:root {
  --stage5-chat-reading-width: 820px;
  --stage5-chat-composer-width: 900px;
}

body.tq-surface-chat {
  --chat-message-foreground: #0d0d0d;
  --chat-message-font-weight: 400;
  --chat-user-bubble-background: color-mix(in srgb, var(--color-bg-surface) 97%, #0d0d0d);
  --chat-user-bubble-shadow:
    0 1px 2px rgba(13, 13, 13, 0.05),
    0 6px 16px rgba(17, 28, 48, 0.055);
}

body.tq-surface-chat,
body.tq-surface-chat .tq-chat-app,
body.tq-surface-chat .chat-main {
  background: var(--color-bg-surface);
  color: var(--color-text-primary);
  font-family: var(--font-sans);
  font-synthesis: none;
}

body.tq-surface-chat .chat-main {
  grid-template-rows: 64px minmax(0, 1fr);
}

body.tq-surface-chat .chat-header {
  z-index: 14;
  min-height: 64px;
  padding: 10px clamp(18px, 4vw, 40px);
  border-bottom: 0;
  background: color-mix(in srgb, var(--color-bg-surface) 94%, transparent);
  box-shadow: none;
}

body.tq-surface-chat .header-title {
  display: none;
}

body.tq-surface-chat .flash-model-picker {
  z-index: 25;
  margin-left: auto;
}

body.tq-surface-chat .flash-model-button {
  min-height: 40px;
  padding: 4px 10px;
  border-color: var(--color-border-default);
  background: var(--color-bg-surface);
  box-shadow: var(--shadow-xs);
}

body.tq-surface-chat .flash-model-button strong,
body.tq-surface-chat .flash-model-menu-react strong {
  font-weight: 600;
}

body.tq-surface-chat .flash-model-menu-react {
  align-content: start;
  max-height: min(680px, calc(var(--chat-viewport-height) - 88px - env(safe-area-inset-bottom)));
  overflow-x: hidden;
  overflow-y: auto;
  overscroll-behavior: contain;
  -webkit-overflow-scrolling: touch;
  scrollbar-gutter: stable;
  touch-action: pan-y;
}

.stage5-mode-switch {
  position: absolute;
  top: 11px;
  left: 50%;
  z-index: 24;
  display: grid;
  grid-template-columns: repeat(2, minmax(82px, 1fr));
  gap: 2px;
  padding: 3px;
  border: 1px solid var(--color-border-muted);
  border-radius: 999px;
  background: var(--color-bg-muted);
  transform: translateX(-50%);
}

.stage5-mode-switch a {
  display: grid;
  min-height: 34px;
  padding: 0 16px;
  border-radius: 999px;
  color: var(--color-text-muted);
  font-size: 14px;
  font-weight: 500;
  line-height: 34px;
  text-align: center;
  transition: color 160ms ease, background 160ms ease, box-shadow 160ms ease;
}

.stage5-mode-switch a:hover {
  color: var(--color-text-primary);
}

.stage5-mode-switch a.active {
  color: var(--color-text-primary);
  background: var(--color-bg-surface);
  box-shadow: var(--shadow-xs);
}

body.tq-surface-chat .assistant-thread {
  min-height: 0;
}

body.tq-surface-chat .chat-scroll {
  padding: 30px clamp(22px, 5vw, 64px) 24px;
}

body.tq-surface-chat .message-column {
  width: min(100%, var(--stage5-chat-reading-width));
  gap: 0;
}

body.tq-surface-chat .message + .message {
  margin-top: 28px;
}

body.tq-surface-chat .message.assistant + .message.user {
  margin-top: 44px;
}

body.tq-surface-chat .message.assistant .message-bubble {
  width: 100%;
  padding: 0;
}

body.tq-surface-chat .message.user .message-bubble {
  max-width: min(76%, 680px);
  padding: 10px 16px;
  border: 0;
  border-radius: 24px;
  background: var(--chat-user-bubble-background);
  box-shadow: var(--chat-user-bubble-shadow);
}

body.tq-surface-chat .message-meta {
  display: none;
}

body.tq-surface-chat .markdown-body,
body.tq-surface-chat .message.assistant .markdown-body {
  color: var(--chat-message-foreground);
  font-size: 16px;
  font-weight: var(--chat-message-font-weight);
  line-height: 1.6;
}

body.tq-surface-chat .message.user .markdown-body {
  color: var(--chat-message-foreground);
  font-size: 16px;
  font-weight: var(--chat-message-font-weight);
  line-height: 1.5;
}

body.tq-surface-chat .markdown-body p {
  color: inherit;
  line-height: inherit;
  margin: 0 0 10px;
}

body.tq-surface-chat .markdown-body p:last-child {
  margin-bottom: 0;
}

body.tq-surface-chat .message.user .markdown-body p {
  margin: 0;
}

body.tq-surface-chat .message.user .markdown-body p + p {
  margin-top: 8px;
}

body.tq-surface-chat .markdown-body h1,
body.tq-surface-chat .markdown-body h2,
body.tq-surface-chat .markdown-body h3,
body.tq-surface-chat .markdown-body h4 {
  color: var(--color-text-primary);
  font-weight: 600;
}

body.tq-surface-chat .message-actions {
  gap: 4px;
  margin-top: 6px;
}

body.tq-surface-chat .message-actions > span {
  display: inline-flex;
  color: var(--color-text-secondary);
  background: transparent;
  padding-left: 0;
}

body.tq-surface-chat .message-actions button {
  width: 30px;
  height: 30px;
  color: var(--color-text-muted);
}

body.tq-surface-chat .message-actions button:hover,
body.tq-surface-chat .message-actions button.active {
  color: var(--color-text-primary);
  background: var(--color-bg-muted);
}

body.tq-surface-chat .thinking-line {
  padding: 8px 12px;
  color: var(--color-text-secondary);
  background: var(--color-bg-muted);
  font-size: 14px;
  font-weight: 400;
}

body.tq-surface-chat .composer-shell {
  padding: 10px clamp(22px, 5vw, 64px) max(16px, env(safe-area-inset-bottom));
  background: var(--color-bg-surface);
}

body.tq-surface-chat .composer-shell > * {
  width: min(100%, var(--stage5-chat-composer-width));
}

body.tq-surface-chat .prompt-input {
  grid-template-columns: 42px minmax(0, 1fr) auto 52px;
  gap: 6px;
  min-height: 68px;
  padding: 7px;
  border: 1px solid var(--color-border-default);
  border-radius: 26px;
  background: var(--color-bg-surface);
  box-shadow: none;
}

body.tq-surface-chat.stage5-chat-pro .prompt-input {
  grid-template-columns: 42px minmax(0, 1fr) 52px;
}

body.tq-surface-chat .prompt-input:focus-within {
  border-color: var(--component-control-border-focus);
  box-shadow: none;
}

body.tq-surface-chat .prompt-plus {
  width: 42px;
  height: 52px;
  color: var(--color-text-secondary);
  box-shadow: none !important;
}

body.tq-surface-chat .prompt-plus:hover,
body.tq-surface-chat .prompt-plus.open {
  color: var(--color-text-primary);
  background: transparent;
  box-shadow: none !important;
  transform: none;
}

body.tq-surface-chat .prompt-plus:focus-visible {
  outline: 2px solid var(--component-control-border-focus);
  outline-offset: -3px;
}

body.tq-surface-chat .prompt-textarea {
  min-height: 42px;
  padding: 10px 4px;
  color: var(--color-text-primary);
  font-size: 16px;
  font-weight: 400;
  line-height: 22px;
}

body.tq-surface-chat .prompt-textarea::placeholder {
  color: var(--color-placeholder);
}

body.tq-surface-chat .send-button {
  width: 52px;
  height: 52px;
  color: var(--color-brand-foreground);
  background: var(--color-brand);
  box-shadow: none;
}

body.tq-surface-chat .send-button:disabled {
  color: var(--color-text-muted);
  background: var(--color-bg-muted);
  cursor: not-allowed;
}

body.tq-surface-chat .send-button.stopping {
  color: var(--color-text-inverse);
  background: var(--color-text-primary);
}

.stage5-effort-control {
  position: relative;
  align-self: center;
}

.stage5-effort-control[hidden] {
  display: none;
}

.stage5-effort-button {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  min-height: 38px;
  padding: 0 11px;
  border: 0;
  border-radius: 999px;
  color: var(--color-text-secondary);
  background: var(--color-bg-muted);
  font-size: 12px;
  font-weight: 500;
  white-space: nowrap;
}

.stage5-effort-button:hover,
.stage5-effort-button[aria-expanded="true"] {
  color: var(--color-brand);
  background: var(--color-accent);
}

.stage5-effort-button strong {
  font-weight: 600;
}

.stage5-effort-prefix::after {
  content: " ·";
}

.stage5-effort-menu {
  position: absolute;
  right: 0;
  bottom: calc(100% + 12px);
  z-index: 60;
  display: grid;
  gap: 3px;
  width: 250px;
  max-height: min(430px, 60vh);
  padding: 8px;
  overflow: auto;
  border: 1px solid var(--color-border-default);
  border-radius: 18px;
  background: var(--color-bg-surface);
  box-shadow: var(--shadow-md);
}

.stage5-effort-menu[hidden] {
  display: none;
}

.stage5-effort-option {
  display: flex;
  align-items: center;
  width: 100%;
  min-height: 44px;
  padding: 8px 10px;
  border: 0;
  border-radius: 12px;
  color: var(--color-text-primary);
  background: transparent;
  text-align: left;
}

.stage5-effort-option:hover,
.stage5-effort-option.active {
  background: var(--color-accent);
}

.stage5-effort-option span {
  font-size: 14px;
  font-weight: 600;
}

.stage5-empty-copy {
  color: var(--color-text-primary);
  font-size: clamp(24px, 2.4vw, 32px);
  font-weight: 500;
  line-height: 1.25;
  text-align: center;
}

.stage5-empty-copy[hidden] {
  display: none;
}

body.tq-surface-chat .tool-panel-react,
body.tq-surface-chat .flash-model-menu-react {
  border-color: var(--color-border-default);
  background: var(--color-bg-surface);
  box-shadow: var(--shadow-md);
}

body.tq-surface-chat .tool-panel-react strong,
body.tq-surface-chat .history-open span,
body.tq-surface-chat .new-chat-button,
body.tq-surface-chat .sidebar-brand strong {
  font-weight: 600;
}

body.tq-surface-chat .feedback-submit,
body.tq-surface-chat .feedback-question {
  font-weight: 600;
}

@media (min-width: 900px) {
  body.tq-surface-chat .stage5-chat-empty .assistant-thread {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 28px;
    padding: 0 clamp(30px, 7vw, 92px) 25vh;
    overflow: visible;
  }

  body.tq-surface-chat .stage5-chat-empty .chat-scroll {
    display: none;
  }

  body.tq-surface-chat .stage5-chat-empty .composer-shell {
    width: min(100%, calc(var(--stage5-chat-composer-width) + 128px));
    padding: 0;
    background: transparent;
  }
}

@media (max-width: 899px) {
  body.tq-surface-chat .chat-main {
    grid-template-rows: 64px minmax(0, 1fr);
    width: 100%;
    border: 0;
  }

  body.tq-surface-chat .chat-header {
    min-height: 64px;
    padding: 10px 12px 10px 60px;
  }

  body.tq-surface-chat .flash-model-button {
    max-width: 104px;
    min-height: 38px;
    padding: 3px 8px;
  }

  body.tq-surface-chat .flash-model-button strong {
    font-size: 11px;
  }

  .stage5-mode-switch {
    top: 11px;
    grid-template-columns: repeat(2, minmax(58px, 1fr));
  }

  .stage5-mode-switch a {
    min-height: 34px;
    padding: 0 10px;
    font-size: 13px;
    line-height: 34px;
  }

  body.tq-surface-chat .chat-scroll {
    padding: 18px 18px 8px;
  }

  body.tq-surface-chat .message-column {
    gap: 0;
  }

  body.tq-surface-chat .message.user .message-bubble {
    max-width: 84%;
  }

  body.tq-surface-chat .markdown-body,
  body.tq-surface-chat .message.assistant .markdown-body {
    font-size: 16px;
    line-height: 1.6;
  }

  body.tq-surface-chat .composer-shell {
    padding: 8px 12px max(10px, env(safe-area-inset-bottom));
  }

  body.tq-surface-chat .prompt-input {
    grid-template-columns: 38px minmax(0, 1fr) auto 48px;
    min-height: 64px;
    border-radius: 24px;
  }

  body.tq-surface-chat.stage5-chat-pro .prompt-input {
    grid-template-columns: 38px minmax(0, 1fr) 48px;
  }

  body.tq-surface-chat .prompt-plus {
    width: 38px;
    height: 48px;
  }

  body.tq-surface-chat .send-button {
    width: 48px;
    height: 48px;
  }

  .stage5-effort-prefix {
    display: none;
  }

  .stage5-effort-button {
    min-height: 34px;
    padding: 0 9px;
  }

  .stage5-effort-menu {
    right: -54px;
    width: min(250px, calc(100vw - 24px));
  }

  .stage5-empty-copy {
    display: none;
  }
}

@media (max-width: 390px) {
  body.tq-surface-chat .flash-model-button {
    max-width: 86px;
  }

  body.tq-surface-chat .flash-model-button span,
  body.tq-surface-chat .flash-model-button img {
    width: 20px;
    height: 20px;
  }

  .stage5-mode-switch {
    left: calc(50% - 4px);
  }

  body.tq-surface-chat .prompt-input {
    grid-template-columns: 36px minmax(0, 1fr) auto 46px;
    gap: 4px;
  }

  body.tq-surface-chat.stage5-chat-pro .prompt-input {
    grid-template-columns: 36px minmax(0, 1fr) 46px;
  }

  body.tq-surface-chat .prompt-plus {
    width: 36px;
  }

  body.tq-surface-chat .send-button {
    width: 46px;
    height: 46px;
  }
}