.chat-shell {
  --rail-left: minmax(200px, 240px);
  --rail-right: minmax(260px, 320px);
  display: grid;
  grid-template-columns: var(--rail-left) minmax(0, 1fr) var(--rail-right);
  min-height: 0;
  flex: 1;
}

/* 侧栏收起：宽度归零，主区仍固定在第 2 列，卡片直接变宽 */
.chat-shell.is-left-hidden {
  --rail-left: 0px;
}

.chat-shell.is-left-hidden .chat-rail {
  display: none;
}

.chat-shell.is-right-hidden {
  --rail-right: 0px;
}

.chat-shell.is-right-hidden .chat-context {
  display: none;
}

/* 侧栏边缘的收起/展开小把手 */
.chat-rail-toggle,
.chat-rail-reopen {
  position: absolute;
  top: 10px;
  z-index: 4;
  width: 18px;
  height: 42px;
  display: grid;
  place-items: center;
  padding: 0;
  border: 1px solid var(--st-border-strong);
  border-radius: 8px;
  background: var(--st-surface);
  color: var(--st-muted);
  font: inherit;
  font-size: 13px;
  line-height: 1;
  cursor: pointer;
  opacity: 0.75;
}

.chat-rail-toggle:hover,
.chat-rail-toggle:focus-visible,
.chat-rail-reopen:hover,
.chat-rail-reopen:focus-visible {
  opacity: 1;
  color: var(--st-accent);
  border-color: var(--st-accent);
  background: var(--st-accent-soft);
  outline: none;
}

.chat-rail-reopen[hidden] {
  display: none;
}

.chat-rail-toggle-left {
  right: -9px;
}

.chat-rail-toggle-right {
  left: -9px;
}

.chat-rail-reopen-left {
  left: 2px;
}

.chat-rail-reopen-right {
  right: 2px;
}

.chat-rail {
  grid-column: 1;
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 10px;
  min-height: 0;
  padding: 12px;
  border-right: 1px solid var(--st-border);
  background: color-mix(in srgb, var(--st-surface) 88%, var(--st-bg));
}

.chat-path {
  margin: 0;
}

.chat-path .path-bar-list {
  display: flex;
  flex-wrap: wrap;
  gap: 4px;
  list-style: none;
  margin: 0;
  padding: 0;
  font-size: 12px;
  color: var(--st-muted);
}

.chat-path .path-bar-item {
  display: inline-flex;
  align-items: center;
  gap: 4px;
}

.chat-path .path-bar-item:not(:last-child)::after {
  content: "›";
  margin-left: 4px;
  color: var(--st-faint);
}

.chat-path button,
.chat-path .path-bar-current {
  border: 0;
  background: transparent;
  color: inherit;
  padding: 0;
  font: inherit;
  cursor: pointer;
}

.chat-path button:hover {
  color: var(--st-accent);
}

.chat-path .path-bar-current {
  color: var(--st-text);
  font-weight: 600;
  cursor: default;
}

.chat-rail-actions {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.chat-rail-list {
  flex: 1;
  min-height: 0;
  overflow: auto;
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.chat-rail-item {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 8px;
  width: 100%;
  text-align: left;
  border: 1px solid transparent;
  border-radius: 8px;
  background: transparent;
  color: var(--st-text);
  padding: 8px 10px;
  cursor: pointer;
  font: inherit;
}

.chat-rail-item:hover {
  background: var(--st-accent-soft);
}

.chat-rail-item.active {
  border-color: color-mix(in srgb, var(--st-accent) 45%, var(--st-border));
  background: var(--st-accent-soft);
}

.chat-rail-item-main {
  min-width: 0;
  flex: 1;
}

.chat-rail-item-title {
  display: block;
  font-weight: 600;
  font-size: 13px;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.chat-rail-item-meta {
  display: block;
  margin-top: 2px;
  font-size: 11px;
  color: var(--st-muted);
}

.chat-rail-item-actions {
  display: flex;
  flex-shrink: 0;
  align-items: center;
  gap: 2px;
}

.chat-rail-item-copy,
.chat-rail-item-del {
  flex-shrink: 0;
  border: 0;
  background: transparent;
  color: var(--st-faint);
  cursor: pointer;
  padding: 2px 4px;
  font: inherit;
  font-size: 12px;
}

.chat-rail-item-copy:hover,
.chat-rail-item-copy:focus-visible {
  color: var(--st-text);
}

.chat-rail-item-del:hover,
.chat-rail-item-del:focus-visible {
  color: var(--st-danger);
}

.chat-rail-item-main:focus-visible,
.chat-rail-item-copy:focus-visible,
.chat-rail-item-del:focus-visible,
.st-btn:focus-visible {
  outline: 2px solid var(--st-accent);
  outline-offset: 2px;
}

.chat-rail-note {
  margin: 0;
  font-size: 11px;
  color: var(--st-faint);
  line-height: 1.4;
}

.chat-main {
  grid-column: 2;
  position: relative;
  display: flex;
  flex-direction: column;
  min-width: 0;
  min-height: 0;
  background: var(--st-bg);
}

.chat-room {
  position: relative;
  display: flex;
  flex-direction: column;
  min-height: 0;
  flex: 1;
}

.chat-temp-mark {
  position: absolute;
  inset: 0 0 88px;
  z-index: 2;
  display: flex;
  align-items: flex-start;
  justify-content: center;
  padding-top: 11vh;
  margin: 0;
  pointer-events: none;
  font-family: var(--st-font-read);
  font-size: clamp(28px, 4vw, 42px);
  font-weight: 600;
  letter-spacing: 0.12em;
  color: color-mix(in srgb, var(--st-text) 14%, transparent);
  user-select: none;
}

.chat-temp-mark[hidden] {
  display: none;
}

.chat-profile-label {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 12px;
  color: var(--st-muted);
}

.chat-profile-label select {
  min-width: 140px;
  max-width: 220px;
  border: 1px solid var(--st-border-strong);
  border-radius: 6px;
  background: var(--st-surface);
  color: var(--st-text);
  padding: 4px 8px;
  font: inherit;
}

.chat-context {
  grid-column: 3;
  position: relative;
  display: flex;
  flex-direction: column;
  min-width: 0;
  min-height: 0;
  border-left: 1px solid var(--st-border);
  background: color-mix(in srgb, var(--st-surface) 92%, var(--st-bg));
}

.chat-context-head {
  flex-shrink: 0;
  padding: 10px 14px 8px;
  border-bottom: 1px solid var(--st-border);
}

.chat-context-sub {
  margin: 0;
  font-size: 11px;
  color: var(--st-muted);
  line-height: 1.35;
}

.chat-shell-editor {
  display: grid;
  gap: 10px;
  padding: 12px 14px 16px;
  overflow: auto;
  min-height: 0;
  flex: 1;
  align-content: start;
}

.chat-shell-editor label {
  display: grid;
  gap: 4px;
  font-size: 12px;
  color: var(--st-muted);
}

/* 种子历史是条目编辑器（不是 textarea），包一层跟其它字段同列的标题 + 控件 */
.chat-shell-editor .chat-shell-field {
  display: grid;
  gap: 4px;
  font-size: 12px;
  color: var(--st-muted);
}
.chat-shell-history {
  min-width: 0;
}

.chat-shell-editor input,
.chat-shell-editor textarea {
  border: 1px solid var(--st-border-strong);
  border-radius: 6px;
  background: var(--st-surface);
  color: var(--st-text);
  padding: 6px 8px;
  font: inherit;
  resize: vertical;
}

.chat-shell-editor input:disabled,
.chat-shell-editor textarea:disabled {
  opacity: 0.65;
  background: color-mix(in srgb, var(--st-bg) 70%, var(--st-surface));
}

.chat-shell-editor-actions {
  display: flex;
  justify-content: flex-end;
  gap: 8px;
  padding-top: 4px;
}

/* 右侧面板的两个页签：上下文 / 保留统计 */
.chat-context-tabs {
  flex-shrink: 0;
  display: flex;
  gap: 2px;
  padding: 8px 14px 0;
  border-bottom: 1px solid var(--st-border);
}

.chat-context-tab {
  border: 1px solid transparent;
  border-bottom: 0;
  border-radius: 6px 6px 0 0;
  background: transparent;
  color: var(--st-muted);
  font: inherit;
  font-size: 12px;
  line-height: 1;
  padding: 7px 10px;
  cursor: pointer;
}

.chat-context-tab:hover,
.chat-context-tab:focus-visible {
  color: var(--st-text);
  background: color-mix(in srgb, var(--st-muted) 10%, transparent);
  outline: none;
}

.chat-context-tab.is-active {
  border-color: var(--st-border);
  background: var(--st-surface);
  color: var(--st-text);
  font-weight: 600;
  margin-bottom: -1px;
}

.chat-shell-editor[hidden],
.chat-keep-stats[hidden] {
  display: none !important;
}

/* 保留统计：条状图，按次数降序 */
.chat-keep-stats {
  flex: 1;
  min-height: 0;
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding: 12px 14px 16px;
  overflow: auto;
}

.chat-keep-stats-hint {
  margin: 0;
  font-size: 11px;
  line-height: 1.4;
  color: var(--st-muted);
}

.chat-keep-stats-list {
  display: grid;
  gap: 10px;
  align-content: start;
}

.chat-keep-bar {
  display: grid;
  gap: 4px;
}

.chat-keep-bar-head {
  display: flex;
  align-items: baseline;
  gap: 8px;
  min-width: 0;
}

.chat-keep-bar-name {
  flex: 1;
  min-width: 0;
  font-size: 12px;
  font-weight: 600;
  color: var(--st-text);
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.chat-keep-bar-count {
  flex-shrink: 0;
  font-size: 11px;
  font-variant-numeric: tabular-nums;
  color: var(--st-muted);
}

.chat-keep-bar-track {
  height: 8px;
  border-radius: 99px;
  background: color-mix(in srgb, var(--st-muted) 14%, transparent);
  overflow: hidden;
}

.chat-keep-bar-fill {
  height: 100%;
  border-radius: 99px;
  background: color-mix(in srgb, var(--st-accent) 72%, var(--st-muted));
}

.chat-keep-bar-model {
  margin: 0;
  font-size: 11px;
  color: var(--st-faint);
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.chat-keep-stats-foot {
  margin-top: auto;
  display: flex;
  justify-content: flex-end;
}

.chat-keep-stats-foot .st-btn {
  font-size: 11px;
  padding: 4px 8px;
}

/* —— 模型竞技场：用户气泡 + 横向回复卡片 —— */
.chat-arena {
  position: relative;
  z-index: 1;
  flex: 1;
  min-height: 0;
  display: flex;
  flex-direction: column;
  overflow: hidden;
  background: transparent;
  border-bottom: 1px solid var(--st-border);
}

.chat-arena.is-empty {
  align-items: center;
  justify-content: center;
  border-bottom: 0;
}

.chat-add-card {
  position: relative;
  z-index: 3;
  width: min(280px, 70%);
  height: min(360px, 62%);
  min-height: 180px;
  border: 1px dashed var(--st-border-strong);
  border-radius: 12px;
  background: color-mix(in srgb, var(--st-surface) 72%, transparent);
  color: color-mix(in srgb, var(--st-text) 28%, transparent);
  font: inherit;
  font-size: 64px;
  font-weight: 400;
  line-height: 1;
  cursor: pointer;
}

.chat-add-card:hover,
.chat-add-card:focus-visible {
  border-color: var(--st-accent);
  color: var(--st-accent);
  background: var(--st-accent-soft);
  outline: none;
}

.chat-composer-row {
  display: flex;
  align-items: flex-end;
  gap: 8px;
  min-width: 0;
}

.chat-more {
  position: relative;
  align-self: center;
  flex: 0 0 auto;
}

.chat-more[hidden] {
  display: none !important;
}

.chat-composer:has(.chat-more[open]) {
  z-index: 6;
}

.chat-more-sum {
  list-style: none;
  cursor: pointer;
  user-select: none;
  box-sizing: border-box;
  width: 32px;
  height: 32px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border: 1px solid transparent;
  border-radius: 8px;
  background: transparent;
  color: var(--st-muted);
}

.chat-more-sum::-webkit-details-marker {
  display: none;
}

.chat-more-sum::marker {
  content: "";
}

.chat-more-sum:hover,
.chat-more[open] > .chat-more-sum {
  color: var(--st-accent);
  background: var(--st-accent-soft);
  border-color: transparent;
}

.hamburger-icon {
  display: block;
  width: 14px;
  height: 11px;
  background:
    linear-gradient(currentColor, currentColor) 0 0 / 100% 1.5px no-repeat,
    linear-gradient(currentColor, currentColor) 0 50% / 100% 1.5px no-repeat,
    linear-gradient(currentColor, currentColor) 0 100% / 100% 1.5px no-repeat;
}

.chat-more-panel {
  position: absolute;
  left: 0;
  bottom: calc(100% + 6px);
  z-index: 8;
  min-width: 168px;
  padding: 4px;
  border: 1px solid var(--st-border);
  border-radius: 8px;
  background: var(--st-surface);
  box-shadow: 0 12px 32px color-mix(in srgb, var(--st-text) 14%, transparent);
  display: flex;
  flex-direction: column;
  gap: 1px;
}

.chat-more-item {
  border: 0;
  border-radius: 6px;
  background: transparent;
  color: var(--st-text);
  font: inherit;
  font-size: 13px;
  text-align: left;
  padding: 7px 10px;
  cursor: pointer;
}

.chat-more-item:hover,
.chat-more-item:focus-visible {
  background: var(--st-accent-soft);
  outline: none;
}

.chat-arena-empty {
  margin: auto;
  padding: 24px 16px;
  text-align: center;
  color: var(--st-muted);
  font-size: 13px;
  line-height: 1.5;
  max-width: 28rem;
}

.chat-arena-stream {
  flex: 1;
  min-height: 0;
  overflow-x: hidden;
  overflow-y: auto;
  padding: 16px;
  display: flex;
  flex-direction: column;
  gap: 22px;
  scrollbar-width: none;
}

.chat-arena-stream::-webkit-scrollbar {
  width: 0;
  height: 0;
}

.chat-arena-idle {
  margin: 0;
  padding: 8px 0 0;
  text-align: center;
  color: var(--st-faint);
  font-size: 13px;
  line-height: 1.5;
}

.chat-turn {
  display: flex;
  flex-direction: column;
  gap: 8px;
  min-width: 0;
}

.chat-user-row {
  display: flex;
  justify-content: flex-end;
  align-items: flex-start;
  flex: 0 0 auto;
  min-height: 0;
}

.chat-user-bubble {
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  gap: 2px;
  width: fit-content;
  max-width: min(92%, 42rem);
  min-height: 0;
  height: auto;
  box-sizing: border-box;
  padding: 8px 12px 6px;
  border-radius: 14px;
  border-bottom-right-radius: 4px;
  border: 1px solid #93c5fd;
  background: linear-gradient(180deg, #eff6ff 0%, #dbeafe 100%);
  box-shadow: 0 1px 2px rgba(0, 0, 0, 0.04);
  color: #1e293b;
}

.chat-user-body {
  width: 100%;
  white-space: pre-wrap;
  word-break: break-word;
  line-height: 1.55;
  font-size: 14px;
}

.chat-user-bubble.is-editing {
  width: min(92%, 42rem);
}

.chat-user-foot,
.chat-user-edit-bar {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  flex-wrap: wrap;
  gap: 2px;
  width: 100%;
}

.chat-turn-variants {
  display: inline-flex;
  align-items: center;
  gap: 0;
  margin-right: auto;
}

.chat-turn-variant-count {
  min-width: 2.2rem;
  text-align: center;
  font-size: 11px;
  font-variant-numeric: tabular-nums;
  color: #64748b;
}

.chat-user-foot .chat-nav-btn {
  width: 22px;
  height: 22px;
  border-radius: 6px;
  color: #64748b;
}

.chat-user-act {
  border: 0;
  background: transparent;
  color: #475569;
  font: inherit;
  font-size: 12px;
  line-height: 1;
  padding: 3px 6px;
  border-radius: 6px;
  cursor: pointer;
}

.chat-user-act:hover,
.chat-user-act:focus-visible {
  color: #1d4ed8;
  background: rgba(255, 255, 255, 0.72);
  outline: none;
}

.chat-user-act.is-primary {
  color: #1d4ed8;
  font-weight: 600;
}

.chat-user-act:disabled {
  opacity: 0.4;
  cursor: default;
}

.chat-user-edit {
  width: 100%;
  min-height: 4.5rem;
  max-height: 320px;
  box-sizing: border-box;
  resize: vertical;
  border: 1px solid #93c5fd;
  border-radius: 8px;
  background: #fff;
  color: #1e293b;
  font: inherit;
  font-size: 14px;
  line-height: 1.55;
  padding: 8px;
}

.chat-user-edit:focus {
  outline: 2px solid #bfdbfe;
  outline-offset: 1px;
}

.chat-user-edit-hint {
  margin: 0;
  width: 100%;
  font-size: 11px;
  line-height: 1.3;
  color: #64748b;
}

.chat-bubble-time {
  font-size: 10px;
  line-height: 1.2;
  color: #64748b;
}

.chat-strip-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
  min-height: 28px;
}

.chat-strip-hint {
  font-size: 11px;
  color: var(--st-faint);
}

/* 本轮有多个失败时，一键重跑全部失败窗口；已成功的卡片不动 */
.chat-retry-all {
  margin-left: auto;
  border: 1px solid var(--st-border-strong);
  border-radius: 6px;
  background: var(--st-surface);
  color: var(--st-text);
  font: inherit;
  font-size: 11px;
  font-weight: 500;
  padding: 3px 8px;
  cursor: pointer;
}

.chat-retry-all:hover,
.chat-retry-all:focus-visible {
  border-color: var(--st-accent);
  background: var(--st-accent-soft);
  outline: none;
}

.chat-retry-all:disabled {
  opacity: 0.5;
  cursor: default;
}

.chat-strip-nav {
  display: flex;
  align-items: center;
  gap: 4px;
}

.chat-strip-idx {
  min-width: 3.2rem;
  text-align: center;
  font-size: 11px;
  font-variant-numeric: tabular-nums;
  color: var(--st-muted);
}

.chat-nav-btn {
  width: 28px;
  height: 28px;
  border: 1px solid transparent;
  border-radius: 8px;
  background: transparent;
  color: var(--st-muted);
  font: inherit;
  font-size: 14px;
  line-height: 1;
  cursor: pointer;
}

.chat-nav-btn:hover,
.chat-nav-btn:focus-visible {
  color: var(--st-accent);
  background: var(--st-accent-soft);
  outline: none;
}

.chat-nav-btn:disabled {
  opacity: 0.35;
  cursor: default;
  background: transparent;
  color: var(--st-faint);
}

.chat-reply-track {
  --card-gap: 10px;
  --card-peek: 36px;
  --card-min-h: 120px;
  display: flex;
  align-items: flex-start;
  gap: var(--card-gap);
  overflow-x: auto;
  padding-bottom: 2px;
  cursor: grab;
  scrollbar-width: none;
  touch-action: none;
  overscroll-behavior-x: contain;
}

.chat-reply-track::-webkit-scrollbar {
  display: none;
}

.chat-reply-track.is-dragging,
.chat-reply-track.is-dragging * {
  cursor: grabbing;
  user-select: none;
  -webkit-user-select: none;
}

.chat-reply-card {
  flex: 0 0 calc((100% - var(--card-gap) - var(--card-peek)) / 2);
  width: calc((100% - var(--card-gap) - var(--card-peek)) / 2);
  display: flex;
  flex-direction: column;
  min-width: 0;
  min-height: var(--card-min-h);
  border: 1px solid var(--st-border);
  border-radius: 8px;
  background: var(--st-surface);
}

.chat-reply-track[data-count="1"] .chat-reply-card {
  flex-basis: 100%;
  width: 100%;
}

.chat-reply-card.is-collapsed,
.chat-reply-card.is-capped {
  overflow: hidden;
}

.chat-reply-card:is(.is-collapsed, .is-capped) .chat-reply-card-body {
  flex: 1 1 auto;
  min-height: 0;
  overflow: hidden;
}

.chat-reply-card:is(.is-collapsed, .is-capped) .chat-reply-card-text {
  flex: 1 1 auto;
  min-height: 0;
  height: 100%;
  overflow-x: hidden;
  overflow-y: auto;
  scrollbar-width: none;
}

.chat-reply-card:is(.is-collapsed, .is-capped) .chat-reply-card-text::-webkit-scrollbar {
  width: 0;
}

.chat-reply-card-text.is-vscroll,
.chat-arena-stream.is-vscroll {
  scrollbar-width: thin;
  scrollbar-color: color-mix(in srgb, var(--st-muted) 42%, transparent) transparent;
}

.chat-reply-card-text.is-vscroll::-webkit-scrollbar,
.chat-arena-stream.is-vscroll::-webkit-scrollbar {
  width: 6px;
}

.chat-reply-card-text.is-vscroll::-webkit-scrollbar-thumb,
.chat-arena-stream.is-vscroll::-webkit-scrollbar-thumb {
  background: color-mix(in srgb, var(--st-muted) 45%, transparent);
  border-radius: 99px;
}

/* 分卡片：正文没在顶端就一直露着滚动条，滚回顶端才收 */
.chat-reply-card:is(.is-collapsed, .is-capped) .chat-reply-card-text.is-scrolled,
.chat-reply-card:is(.is-collapsed, .is-capped) .chat-reply-card-text.is-vscroll {
  scrollbar-width: thin;
  scrollbar-color: color-mix(in srgb, var(--st-muted) 42%, transparent) transparent;
}

.chat-reply-card:is(.is-collapsed, .is-capped) .chat-reply-card-text.is-scrolled::-webkit-scrollbar,
.chat-reply-card:is(.is-collapsed, .is-capped) .chat-reply-card-text.is-vscroll::-webkit-scrollbar {
  width: 6px;
}

.chat-reply-card:is(.is-collapsed, .is-capped) .chat-reply-card-text.is-scrolled::-webkit-scrollbar-thumb,
.chat-reply-card:is(.is-collapsed, .is-capped) .chat-reply-card-text.is-vscroll::-webkit-scrollbar-thumb {
  background: color-mix(in srgb, var(--st-muted) 45%, transparent);
  border-radius: 99px;
}

.chat-reply-card.is-selected {
  border-color: var(--st-accent);
  background: color-mix(in srgb, var(--st-accent-soft) 55%, var(--st-surface));
}

.chat-reply-card.is-error {
  border-color: color-mix(in srgb, var(--st-danger) 45%, var(--st-border));
}

.chat-reply-card-head {
  flex-shrink: 0;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
  padding: 8px 10px;
  border-bottom: 1px solid var(--st-border);
}

.chat-reply-card-titles {
  min-width: 0;
}

.chat-reply-card-actions {
  display: flex;
  align-items: center;
  gap: 6px;
  flex-shrink: 0;
}

.chat-reply-card-name {
  display: block;
  font-size: 13px;
  font-weight: 650;
  color: var(--st-text);
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.chat-reply-card-model {
  display: block;
  margin-top: 1px;
  font-size: 11px;
  color: var(--st-muted);
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

/* 盲测：编号当按钮用，点一下只揭示这一张卡 */
.chat-reply-card-name.is-blind {
  display: block;
  max-width: 100%;
  padding: 1px 8px;
  border: 1px solid var(--st-border);
  border-radius: 999px;
  background: color-mix(in srgb, var(--st-muted) 8%, transparent);
  font-size: 12px;
  font-weight: 600;
  color: var(--st-muted);
  text-align: left;
  cursor: pointer;
  transition: color 0.12s ease, border-color 0.12s ease, background 0.12s ease;
}

.chat-reply-card-name.is-blind:hover {
  color: var(--st-text);
  border-color: color-mix(in srgb, var(--st-accent) 50%, var(--st-border));
}

.chat-reply-card-name.is-blind.is-revealed {
  color: var(--st-text);
  border-color: color-mix(in srgb, var(--st-accent) 50%, var(--st-border));
  background: var(--st-accent-soft);
}

.chat-reply-card-name.is-blind:focus-visible {
  outline: 2px solid var(--st-accent);
  outline-offset: 1px;
}

.chat-reply-card-model.is-revealed {
  font-size: 12px;
  font-weight: 600;
  color: var(--st-text);
}

.chat-reply-card-body {
  flex: 1 1 auto;
  min-height: 0;
  display: flex;
  flex-direction: column;
  padding: 10px;
  font-size: 13px;
  line-height: 1.55;
  word-break: break-word;
}

.chat-reply-card-body.is-error {
  color: var(--st-danger);
}

.chat-reply-card-body.is-pending {
  color: var(--st-faint);
}

.chat-reply-card-text {
  min-width: 0;
  cursor: text;
  user-select: text;
  -webkit-user-select: text;
  touch-action: auto;
}

/* 关闭复制：卡片任意处都能拖动滚动，正文不再选中 */
.chat-arena.is-copy-off .chat-reply-card-text,
.chat-arena.is-copy-off .chat-reply-card-text *,
.chat-arena.is-copy-off .chat-reply-card-body {
  cursor: grab;
  user-select: none;
  -webkit-user-select: none;
  touch-action: none;
}

.chat-reply-track.is-dragging .chat-reply-card-text,
.chat-reply-track.is-dragging .chat-reply-card-text * {
  cursor: grabbing;
}

.chat-reply-card-text .md-p {
  margin: 0 0 0.55em;
  line-height: 1.55;
}

.chat-reply-card-text .md-p:last-child {
  margin-bottom: 0;
}

.chat-reply-card-text .md-h {
  margin: 0.7em 0 0.35em;
  font-weight: 650;
  line-height: 1.35;
}

.chat-reply-card-text .md-h:first-child {
  margin-top: 0;
}

.chat-reply-card-text h1.md-h { font-size: 1.25em; }
.chat-reply-card-text h2.md-h { font-size: 1.15em; }
.chat-reply-card-text h3.md-h,
.chat-reply-card-text h4.md-h,
.chat-reply-card-text h5.md-h,
.chat-reply-card-text h6.md-h { font-size: 1.05em; }

.chat-reply-card-text .md-ul,
.chat-reply-card-text .md-ol {
  margin: 0.35em 0 0.55em;
  padding-left: 1.35em;
}

.chat-reply-card-text .md-quote {
  margin: 0.45em 0;
  padding: 0.15em 0 0.15em 0.75em;
  border-left: 3px solid color-mix(in srgb, var(--st-accent) 45%, var(--st-border));
  color: var(--st-muted);
}

.chat-reply-card-text .md-pre {
  margin: 0.45em 0;
  padding: 8px 10px;
  overflow-x: hidden;
  overflow-wrap: anywhere;
  word-break: break-word;
  white-space: pre-wrap;
  border-radius: 8px;
  border: 1px solid var(--st-border);
  background: color-mix(in srgb, var(--st-bg) 80%, var(--st-surface));
  font-size: 12px;
  line-height: 1.45;
}

.chat-reply-card-text .md-code {
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 0.92em;
  padding: 0.05em 0.35em;
  border-radius: 4px;
  background: color-mix(in srgb, var(--st-bg) 70%, var(--st-surface));
}

.chat-reply-card-text .md-a {
  color: var(--st-accent);
  text-decoration: underline;
  text-underline-offset: 2px;
}

.chat-reply-card-text .md-hr {
  border: none;
  border-top: 1px solid var(--st-border);
  margin: 0.75em 0;
}

.chat-reply-card-text .md-table-wrap {
  margin: 0.55em 0;
  overflow-x: auto;
}

.chat-reply-card-text .md-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.92em;
  line-height: 1.45;
}

.chat-reply-card-text .md-table th,
.chat-reply-card-text .md-table td {
  border: 1px solid var(--st-border);
  padding: 0.35em 0.55em;
  text-align: left;
  vertical-align: top;
}

.chat-reply-card-text .md-table th {
  font-weight: 650;
  background: color-mix(in srgb, var(--st-surface) 88%, var(--st-accent));
}

.chat-reply-card-foot {
  flex-shrink: 0;
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 8px;
  padding: 0 10px 8px;
}

.chat-reply-card-foot:not(:has(button:not([hidden]), .chat-select-btn.is-on)) {
  display: none;
}

.chat-expand-btn {
  margin-right: auto;
  border: 0;
  background: transparent;
  color: var(--st-muted);
  font: inherit;
  font-size: 12px;
  padding: 4px 0;
  cursor: pointer;
}

.chat-expand-btn:hover,
.chat-expand-btn:focus-visible {
  color: var(--st-accent);
  outline: none;
}

.chat-copy-btn,
.chat-remove-btn,
.chat-retry-btn,
.chat-regen-btn,
.chat-select-btn {
  border: 1px solid var(--st-border-strong);
  border-radius: 6px;
  background: var(--st-surface);
  color: var(--st-text);
  font: inherit;
  font-size: 12px;
  font-weight: 500;
  padding: 4px 8px;
  cursor: pointer;
}

.chat-copy-btn:hover,
.chat-remove-btn:hover,
.chat-retry-btn:hover,
.chat-regen-btn:hover,
.chat-select-btn:hover,
.chat-copy-btn:focus-visible,
.chat-remove-btn:focus-visible,
.chat-retry-btn:focus-visible,
.chat-regen-btn:focus-visible,
.chat-select-btn:focus-visible {
  border-color: var(--st-accent);
  background: var(--st-accent-soft);
  outline: none;
}

.chat-regen-btn:disabled {
  opacity: 0.5;
  cursor: default;
}

.chat-regen-btn:disabled:hover {
  border-color: var(--st-border-strong);
  background: var(--st-surface);
}

/* 失败卡片上的重试按钮：用强调色标出来 */
.chat-retry-btn {
  border-color: var(--st-accent);
  color: var(--st-text);
  font-weight: 600;
}

.chat-select-btn.is-on {
  border-color: var(--st-accent);
  background: var(--st-accent-soft);
  color: var(--st-text);
  font-weight: 650;
}

/* 思维链：默认折叠成一行，点开才铺开正文 */
.chat-think {
  margin: 0 0 8px;
  border: 1px dashed var(--st-border-strong);
  border-radius: 6px;
  background: color-mix(in srgb, var(--st-bg) 80%, transparent);
  font-size: 12px;
}

.chat-think-summary {
  cursor: pointer;
  padding: 5px 8px;
  color: var(--st-muted);
  user-select: none;
  -webkit-user-select: none;
  font-size: 12px;
}

.chat-think-summary:hover,
.chat-think-summary:focus-visible {
  color: var(--st-text);
  outline: none;
}

.chat-think[open] .chat-think-summary {
  border-bottom: 1px dashed var(--st-border);
}

.chat-think-body {
  padding: 8px;
  color: var(--st-muted);
}

/* 关闭复制时整张卡都能拖，但折叠条仍要能点 */
.chat-arena.is-copy-off .chat-think-summary {
  cursor: pointer;
}

.chat-composer {
  position: relative;
  z-index: 1;
  padding: 10px 16px 14px;
  border-top: 1px solid var(--st-border);
  background: var(--st-surface);
  display: grid;
  gap: 6px;
}

.chat-input-shell {
  position: relative;
  flex: 1 1 auto;
  min-width: 0;
  display: flex;
  align-items: flex-end;
  gap: 8px;
  min-height: 36px;
  border: 1px solid var(--st-border-strong);
  border-radius: 10px;
  padding: 4px 6px 4px 10px;
  background: var(--st-bg);
  transition: border-color 0.12s ease, box-shadow 0.12s ease;
}

.chat-input-shell:focus-within {
  border-color: var(--st-accent);
  box-shadow: 0 0 0 2px var(--st-accent-soft);
}

.chat-input-shell textarea {
  flex: 1 1 auto;
  min-width: 0;
  min-height: 28px;
  max-height: min(42vh, 280px);
  border: 0;
  border-radius: 0;
  background: transparent;
  color: var(--st-text);
  padding: 6px 4px;
  margin: 0;
  font: inherit;
  line-height: 1.5;
  resize: none;
  field-sizing: content;
}

.chat-input-shell textarea:focus {
  outline: none;
}

.chat-shell-actions {
  flex-shrink: 0;
  display: flex;
  align-items: center;
  gap: 6px;
  padding-bottom: 0;
}

.chat-btn-icon {
  box-sizing: border-box;
  width: 28px;
  min-width: 28px;
  height: 28px;
  padding: 0;
  border: 1px solid var(--st-border-strong);
  border-radius: 8px;
  background: var(--st-surface);
  color: var(--st-text);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
}

.chat-btn-icon:hover:not(:disabled) {
  border-color: var(--st-accent);
  background: var(--st-accent-soft);
}

.chat-btn-icon:disabled {
  opacity: 0.55;
  cursor: not-allowed;
}

.chat-btn-icon-primary {
  background: var(--st-accent);
  border-color: var(--st-accent);
  color: #fff;
}

.chat-btn-icon-primary:hover:not(:disabled) {
  filter: brightness(0.96);
  background: var(--st-accent);
  border-color: var(--st-accent);
}

.chat-send-icon {
  display: block;
}

.chat-status {
  margin: 0;
  font-size: 12px;
  color: var(--st-muted);
}

.chat-status.error {
  color: var(--st-danger);
}

.st-btn[hidden] {
  display: none !important;
}

.st-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 4px;
  border: 1px solid var(--st-border-strong);
  border-radius: 7px;
  background: var(--st-surface);
  color: var(--st-text);
  padding: 6px 10px;
  font: inherit;
  font-size: 13px;
  font-weight: 500;
  cursor: pointer;
}

.st-btn:hover {
  border-color: var(--st-accent);
  background: var(--st-accent-soft);
}

.st-btn:disabled {
  opacity: 0.55;
  cursor: not-allowed;
}

.st-btn-primary {
  border-color: color-mix(in srgb, var(--st-accent) 55%, var(--st-border-strong));
  background: var(--st-accent-soft);
  color: var(--st-text);
  font-weight: 600;
}

.chat-dialog {
  border: 1px solid var(--st-border-strong);
  border-radius: 12px;
  padding: 0;
  background: var(--st-surface);
  color: var(--st-text);
  max-width: min(420px, 92vw);
}

.chat-dialog-wide {
  max-width: min(720px, 94vw);
  width: 94vw;
}

.chat-dialog::backdrop {
  background: rgba(0, 0, 0, 0.35);
}

.chat-dialog form,
.chat-dialog > div {
  display: grid;
  gap: 10px;
  padding: 16px;
}

.chat-dialog h3 {
  margin: 0;
  font-size: 16px;
}

.chat-dialog-hint {
  margin: 0;
  font-size: 12px;
  color: var(--st-muted);
}

.chat-dialog label {
  display: grid;
  gap: 4px;
  font-size: 12px;
  color: var(--st-muted);
}

.chat-dialog input {
  border: 1px solid var(--st-border-strong);
  border-radius: 6px;
  background: var(--st-bg);
  color: var(--st-text);
  padding: 6px 8px;
  font: inherit;
}

.chat-dialog input[type="checkbox"] {
  width: 14px;
  height: 14px;
  margin: 0;
  padding: 0;
  border: 0;
  border-radius: 3px;
  background: transparent;
  accent-color: var(--st-accent);
  flex: 0 0 auto;
}

.chat-model-pick {
  border: 0;
  margin: 0;
  padding: 0;
  min-width: 0;
  display: grid;
  gap: 4px;
}

.chat-model-pick legend {
  padding: 0;
  font-size: 12px;
  color: var(--st-muted);
}

.chat-dialog-actions {
  display: flex;
  justify-content: flex-end;
  gap: 8px;
}

.chat-compare-list {
  display: grid;
  gap: 6px;
  max-height: 240px;
  overflow: auto;
}

.chat-compare-list label {
  display: flex;
  align-items: center;
  gap: 8px;
  min-width: 0;
  color: var(--st-text);
  font-size: 13px;
  padding: 4px 2px;
  border-radius: 6px;
}

.chat-compare-list label:hover {
  background: var(--st-accent-soft);
}

.chat-compare-list label:has(input:disabled) {
  opacity: 0.55;
}

.chat-compare-list label:has(input:disabled):hover {
  background: transparent;
}

.chat-compare-list label span {
  min-width: 0;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.chat-compare-result-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
  padding: 12px 16px;
  border-bottom: 1px solid var(--st-border);
}

.chat-compare-result-body {
  display: grid;
  gap: 12px;
  padding: 16px;
  max-height: 70vh;
  overflow: auto;
}

.chat-compare-card {
  border: 1px solid var(--st-border);
  border-radius: 8px;
  padding: 10px 12px;
  background: var(--st-bg);
}

.chat-compare-card h4 {
  margin: 0 0 6px;
  font-size: 13px;
}

.chat-compare-card pre {
  margin: 0 0 8px;
  white-space: pre-wrap;
  word-break: break-word;
  font: inherit;
  font-size: 13px;
}

@media (max-width: 1100px) {
  .chat-shell {
    --rail-left: minmax(180px, 220px);
    --rail-right: minmax(220px, 280px);
  }
}

@media (max-width: 860px) {
  .chat-shell {
    grid-template-columns: 1fr;
    grid-template-rows: auto minmax(0, 1fr) auto;
    overflow: auto;
  }

  .chat-rail,
  .chat-main,
  .chat-context {
    grid-column: auto;
  }

  /* 单列时按可见的块重排行高 */
  .chat-shell.is-left-hidden {
    grid-template-rows: minmax(0, 1fr) auto;
  }

  .chat-shell.is-right-hidden {
    grid-template-rows: auto minmax(0, 1fr);
  }

  .chat-shell.is-left-hidden.is-right-hidden {
    grid-template-rows: minmax(0, 1fr);
  }

  .chat-rail {
    border-right: 0;
    border-bottom: 1px solid var(--st-border);
    max-height: 28vh;
  }

  .chat-context {
    border-left: 0;
    border-top: 1px solid var(--st-border);
    max-height: 36vh;
  }

  .chat-main {
    min-height: 42vh;
  }

  .chat-reply-track {
    --card-peek: 48px;
  }

  .chat-reply-track:not([data-count="1"]) .chat-reply-card {
    flex-basis: calc(100% - var(--card-peek));
    width: calc(100% - var(--card-peek));
  }
}