.thread-list{display:flex;flex-direction:column;height:100%;background:var(--color-background)}.thread-list--loading,.thread-list--error{justify-content:center;align-items:center;padding:var(--spacing-lg)}.thread-list__loading-indicator{display:flex;flex-direction:column;align-items:center;gap:var(--spacing-md);color:var(--color-text-secondary);font-size:.875rem}.thread-list__error-message{color:var(--color-danger);font-size:.875rem;text-align:center}.thread-list__header{display:flex;align-items:center;justify-content:space-between;padding:var(--spacing-sm) var(--spacing-md);border-bottom:1px solid var(--color-border);gap:var(--spacing-sm)}.thread-list__title{font-size:.875rem;font-weight:600;color:var(--color-text);margin:0;flex:1}.thread-list__header-actions{display:flex;align-items:center;gap:var(--spacing-xs)}.thread-list__items{flex:1;overflow-y:auto}.thread-list__empty{flex:1;display:flex;flex-direction:column;align-items:center;justify-content:center;padding:var(--spacing-xl);text-align:center}.thread-list__empty-text{color:var(--color-text);font-size:.875rem;margin:0 0 var(--spacing-sm)}.thread-list__empty-hint{color:var(--color-text-secondary);font-size:.75rem;margin:0;max-width:200px}.thread-list-item{display:flex;align-items:center;gap:6px;min-width:0;margin:2px 6px;padding:2px 8px 2px 6px;border:none;border-radius:var(--border-radius);background:transparent;color:var(--color-text);cursor:pointer;font-family:var(--font-sans);font-size:.8125rem;line-height:1.4;transition:background-color .12s ease}.thread-list-item:hover{background:var(--sidebar-row-hover)}.thread-list-item:focus{outline:none;background:var(--sidebar-row-hover)}.thread-list-item:focus-visible{outline:2px solid var(--color-primary);outline-offset:-2px}.thread-list-item--selected,.thread-list-item--selected:hover{background:var(--sidebar-row-active)}.thread-list-item__status{flex-shrink:0;display:inline-flex;align-items:center;justify-content:center;width:14px;height:14px}.thread-list-item__status-glyph{width:14px;height:14px}.thread-list-item__label{flex:1;min-width:0;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.thread-list-item__timestamp{flex-shrink:0;color:var(--color-text-secondary);font-size:.6875rem;line-height:1.4;text-align:right;white-space:nowrap}.thread-list__collapse-btn{display:flex;align-items:center;justify-content:center;width:28px;height:28px;padding:0;border:none;border-radius:var(--border-radius);background:transparent;color:var(--color-text-secondary);cursor:pointer;transition:all var(--transition-speed) var(--transition-easing)}.thread-list__collapse-btn:hover{background:var(--color-background-secondary);color:var(--color-text)}.thread-list__collapse-btn svg{width:16px;height:16px}.thread-list-header{display:flex;align-items:center;justify-content:space-between;gap:var(--spacing-sm);padding:var(--spacing-sm) var(--spacing-md);position:absolute;top:0;left:0;right:0;z-index:var(--z-sticky);pointer-events:none}.thread-list-header__agent-slot{display:flex;align-items:center;gap:var(--spacing-xs);flex-shrink:0;pointer-events:auto}.thread-list-header__expand-btn,.thread-list-header__new-btn{display:flex;align-items:center;justify-content:center;width:28px;height:28px;padding:0;border:none;border-radius:var(--border-radius);background:transparent;color:var(--color-text-secondary);cursor:pointer;transition:all var(--transition-speed) var(--transition-easing);flex-shrink:0}.thread-list-header__expand-btn:hover,.thread-list-header__new-btn:hover{background:var(--color-background-secondary);color:var(--color-text)}.thread-list-header__expand-btn svg,.thread-list-header__new-btn svg{width:16px;height:16px}.thread-list-header__selector-wrapper{position:relative;flex:1;min-width:0}.thread-list-header__selector{display:flex;align-items:center;gap:var(--spacing-xs);max-width:100%;padding:var(--spacing-xs) var(--spacing-sm);border:1px solid var(--color-border);border-radius:var(--border-radius);background:var(--color-background);color:var(--color-text);cursor:pointer;font-family:var(--font-mono);font-size:.8125rem;transition:all var(--transition-speed) var(--transition-easing);text-align:left}.thread-list-header__selector:hover,.thread-list-header__selector--active{border-color:var(--color-primary);background:var(--color-background-secondary)}.thread-list-header__selector-text{overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.thread-list-header__selector-chevron{flex-shrink:0;color:var(--color-text-secondary);transition:transform var(--transition-speed) var(--transition-easing)}.thread-list-header__selector--active .thread-list-header__selector-chevron{transform:rotate(180deg)}.thread-list-header__dropdown{position:fixed;top:auto;left:auto;right:auto;z-index:var(--z-modal);max-height:400px;min-width:280px;background:var(--color-background);border:1px solid var(--color-border);border-radius:var(--border-radius);box-shadow:var(--shadow-md);display:flex;flex-direction:column;font-family:var(--font-sans);line-height:1.4;animation:header-dropdown-slide .15s ease-out;margin-top:var(--spacing-xs)}@keyframes header-dropdown-slide{0%{opacity:0;transform:translateY(-4px)}to{opacity:1;transform:translateY(0)}}.thread-list-header__dropdown-search{padding:0 8px;border-bottom:0}.thread-list-header__dropdown-title{font-family:var(--font-mono);font-size:11px;font-weight:600;color:var(--color-text-secondary);text-transform:uppercase;letter-spacing:.08em;line-height:1}.thread-list-header__dropdown-items{flex:1;overflow-y:auto;max-height:320px;padding:4px 0 6px}.thread-list-header__dropdown-empty{padding:var(--spacing-lg);text-align:center;color:var(--color-text-secondary);font-size:.875rem}.thread-list-header__dropdown-empty--loading{display:flex;align-items:center;justify-content:center}.thread-list-header__stats-wrapper{position:relative;flex-shrink:0;margin-left:auto}.thread-list-header__stats-wrapper .ui-button{display:flex;align-items:center;gap:var(--spacing-xs)}.thread-list-header__stats-dropdown{position:absolute;top:100%;right:0;z-index:var(--z-dropdown);min-width:200px;background:var(--color-background);border:1px solid var(--color-border);border-radius:var(--border-radius);box-shadow:var(--shadow-md);padding:var(--spacing-sm);margin-top:var(--spacing-xs);animation:header-dropdown-slide .15s ease-out}.thread-list-header__stats-item{display:flex;justify-content:space-between;align-items:center;padding:var(--spacing-xs) var(--spacing-sm);font-size:.75rem}.thread-list-header__stats-label{color:var(--color-text-secondary);font-weight:500;text-transform:uppercase;letter-spacing:.03em}.thread-list-header__stats-value{color:var(--color-text);font-family:var(--font-mono)}.thread-list-header__stats-error{padding:var(--spacing-xs) var(--spacing-sm);background-color:var(--color-danger-bg);color:var(--color-danger);border-radius:var(--border-radius);font-size:.75rem;margin-top:var(--spacing-xs)}.thread-list-header__actions{display:flex;align-items:center;flex-wrap:wrap;gap:var(--spacing-sm);row-gap:var(--spacing-xs);margin-left:auto;position:relative;pointer-events:auto}.thread-list-header__actions .ui-button--primary-light.ui-button--square{width:26px;height:26px;background:transparent;border-color:transparent;color:var(--color-text)}.thread-list-header__actions .ui-button--primary-light.ui-button--square:hover:not(:disabled){background:var(--color-secondary-button);border-color:transparent;color:var(--color-text)}.thread-list-header .ui-spinner--small{width:.75em;height:.75em;border-width:1.5px}.thread-list-header__parent-button{white-space:nowrap}.thread-list-header__linear-indicator{position:absolute;top:2px;right:2px}