:root{color:#17201c;background:#f4f6f8;font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,Segoe UI,sans-serif}*{box-sizing:border-box}body{margin:0}button,input{font:inherit}.app-shell{display:grid;grid-template-columns:280px minmax(0,1fr);min-height:100vh}.sidebar{background:#101820;color:#f8fbfa;display:flex;flex-direction:column;min-width:0;padding:18px}.brand{align-items:center;display:flex;justify-content:space-between;gap:12px;margin-bottom:24px}.brand div{display:grid;gap:4px}.brand strong{font-size:24px}.brand span{color:#b7c4c0;font-size:13px}.status{border-radius:999px;color:#101820;font-size:12px;padding:5px 9px}.status.connecting{background:#ffd166}.status.online{background:#7bd88f}.status.offline{background:#ff8f8f}.conversation-list{display:grid;gap:8px}.conversation{align-items:center;background:transparent;border:0;border-radius:8px;color:#d8e2df;cursor:pointer;display:flex;gap:10px;min-height:44px;padding:10px;text-align:left}.conversation span{display:grid;gap:2px;min-width:0}.conversation strong{font-size:14px;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.conversation small{color:#aebcb8;font-size:12px;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.conversation em{background:#ffcf5a;border-radius:999px;color:#101820;font-size:12px;font-style:normal;line-height:20px;margin-left:auto;min-width:20px;padding:0 6px;text-align:center}.conversation.active,.conversation:hover{background:#22313d;color:#fff}.chat-panel{display:grid;grid-template-rows:auto minmax(0,1fr) auto;min-width:0}.chat-header{align-items:center;background:#fff;border-bottom:1px solid #dde4e2;display:flex;justify-content:space-between;min-height:72px;padding:14px 20px}.chat-header h1{font-size:22px;margin:0 0 4px}.chat-header span{color:#60716b;font-size:13px}.icon-button{align-items:center;background:#e8f3ef;border:1px solid #cbded7;border-radius:8px;cursor:pointer;display:inline-flex;height:40px;justify-content:center;width:40px}.message-list{display:flex;flex-direction:column;gap:12px;min-height:0;overflow:auto;padding:20px}.empty-state{color:#60716b;margin:auto}.message{align-self:flex-start;background:#fff;border:1px solid #dde4e2;border-radius:8px;max-width:min(620px,86%);padding:10px 12px}.message.mine{align-self:flex-end;background:#dff5ea;border-color:#bfe5d1}.message strong{color:#42534d;display:block;font-size:12px;margin-bottom:4px}.message p{margin:0;overflow-wrap:anywhere}.composer{align-items:center;background:#fff;border-top:1px solid #dde4e2;display:grid;gap:10px;grid-template-columns:minmax(0,1fr) auto;padding:14px}.composer input{border:1px solid #cbd6d2;border-radius:8px;min-height:44px;min-width:0;padding:0 12px}.send-button{align-items:center;background:#177a55;border:0;border-radius:8px;color:#fff;cursor:pointer;display:inline-flex;gap:8px;min-height:44px;padding:0 14px}@media (max-width: 720px){.app-shell{grid-template-columns:1fr}.sidebar{padding:12px}.conversation-list{display:flex;overflow-x:auto}.conversation{flex:0 0 auto}.chat-panel{min-height:calc(100vh - 132px)}}