color:var(--primary);font-size:24px;margin-bottom:4px}
.pairing-sub{color:var(--muted);font-size:13px;margin-bottom:16px}
.qr-box{background:#f8f8f8;border-radius:12px;padding:14px;margin-bottom:14px;border:2px dashed var(--border)}
.qr-img{width:180px;height:180px;display:block;margin:0 auto 6px}
.qr-hint{font-size:11px;color:var(--muted)}
.code-box{display:flex;align-items:center;gap:8px;padding:10px 14px;background:var(--bg);border-radius:8px;margin-bottom:14px;justify-content:center}
.code-label{font-size:11px;color:var(--muted)}
.code-value{font-size:14px;font-weight:700;letter-spacing:1px;font-family:monospace;color:var(--primary)}
.btn-copy{padding:4px 10px;font-size:11px;background:var(--primary);color:#fff;border:none;border-radius:4px;cursor:pointer}
.pairing-methods{text-align:left;margin-bottom:16px}
.method-item{display:flex;align-items:flex-start;gap:10px;margin-bottom:10px}
.method-icon{font-size:18px;flex-shrink:0}
.method-item strong{font-size:13px;display:block;margin-bottom:2px}
.method-item p{font-size:11px;color:var(--muted);line-height:1.4}
.btn-full{width:100%}
.pairing-note{font-size:11px;color:var(--muted);margin-top:10px}
.btn-primary{padding:11px 20px;background:var(--primary);color:#fff;border:none;border-radius:8px;font-size:14px;font-weight:600;cursor:pointer}
.btn-primary:hover{background:var(--primary-light)}
.btn-text{padding:10px 16px;background:none;border:none;color:var(--muted);font-size:14px;cursor:pointer}
.btn-text:hover{color:var(--text)}

.chat-layout{display:grid;grid-template-columns:320px 1fr 280px;height:100vh}
.chat-layout.no-info{grid-template-columns:320px 1fr}

.sidebar{background:var(--surface);border-right:1px solid var(--border);display:flex;flex-direction:column}
.sidebar-top{display:flex;align-items:center;justify-content:space-between;padding:10px 14px;border-bottom:1px solid var(--border)}
.sidebar-user{display:flex;align-items:center;gap:10px;flex:1;min-width:0}
.sidebar-user span{font-size:14px;font-weight:500;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.sidebar-icons{display:flex;gap:2px}
.sidebar-icons button{width:34px;height:34px;border-radius:50%;border:none;background:none;font-size:15px;cursor:pointer;display:flex;align-items:center;justify-content:center;color:var(--muted)}
.sidebar-icons button:hover{background:var(--border)}
.search-bar{padding:8px 12px}
.search-input-wrap{display:flex;align-items:center;gap:8px;background:var(--bg);border-radius:8px;padding:8px 12px}
.search-icon{font-size:12px;color:var(--muted)}
.search-input-wrap input{flex:1;border:none;background:none;font-size:13px;outline:none;color:var(--text)}
.chat-tabs{display:flex;padding:0 12px 8px;gap:4px}
.chat-tabs .tab{flex:1;padding:7px;border:none;background:none;font-size:12px;color:var(--muted);cursor:pointer;border-radius:6px}
.chat-tabs .tab.active{background:var(--primary);color:#fff;font-weight:600}
.chat-list{flex:1;overflow-y:auto}
.chat-item{display:flex;align-items:center;padding:10px 12px;gap:10px;cursor:pointer;border-left:3px solid transparent}
.chat-item:hover{background:var(--bg)}
.chat-item.active{background:var(--bg);border-left-color:var(--primary)}
.chat-item-avatar{width:44px;height:44px;border-radius:50%;object-fit:cover;flex-shrink:0}
.chat-item-body{flex:1;min-width:0}
.chat-item-top{display:flex;justify-content:space-between;align-items:center;margin-bottom:2px}
.chat-item-name{font-size:14px;font-weight:500;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.chat-item-time{font-size:11px;color:var(--muted);flex-shrink:0;margin-left:6px}
.chat-item-bottom{display:flex;justify-content:space-between;align-items:center}
.chat-item-msg{font-size:12px;color:var(--muted);overflow:hidden;text-overflow:ellipsis;white-space:nowrap;flex:1}
.unread-badge{background:var(--primary);color:#fff;font-size:10px;font-weight:700;border-radius:10px;padding:1px 6px;min-width:18px;text-align:center;flex-shrink:0}
.empty-list{text-align:center;padding:40px 20px;color:var(--muted);font-size:13px}

.chat-main{background:var(--bg);display:flex;flex-direction:column;position:relative}
.chat-empty{flex:1;display:flex;flex-direction:column;align-items:center;justify-content:center;background:var(--surface);border-bottom:6px solid var(--primary);padding:20px}
.empty-icon{font-size:64px;opacity:.3;margin-bottom:16px}
.chat-empty h2{font-size:20px;font-weight:400;color:var(--text);margin-bottom:8px}
.chat-empty p{font-size:13px;color:var(--muted);text-align:center;line-height:1.5}
.empty-divider{width:80%;height:1px;background:var(--border);margin:24px 0}

.chat-view{flex:1;display:flex;flex-direction:column;min-height:0}
.chat-header{display:flex;align-items:center;padding:8px 14px;background:var(--surface);border-bottom:1px solid var(--border);gap:10px;min-height:56px}
.back-btn{display:none;width:34px;height:34px;border:none;background:none;font-size:20px;cursor:pointer;color:var(--text);border-radius:50%;align-items:center;justify-content:center}
.back-btn:hover{background:var(--border)}
.chat-header .avatar-md{width:40px;height:40px;border-radius:50%;object-fit:cover;cursor:pointer;flex-shrink:0}
.chat-header-text{flex:1;min-width:0}
.chat-header-text h3{font-size:15px;font-weight:600;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.chat-header-text span{font-size:11px;color:var(--muted)}
.chat-header-icons{display:flex;gap:2px}
.chat-header-icons button{width:34px;height:34px;border:none;background:none;font-size:15px;cursor:pointer;border-radius:50%;display:flex;align-items:center;justify-content:center;color:var(--muted)}
.chat-header-icons button:hover{background:var(--border)}

.messages{flex:1;overflow-y:auto;padding:12px 16px;display:flex;flex-direction:column;gap:2px}
.date-divider{text-align:center;margin:8px 0}
.date-divider span{background:var(--surface);color:var(--muted);font-size:11px;padding:4px 10px;border-radius:6px}
.msg-row{display:flex;flex-direction:column;margin-bottom:4px}
.msg-row.out{align-items:flex-end}
.msg-row.in{align-items:flex-start}
.msg-sender{font-size:11px;font-weight:600;color:var(--primary);margin-bottom:2px;padding-left:4px}
.msg-bubble{max-width:70%;padding:6px 10px;border-radius:8px;font-size:14px;line-height:1.4;word-wrap:break-word;position:relative}
.msg-row.out .msg-bubble{background:var(--msg-out);border-bottom-right-radius:2px}
.msg-row.in .msg-bubble{background:var(--msg-in);border-bottom-left-radius:2px;box-shadow:0 1px 2px rgba(0,0,0,.05)}
.msg-content{white-space:pre-wrap}
.msg-img{max-width:280px;border-radius:6px;margin:4px 0;display:block}
.msg-meta{display:flex;align-items:center;gap:4px;font-size:10px;color:var(--muted);justify-content:flex-end;margin-top:2px}
.tick{font-size:12px}
.tick.sent,.tick.delivered{color:var(--muted)}
.tick.read{color:var(--blue)}
.typing-bar{padding:4px 16px;font-size:11px;color:var(--primary);font-style:italic;min-height:20px;background:var(--bg)}

.compose-bar{display:flex;align-items:flex-end;padding:8px 12px;background:var(--surface);border-top:1px solid var(--border);gap:6px;min-height:56px}
.compose-icon{width:38px;height:38px;border-radius:50%;border:none;background:none;font-size:18px;cursor:pointer;display:flex;align-items:center;justify-content:center;flex-shrink:0;color:var(--muted)}
.compose-icon:hover{background:var(--border)}
#msg-input{flex:1;padding:8px 14px;background:var(--bg);border:none;border-radius:18px;font-size:14px;resize:none;outline:none;max-height:80px;line-height:1.4;min-height:38px;color:var(--text)}
.compose-send{width:38px;height:38px;border-radius:50%;border:none;background:var(--primary);color:#fff;font-size:16px;cursor:pointer;display:flex;align-items:center;justify-content:center;flex-shrink:0}
.compose-send:hover{background:var(--primary-light)}

.info-panel{background:var(--surface);border-left:1px solid var(--border);position:relative;overflow-y:auto}
.info-panel.hidden{display:none}
.close-btn{position:sticky;top:10px;right:10px;float:right;width:30px;height:30px;border-radius:50%;border:none;background:var(--border);cursor:pointer;font-size:12px;display:flex;align-items:center;justify-content:center;color:var(--muted);z-index:5}
.close-btn:hover{background:var(--text);color:#fff}
.info-hero{padding:40px 20px 20px;text-align:center}
.info-hero .avatar-xl{width:100px;height:100px;border-radius:50%;object-fit:cover;margin:0 auto 12px;display:block}
.info-hero h2{font-size:18px;margin-bottom:4px}
.info-hero p{font-size:12px;color:var(--muted)}
.info-section{padding:16px 20px;border-top:1px solid var(--border)}
.info-section h3{font-size:12px;color:var(--primary);text-transform:uppercase;letter-spacing:.5px;margin-bottom:12px;font-weight:600}
.member-row{display:flex;align-items:center;gap:10px;padding:6px 0}
.member-row img{width:36px;height:36px;border-radius:50%;object-fit:cover}
.member-row span{font-size:14px;flex:1;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.member-row .role-tag{font-size:10px;color:var(--muted);background:var(--bg);padding:2px 6px;border-radius:4px}
.media-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:4px}
.media-grid img{width:100%;height:80px;object-fit:cover;border-radius:4px;cursor:pointer}
.empty-text{text-align:center;color:var(--muted);font-size:12px;padding:12px 0}

.modal{position:fixed;inset:0;background:rgba(0,0,0,.5);display:none;align-items:center;justify-content:center;z-index:100}
.modal.active{display:flex}
.modal-card{background:var(--surface);border-radius:12px;padding:24px;width:400px;max-width:92%;max-height:85vh;overflow-y:auto}
.modal-sm{width:320px}
.modal-header{text-align:center;margin-bottom:16px}
.modal-header .avatar-lg{width:72px;height:72px;border-radius:50%;margin:0 auto 10px;display:block}
.modal-header h2{font-size:18px;margin-bottom:4px}
.modal-header p{font-size:12px;color:var(--muted)}
.modal-title{font-size:18px;margin-bottom:16px}
.modal-card input[type="text"]{width:100%;padding:10px 14px;border:1px solid var(--border);border-radius:8px;font-size:14px;margin-bottom:12px;outline:none;background:var(--bg);color:var(--text)}
.group-label{font-size:12px;color:var(--muted);margin-bottom:8px;display:block}
.picker-list{max-height:200px;overflow-y:auto;border:1px solid var(--border);border-radius:8px;margin-bottom:16px}
.picker-item{display:flex;align-items:center;gap:10px;padding:8px 12px;cursor:pointer}
.picker-item:hover{background:var(--bg)}
.picker-item img{width:32px;height:32px;border-radius:50%;object-fit:cover}
.picker-item span{flex:1;font-size:14px;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.picker-item input[type="checkbox"]{width:16px;height:16px;accent-color:var(--primary)}
.modal-actions{display:flex;justify-content:flex-end;gap:8px;margin-top:16px}

.settings-list{display:flex;flex-direction:column;gap:12px}
.setting-row{display:flex;align-items:center;justify-content:space-between;gap:12px}
.setting-row span{font-size:13px;color:var(--muted)}
.setting-row input[type="text"]{flex:1;padding:8px 12px;border:1px solid var(--border);border-radius:6px;font-size:13px;outline:none;background:var(--bg);color:var(--text)}
.setting-row input[type="file"]{font-size:12px}
.toggle{position:relative;width:44px;height:24px;display:inline-block}
.toggle input{opacity:0;width:0;height:0}
.toggle-slider{position:absolute;inset:0;background:var(--border);border-radius:12px;cursor:pointer;transition:.3s}
.toggle-slider:before{content:"";position:absolute;width:18px;height:18px;left:3px;top:3px;background:#fff;border-radius:50%;transition:.3s}
.toggle input:checked+.toggle-slider{background:var(--primary)}
.toggle input:checked+.toggle-slider:before{transform:translateX(20px)}

.fab-new-chat{display:none;position:fixed;bottom:20px;right:20px;width:52px;height:52px;border-radius:50%;background:var(--primary);color:#fff;font-size:24px;border:none;cursor:pointer;box-shadow:0 4px 12px rgba(0,0,0,.3);z-index:30;align-items:center;justify-content:center}
.fab-new-chat:hover{background:var(--primary-light)}

@media(max-width:900px){
  .chat-layout{grid-template-columns:1fr!important}
  .info-panel{position:fixed;inset:0;z-index:50}
  .back-btn{display:flex}
  .sidebar{display:none}
  .sidebar.show{display:flex;position:fixed;inset:0;z-index:40}
  .msg-bubble{max-width:88%}
  .fab-new-chat{display:flex}
}
::-webkit-scrollbar{width:5px}
::-webkit-scrollbar-thumb{background:#9993;border-radius:3px}