.app-header{position:sticky;top:0;z-index:100;height:62px;width:100%;background:rgba(255,255,255,.92);backdrop-filter:blur(14px);-webkit-backdrop-filter:blur(14px);border-bottom:1px solid var(--border-color);padding:0 24px;display:flex;align-items:center;justify-content:space-between;gap:16px}.app-header a{text-decoration:none;color:inherit}.brand-wrapper{display:flex;align-items:center;gap:10px;cursor:pointer;user-select:none;text-decoration:none;color:inherit}.brand-icon{font-size:1.5rem;line-height:1;filter:drop-shadow(0 2px 4px rgba(0, 0, 0, .1))}.brand-title{font-family:var(--font-display);font-size:1.15rem;font-weight:800;color:var(--text-main);letter-spacing:-.02em}.header-nav{display:flex;align-items:center;background:var(--surface-0);border:1px solid var(--border-color);padding:3px;border-radius:var(--radius-full);gap:2px}.header-btn{background:0 0;border:none;font-family:var(--font-sans);font-size:.85rem;font-weight:600;color:var(--text-muted);padding:6px 14px;border-radius:var(--radius-full);cursor:pointer;display:inline-flex;align-items:center;gap:6px;transition:all var(--transition-fast);white-space:nowrap;text-decoration:none}.header-btn:hover{color:var(--text-main);text-decoration:none}.header-btn.active{background:var(--surface-1);color:var(--primary);font-weight:700;box-shadow:var(--shadow-sm);text-decoration:none}.header-btn.is-locked{opacity:.6;cursor:not-allowed}.header-right-actions{display:flex;align-items:center;gap:8px}.header-btn-subtle{background:0 0;border:1px solid transparent;font-size:.825rem;font-weight:600;color:var(--text-muted);padding:6px 12px;border-radius:var(--radius-full);cursor:pointer;transition:all var(--transition-fast);display:inline-flex;align-items:center;gap:4px}.header-btn-subtle:hover{background:var(--surface-0);color:var(--text-main);border-color:var(--border-color)}.icon-btn{background:0 0;border:1px solid var(--border-color);width:34px;height:34px;border-radius:50%;cursor:pointer;display:flex;align-items:center;justify-content:center;color:var(--text-muted);font-size:.9rem;transition:all var(--transition-fast)}.icon-btn:hover{background:var(--surface-0);color:var(--text-main)}.header-user-btn{background:var(--surface-1);border:1px solid var(--border-color);padding:4px 10px 4px 5px;border-radius:var(--radius-full);display:flex;align-items:center;gap:8px;cursor:pointer;font-size:.825rem;font-weight:600;color:var(--text-main);transition:all var(--transition-fast);text-decoration:none}.header-user-btn:hover{border-color:var(--primary-border);box-shadow:var(--shadow-sm);text-decoration:none}.header-user-avatar{width:24px;height:24px;border-radius:50%;background:var(--surface-0);display:flex;align-items:center;justify-content:center;font-size:.85rem}.uid-chip{font-family:var(--font-mono);font-size:.7rem;background:var(--surface-0);color:var(--text-muted);padding:1px 6px;border-radius:var(--radius-full)}.reconnect-banner{background:#fffbeb;border-bottom:1px solid #fef3c7;color:#b45309;padding:6px 16px;text-align:center;font-size:.8rem;font-weight:600;display:flex;align-items:center;justify-content:center;gap:8px}@media (max-width:768px){.app-header{padding:0 12px;height:56px}.brand-title,.header-btn-subtle{display:none}.header-btn span{font-size:.775rem}.header-nav{padding:2px}.header-btn{padding:5px 8px}}