:root{--navy:#153246;--navy2:#0f2939;--blue:#1685bd;--blue2:#0f72a5;--bg:#f2f6f8;--surface:#fff;--line:#dce6eb;--text:#17313f;--muted:#6d818c;--green:#2b9b69;--red:#b74b4b;--shadow:0 8px 30px rgba(17,49,67,.08)}*{box-sizing:border-box}html,body{height:100%;margin:0;font-family:Inter,Segoe UI,Arial,sans-serif;color:var(--text);background:var(--bg)}button,a,textarea{font:inherit}.hidden{display:none!important}.app-shell{min-height:100%;display:grid;grid-template-columns:238px 1fr}.sidebar{background:linear-gradient(180deg,var(--navy),var(--navy2));color:#fff;padding:24px 16px;display:flex;flex-direction:column}.brand{display:flex;align-items:center;gap:11px;padding:0 8px 26px}.brand img{width:43px;height:43px;object-fit:contain}.brand strong{display:block;font-size:21px;letter-spacing:.04em}.brand span{display:block;font-size:11px;opacity:.72;text-transform:uppercase;letter-spacing:.11em;margin-top:1px}.sidebar nav{display:flex;flex-direction:column;gap:5px}.nav-item{border:0;background:transparent;color:#d8e5eb;text-align:left;padding:11px 12px;border-radius:9px;cursor:pointer}.nav-item span{display:inline-block;width:25px}.nav-item.active{background:rgba(255,255,255,.12);color:#fff;font-weight:600}.nav-item.disabled{opacity:.42;cursor:default}.nav-divider{font-size:10px;letter-spacing:.12em;opacity:.42;padding:23px 12px 7px}.sidebar-footer{margin-top:auto;padding:12px 8px 0;font-size:11px;opacity:.4}.main{min-width:0}.topbar{height:92px;background:#fff;border-bottom:1px solid var(--line);display:flex;align-items:center;justify-content:space-between;padding:0 32px}.topbar h1{font-size:24px;margin:0;color:var(--navy)}.topbar p{margin:4px 0 0;color:var(--muted);font-size:13px}.user-menu{text-align:right;font-size:13px}.user-menu span{display:block;font-weight:600}.user-menu a{display:block;color:var(--blue);font-size:12px;margin-top:3px;text-decoration:none}.workspace{padding:24px;display:grid;grid-template-columns:minmax(330px,38%) minmax(430px,1fr);gap:20px;height:calc(100vh - 92px)}.panel{background:var(--surface);border:1px solid var(--line);border-radius:14px;box-shadow:var(--shadow);min-height:0}.conversation-column{display:flex;flex-direction:column;overflow:hidden}.panel-title,.panel-subtitle{display:flex;align-items:center;justify-content:space-between;padding:18px 18px 13px;border-bottom:1px solid var(--line)}.panel-title>div{display:flex;align-items:center;gap:8px}.panel-title h2,.panel-subtitle h3{margin:0;font-size:15px}.panel-subtitle{padding:14px 18px 10px;background:#f9fbfc}.count{background:#e6f3f9;color:var(--blue2);font-size:11px;font-weight:700;border-radius:20px;padding:2px 7px}.icon-button{border:1px solid var(--line);background:#fff;border-radius:8px;width:34px;height:32px;cursor:pointer;color:var(--navy);font-size:18px}.conversation-list{overflow:auto;max-height:44%}.conversation-item{padding:14px 17px;border-bottom:1px solid #edf2f4;cursor:pointer}.conversation-item:hover,.conversation-item.selected{background:#f0f8fc}.conversation-top{display:flex;justify-content:space-between;gap:8px}.conversation-name{font-weight:650;font-size:14px}.conversation-time{font-size:11px;color:var(--muted)}.conversation-preview{font-size:12px;color:var(--muted);white-space:nowrap;overflow:hidden;text-overflow:ellipsis;margin-top:5px}.device-list{overflow:auto;flex:1}.device-item{padding:12px 17px;border-bottom:1px solid #edf2f4;display:grid;grid-template-columns:1fr auto;gap:8px;align-items:center}.device-name{font-size:13px;font-weight:600}.device-meta{font-size:11px;color:var(--muted);margin-top:3px}.toggle{position:relative;width:42px;height:23px;border:0;border-radius:20px;background:#c7d2d8;cursor:pointer}.toggle:after{content:"";position:absolute;width:17px;height:17px;background:#fff;border-radius:50%;top:3px;left:3px;transition:.18s;box-shadow:0 1px 3px #789}.toggle.on{background:var(--green)}.toggle.on:after{left:22px}.empty-list{padding:24px;text-align:center;color:var(--muted);font-size:13px}.muted{font-size:11px;color:var(--muted)}.chat-column{overflow:hidden}.chat-empty{height:100%;display:flex;flex-direction:column;align-items:center;justify-content:center;text-align:center;color:var(--muted)}.chat-empty img{width:82px;height:82px;object-fit:contain;opacity:.85}.chat-empty h2{color:var(--navy);margin:16px 0 5px}.chat-empty p{margin:0}.chat-active{height:100%;display:grid;grid-template-rows:auto 1fr auto}.chat-header{padding:17px 20px;border-bottom:1px solid var(--line);display:flex;justify-content:space-between;align-items:center}.chat-header h2{margin:0;font-size:17px}.status-line{font-size:11px;color:var(--muted);margin-top:4px}.messages{padding:20px;overflow:auto;background:#f8fafb}.message{max-width:72%;margin:0 0 12px}.message.client{margin-right:auto}.message.technician{margin-left:auto}.bubble{padding:10px 13px;border-radius:15px;background:#fff;border:1px solid var(--line);font-size:14px;white-space:pre-wrap}.technician .bubble{background:#e4f3fb;border-color:#c6e2f0}.message-meta{font-size:10px;color:var(--muted);margin:4px 5px}.technician .message-meta{text-align:right}.composer{padding:14px;border-top:1px solid var(--line);display:grid;grid-template-columns:1fr auto;gap:10px}.composer textarea{resize:none;border:1px solid #cfdce2;border-radius:20px;padding:10px 14px;outline:none;max-height:100px}.composer textarea:focus{border-color:var(--blue)}.primary-button,.secondary-button{display:inline-block;border:0;border-radius:20px;padding:10px 18px;text-decoration:none;cursor:pointer}.primary-button{background:var(--blue);color:#fff;font-weight:600}.primary-button:hover{background:var(--blue2)}.secondary-button{background:#fff;border:1px solid var(--line);color:var(--muted);font-size:12px}.login-shell{height:100%;display:flex;align-items:center;justify-content:center;background:radial-gradient(circle at 50% 20%,#eaf5fa,#edf2f4)}.login-card{width:390px;background:#fff;border:1px solid var(--line);border-radius:18px;padding:38px;text-align:center;box-shadow:var(--shadow)}.login-card img{width:88px}.login-card h1{color:var(--navy);margin:17px 0 7px}.login-card p{color:var(--muted);margin:0 0 25px}.toast{position:fixed;right:24px;bottom:24px;background:var(--navy);color:#fff;padding:12px 16px;border-radius:9px;box-shadow:var(--shadow);font-size:13px}@media(max-width:850px){.app-shell{grid-template-columns:74px 1fr}.brand div,.nav-item:not(.active),.nav-divider,.sidebar-footer{display:none}.brand{padding:0 0 25px;justify-content:center}.workspace{grid-template-columns:1fr;height:auto}.conversation-column{min-height:500px}.chat-column{min-height:600px}.topbar{padding:0 20px}}

.archive-title{cursor:default}.archive-list{overflow:auto;max-height:22%;border-bottom:1px solid var(--line)}.archive-list .conversation-item{padding:10px 17px;background:#fbfcfd}.archive-list .conversation-name{font-size:12px}.archive-list .conversation-preview{font-size:11px}.empty-list.compact{padding:13px}.presence{display:inline-block;width:8px;height:8px;border-radius:50%;background:#9aaab2;margin-right:6px;vertical-align:1px}.presence.online{background:#2b9b69;box-shadow:0 0 0 2px rgba(43,155,105,.12)}.device-status{display:flex;align-items:center}.archived-badge{font-size:10px;color:#7a8b94;background:#eef2f4;border-radius:10px;padding:2px 6px;margin-left:6px}.conversation-item.archived{opacity:.82}