:root{--bg:#f5f5f5;--bg-panel:#fff;--bg-hover:#f0f0f0;--bg-active:#e3e8f0;--text:#1a1a2e;--text-secondary:#6b7280;--accent:#4f46e5;--accent-hover:#4338ca;--accent-light:#eef2ff;--border:#e5e7eb;--danger:#ef4444;--success:#22c55e;--bubble-own:#4f46e5;--bubble-own-text:#fff;--bubble-other:#fff;--bubble-other-text:#1a1a2e;--shadow:0 1px 3px #00000014;--radius:8px;color:var(--text);background:var(--bg);font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,sans-serif;font-size:15px;line-height:1.5}@media (prefers-color-scheme:dark){:root{--bg:#0f172a;--bg-panel:#1e293b;--bg-hover:#334155;--bg-active:#3b4f6f;--text:#e2e8f0;--text-secondary:#94a3b8;--accent:#818cf8;--accent-hover:#6366f1;--accent-light:#1e1b4b;--border:#334155;--bubble-own:#6366f1;--bubble-own-text:#fff;--bubble-other:#1e293b;--bubble-other-text:#e2e8f0;--shadow:0 1px 3px #0000004d}}*{box-sizing:border-box;margin:0;padding:0}body{margin:0;overflow:hidden}#root{flex-direction:column;height:100dvh;display:flex}.auth-page{background:var(--bg);justify-content:center;align-items:center;height:100dvh;display:flex}.auth-form{background:var(--bg-panel);box-shadow:var(--shadow);border-radius:12px;flex-direction:column;gap:16px;width:100%;max-width:400px;padding:40px;display:flex}.auth-form h1{text-align:center;margin-bottom:8px;font-size:24px;font-weight:600}.auth-form input{border:1px solid var(--border);border-radius:var(--radius);background:var(--bg);color:var(--text);outline:none;padding:12px 16px;font-size:15px;transition:border-color .2s}.auth-form input:focus{border-color:var(--accent)}.auth-form button[type=submit]{background:var(--accent);color:#fff;border-radius:var(--radius);cursor:pointer;border:none;padding:12px;font-size:15px;font-weight:500;transition:background .2s}.auth-form button[type=submit]:hover{background:var(--accent-hover)}.auth-form button:disabled{opacity:.6;cursor:not-allowed}.auth-link{text-align:center;color:var(--text-secondary);font-size:14px}.auth-link a{color:var(--accent);text-decoration:none}.error{color:var(--danger);border-radius:var(--radius);background:#fef2f2;padding:10px 14px;font-size:14px}@media (prefers-color-scheme:dark){.error{background:#450a0a}}.success{color:var(--success);border-radius:var(--radius);background:#f0fdf4;padding:10px 14px;font-size:14px}@media (prefers-color-scheme:dark){.success{background:#052e16}}.loading-screen{height:100dvh;color:var(--text-secondary);justify-content:center;align-items:center;font-size:18px;display:flex}.chat-page{height:100dvh;display:flex;overflow:hidden}.sidebar{background:var(--bg-panel);border-right:1px solid var(--border);flex-direction:column;width:320px;min-width:320px;display:flex;overflow:hidden}.sidebar-backdrop{display:none}.sidebar-toggle{z-index:25;background:var(--bg-panel);border:1px solid var(--border);border-radius:var(--radius);cursor:pointer;color:var(--text);padding:6px 10px;display:none;position:absolute;top:12px;left:12px}@media (width<=768px){.sidebar{z-index:20;width:85vw;min-width:0;max-width:320px;transition:left .2s;position:absolute;top:0;bottom:0;left:-320px}.sidebar.open{left:0}.sidebar-backdrop{z-index:15;background:#0006;display:block;position:fixed;inset:0}.sidebar-toggle{display:block}.message-input{padding:8px 10px}.message-text-input{font-size:16px}}.sidebar-user{border-bottom:1px solid var(--border);justify-content:space-between;align-items:center;padding:12px 16px;display:flex}.user-display-name{font-size:16px;font-weight:600}.sidebar-actions{gap:4px;display:flex}.chat-list{flex-direction:column;flex:1;display:flex;overflow:hidden}.chat-list-header{justify-content:space-between;align-items:center;padding:12px 16px;display:flex}.chat-list-header h2{font-size:16px;font-weight:600}.chat-list-items{flex:1;overflow-y:auto}.chat-list-item{cursor:pointer;align-items:center;gap:12px;padding:12px 16px;transition:background .15s;display:flex}.chat-list-item:hover{background:var(--bg-hover)}.chat-list-item.active{background:var(--bg-active)}.chat-avatar{background:var(--accent-light);width:44px;min-width:44px;height:44px;color:var(--accent);border-radius:50%;justify-content:center;align-items:center;font-size:18px;font-weight:600;display:flex}.chat-info{flex:1;min-width:0}.chat-name{white-space:nowrap;text-overflow:ellipsis;font-weight:500;overflow:hidden}.chat-last-message{color:var(--text-secondary);white-space:nowrap;text-overflow:ellipsis;font-size:13px;overflow:hidden}.chat-time{color:var(--text-secondary);white-space:nowrap;font-size:12px}.chat-list-empty{text-align:center;color:var(--text-secondary);padding:40px 16px;font-size:14px}.chat-area{background:var(--bg);flex-direction:column;flex:1;display:flex;overflow:hidden}.chat-area.empty{color:var(--text-secondary);justify-content:center;align-items:center}.chat-header{background:var(--bg-panel);border-bottom:1px solid var(--border);justify-content:space-between;align-items:center;padding:12px 20px;display:flex}.chat-header h3{font-size:16px;font-weight:600}.chat-header-status{color:var(--text-secondary);font-size:12px}.message-list{flex-direction:column;flex:1;gap:4px;padding:16px 20px;display:flex;overflow-y:auto}.messages-start{text-align:center;color:var(--text-secondary);padding:16px;font-size:13px}.message-bubble{word-wrap:break-word;background:var(--bubble-other);max-width:70%;color:var(--bubble-other-text);box-shadow:var(--shadow);border-radius:16px;align-self:flex-start;padding:8px 14px;position:relative}.message-bubble.own{background:var(--bubble-own);color:var(--bubble-own-text);align-self:flex-end}.message-bubble.deleted{opacity:.5;font-style:italic}.message-sender{color:var(--accent);margin-bottom:2px;font-size:12px;font-weight:600}.message-content{white-space:pre-wrap;font-size:15px;line-height:1.4}.deleted-text{opacity:.6;font-style:italic}.message-meta{justify-content:flex-end;align-items:center;gap:6px;margin-top:2px;display:flex}.message-time{opacity:.7;font-size:11px}.message-edited{opacity:.5;font-size:11px;font-style:italic}.message-menu-btn{cursor:pointer;opacity:0;color:inherit;background:0 0;border:none;border-radius:4px;padding:2px 6px;font-size:16px;transition:opacity .15s;position:absolute;top:4px;right:4px}.message-bubble:hover .message-menu-btn{opacity:.7}.message-menu-btn:hover{background:#0000001a;opacity:1!important}.message-menu{background:var(--bg-panel);border:1px solid var(--border);border-radius:var(--radius);box-shadow:var(--shadow);z-index:5;position:absolute;top:-4px;right:32px;overflow:hidden}.message-menu button{text-align:left;cursor:pointer;width:100%;color:var(--text);white-space:nowrap;background:0 0;border:none;padding:8px 16px;font-size:14px;display:block}.message-menu button:hover{background:var(--bg-hover)}.message-edit{flex-direction:column;gap:6px;display:flex}.message-edit input{border:1px solid var(--border);background:var(--bg);color:var(--text);border-radius:6px;outline:none;padding:6px 10px;font-size:14px}.edit-actions{gap:6px;display:flex}.edit-actions button{cursor:pointer;background:var(--bg-hover);color:var(--text);border:none;border-radius:6px;padding:4px 12px;font-size:13px}.edit-actions button:first-child{background:var(--accent);color:#fff}.typing-indicator{color:var(--text-secondary);padding:4px 20px 8px;font-size:13px;font-style:italic}.message-input{background:var(--bg-panel);border-top:1px solid var(--border);align-items:center;gap:8px;padding:12px 16px;display:flex}.message-input.drag-over{background:var(--accent-light)}.message-text-input{border:1px solid var(--border);background:var(--bg);color:var(--text);border-radius:20px;outline:none;flex:1;padding:10px 16px;font-size:15px;transition:border-color .2s}.message-text-input:focus{border-color:var(--accent)}.attach-btn{font-size:20px}.btn-send{background:var(--accent);color:#fff;cursor:pointer;border:none;border-radius:20px;padding:8px 20px;font-size:14px;font-weight:500;transition:background .2s}.btn-send:hover{background:var(--accent-hover)}.btn-send:disabled{opacity:.4;cursor:not-allowed}.btn-icon{cursor:pointer;color:var(--text-secondary);background:0 0;border:none;border-radius:6px;padding:6px;font-size:18px;transition:background .15s}.btn-icon:hover{background:var(--bg-hover);color:var(--text)}.dialog-overlay{z-index:100;background:#0006;justify-content:center;align-items:center;display:flex;position:fixed;inset:0}.dialog{background:var(--bg-panel);border-radius:12px;width:90%;max-width:440px;max-height:80vh;padding:24px;overflow-y:auto;box-shadow:0 20px 60px #0003}.dialog h2{margin-bottom:16px;font-size:20px}.chat-type-toggle{background:var(--bg);border-radius:var(--radius);gap:4px;margin-bottom:16px;padding:4px;display:flex}.chat-type-toggle button{cursor:pointer;color:var(--text-secondary);background:0 0;border:none;border-radius:6px;flex:1;padding:8px;font-size:14px;transition:all .15s}.chat-type-toggle button.active{background:var(--bg-panel);color:var(--text);box-shadow:var(--shadow)}.group-name-input{border:1px solid var(--border);border-radius:var(--radius);background:var(--bg);width:100%;color:var(--text);outline:none;margin-bottom:12px;padding:10px 14px;font-size:14px}.user-select-list{flex-direction:column;gap:4px;max-height:300px;margin-bottom:16px;display:flex;overflow-y:auto}.user-select-item{border-radius:var(--radius);cursor:pointer;align-items:center;gap:10px;padding:8px 12px;transition:background .15s;display:flex}.user-select-item:hover{background:var(--bg-hover)}.user-select-item input{accent-color:var(--accent)}.user-avatar-small{background:var(--accent-light);width:32px;height:32px;color:var(--accent);border-radius:50%;justify-content:center;align-items:center;font-size:14px;font-weight:600;display:flex}.username{color:var(--text-secondary);font-size:13px}.dialog-actions{justify-content:flex-end;gap:8px;display:flex}.dialog-actions button{border-radius:var(--radius);cursor:pointer;border:1px solid var(--border);background:var(--bg);color:var(--text);padding:10px 20px;font-size:14px;transition:all .15s}.dialog-actions button:last-child{background:var(--accent);color:#fff;border-color:var(--accent)}.dialog-actions button:last-child:disabled{opacity:.5;cursor:not-allowed}.settings-page{background:var(--bg);justify-content:center;align-items:flex-start;height:100dvh;padding:40px 20px;display:flex;overflow-y:auto}.settings-container{background:var(--bg-panel);width:100%;max-width:500px;box-shadow:var(--shadow);border-radius:12px;padding:32px}.admin-container{max-width:600px}.settings-header{align-items:center;gap:16px;margin-bottom:24px;display:flex}.settings-header button{cursor:pointer;color:var(--accent);background:0 0;border:none;font-size:15px}.settings-header h1{font-size:22px;font-weight:600}.settings-container form{flex-direction:column;gap:16px;display:flex}.settings-container label{color:var(--text-secondary);flex-direction:column;gap:6px;font-size:14px;display:flex}.settings-container label input{border:1px solid var(--border);border-radius:var(--radius);background:var(--bg);color:var(--text);outline:none;padding:10px 14px;font-size:15px}.settings-container label input:disabled{opacity:.5}.settings-container form button[type=submit]{background:var(--accent);color:#fff;border-radius:var(--radius);cursor:pointer;border:none;padding:10px;font-size:15px}.section-header{justify-content:space-between;align-items:center;margin-bottom:16px;display:flex}.section-header h2{font-size:18px}.section-header button{background:var(--accent);color:#fff;border-radius:var(--radius);cursor:pointer;border:none;padding:8px 16px;font-size:14px}.section-header button:disabled{opacity:.5}.invite-list{flex-direction:column;gap:8px;display:flex}.invite-item{border:1px solid var(--border);border-radius:var(--radius);flex-direction:column;gap:6px;padding:12px 16px;display:flex}.invite-item.used{opacity:.5}.invite-code{align-items:center;gap:8px;display:flex}.invite-code code{background:var(--bg);border-radius:4px;padding:4px 8px;font-family:monospace;font-size:13px}.invite-meta{color:var(--text-secondary);justify-content:space-between;align-items:center;font-size:13px;display:flex}.btn-small{border:1px solid var(--border);cursor:pointer;background:var(--bg);color:var(--text);border-radius:6px;padding:4px 10px;font-size:12px}.btn-small:hover{background:var(--bg-hover)}.btn-danger{color:var(--danger);border-color:var(--danger)}.btn-danger:hover{background:#fef2f2}@media (prefers-color-scheme:dark){.btn-danger:hover{background:#450a0a}}