/* ============================================================
   ChatGPT Export Viewer — Brooks Solutions theme
   Dark-only, gold accent, DM Sans + Instrument Serif.
   Same DOM as the original viewer; only the visual chrome changes.
   ============================================================ */

:root {
  /* Brooks Solutions design tokens */
  --bg-deep: #0a0a0c;
  --bg-surface: #141418;
  --bg-elevated: #1c1c22;
  --text-primary: #f0efe9;
  --text-secondary: #a0a0a5;
  --text-muted: #6a6a6f;
  --accent: #c9a55c;
  --accent-hover: #d4b370;
  --accent-dim: rgba(201, 165, 92, 0.15);
  --accent-faint: rgba(201, 165, 92, 0.08);
  --border: rgba(255, 255, 255, 0.06);
  --border-hover: rgba(255, 255, 255, 0.12);
  --border-strong: rgba(255, 255, 255, 0.18);

  /* Mapped from the original viewer tokens to the new palette */
  --bg: var(--bg-deep);
  --bg-elev: var(--bg-surface);
  --bg-sidebar: #0e0e11;
  --bg-hover: var(--bg-elevated);
  --bg-active: #25252c;
  --text: var(--text-primary);
  --focus-ring: var(--accent);

  --user-bg: var(--bg-elevated);
  --assistant-bg: transparent;
  --code-bg: #0e0e11;
  --code-border: var(--border);

  --tool-bg: rgba(201, 165, 92, 0.06);
  --tool-border: rgba(201, 165, 92, 0.22);
  --tool-text: var(--accent);

  --thinking-bg: rgba(120, 160, 220, 0.06);
  --thinking-border: rgba(120, 160, 220, 0.22);

  --search-hit-bg: rgba(201, 165, 92, 0.28);
  --search-hit-text: #fff1cf;
  --search-source-bg: rgba(201, 165, 92, 0.18);

  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.35);
  --shadow-md: 0 8px 24px rgba(0, 0, 0, 0.45);
  --shadow-lg: 0 24px 60px rgba(0, 0, 0, 0.55);

  --radius: 14px;
  --radius-sm: 10px;
  --radius-pill: 100px;

  --font-sans: 'DM Sans', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  --font-serif: 'Instrument Serif', Georgia, serif;
  --font-mono: "SF Mono", "Cascadia Mono", Menlo, Monaco, "Courier New", monospace;
}

/* ---- Reset / base ---- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html, body { height: 100%; }
[hidden] { display: none !important; }

body {
  font-family: var(--font-sans);
  font-size: 15px;
  line-height: 1.55;
  background: var(--bg-deep);
  color: var(--text-primary);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow: hidden;
}

/* Subtle ambient glow + grain to match the marketing site */
body::before {
  content: '';
  position: fixed;
  top: -25%;
  right: -15%;
  width: 70%;
  height: 80%;
  background: radial-gradient(ellipse, var(--accent-dim) 0%, transparent 65%);
  pointer-events: none;
  z-index: 0;
}
body::after {
  content: '';
  position: fixed;
  inset: 0;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 256 256' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='noise'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23noise)'/%3E%3C/svg%3E");
  opacity: 0.03;
  pointer-events: none;
  z-index: 1000;
}

#app {
  position: relative;
  z-index: 1;
  display: flex;
  flex-direction: column;
  height: 100vh;
  height: 100dvh;
}

a { color: var(--accent); text-decoration: none; transition: color 0.2s ease; }
a:hover { color: var(--accent-hover); text-decoration: underline; }

button { font-family: inherit; }

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
  border-radius: 4px;
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

/* ---- Topbar (glass header — matches site nav) ---- */
.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.85rem 1.5rem;
  background: rgba(10, 10, 12, 0.8);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border);
  flex-shrink: 0;
  z-index: 30;
}

.brand {
  display: flex;
  align-items: center;
  gap: 0.85rem;
  min-width: 0;
}
.brand-link { display: inline-flex; align-items: center; }
.brand-link:hover { text-decoration: none; }
.brand-logo {
  font-family: var(--font-serif);
  font-size: 1.2rem;
  font-weight: 400;
  letter-spacing: -0.02em;
  color: var(--text-primary);
  white-space: nowrap;
}
.brand-dot { color: var(--accent); }
.brand-divider {
  color: var(--text-muted);
  font-weight: 300;
  font-size: 1rem;
}
.brand-text {
  font-family: var(--font-sans);
  font-size: 0.85rem;
  font-weight: 500;
  letter-spacing: 0.02em;
  color: var(--text-secondary);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.sidebar-toggle {
  padding: 0.35rem 0.55rem;
  font-size: 1.1rem;
}

.topbar-right {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.privacy-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.4rem 0.85rem;
  border-radius: var(--radius-pill);
  background: var(--accent-dim);
  color: var(--accent);
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.02em;
  border: 1px solid rgba(201, 165, 92, 0.25);
  cursor: pointer;
  transition: all 0.2s ease;
}
.privacy-badge:hover {
  background: rgba(201, 165, 92, 0.22);
  border-color: rgba(201, 165, 92, 0.4);
}
.privacy-badge .lock { font-size: 0.7rem; }

/* ---- Buttons ---- */
.btn-primary, .btn-icon, .btn-text {
  font: inherit;
  cursor: pointer;
  border-radius: var(--radius-pill);
  border: 1px solid transparent;
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  transition: all 0.25s ease;
  font-weight: 500;
}

.btn-primary {
  background: var(--accent);
  color: var(--bg-deep);
  padding: 0.55rem 1.1rem;
  font-weight: 600;
  font-size: 0.82rem;
  border-color: var(--accent);
}
.btn-primary:hover:not(:disabled) {
  background: transparent;
  color: var(--accent);
}
.btn-primary:disabled {
  opacity: 0.4;
  cursor: not-allowed;
}

.btn-icon {
  background: var(--bg-surface);
  color: var(--text-secondary);
  padding: 0.45rem 0.85rem;
  border-color: var(--border);
  font-size: 0.8rem;
}
.btn-icon:hover {
  background: var(--bg-elevated);
  color: var(--text-primary);
  border-color: var(--border-hover);
}

.btn-text {
  background: transparent;
  color: var(--text-secondary);
  padding: 0.45rem 0.9rem;
  font-size: 0.8rem;
  border: 1px solid var(--border);
}
.btn-text:hover {
  background: var(--bg-surface);
  color: var(--text-primary);
  border-color: var(--border-hover);
}

.link-btn {
  background: none;
  border: 0;
  padding: 0;
  color: var(--accent);
  font: inherit;
  font-size: 0.72rem;
  font-weight: 500;
  cursor: pointer;
  letter-spacing: 0.02em;
}
.link-btn:hover { color: var(--accent-hover); text-decoration: underline; }

/* ---- Main layout ---- */
#main { flex: 1; min-height: 0; display: flex; }

/* ---- Dropzone (empty state) ---- */
.dropzone {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 3rem 1.5rem;
  position: relative;
}
.dropzone-inner {
  width: 100%;
  max-width: 640px;
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  position: relative;
  z-index: 1;
}

.dropzone-card {
  background: var(--bg-surface);
  border: 1px dashed var(--border-hover);
  border-radius: var(--radius);
  padding: 3rem 2rem;
  text-align: center;
  transition: all 0.3s ease;
}
.dropzone-card.dragging {
  border-color: var(--accent);
  border-style: solid;
  background: linear-gradient(135deg, var(--bg-surface), rgba(201, 165, 92, 0.06));
}
.big-icon {
  font-size: 3rem;
  line-height: 1;
  margin-bottom: 1rem;
  opacity: 0.85;
}
.dropzone-card h1 {
  margin: 0 0 0.5rem;
  font-family: var(--font-serif);
  font-size: 2rem;
  font-weight: 400;
  letter-spacing: -0.02em;
  line-height: 1.2;
}
.dropzone-card .sub {
  margin: 0 0 1.25rem;
  color: var(--text-secondary);
  font-size: 1rem;
}
.link {
  color: var(--accent);
  cursor: pointer;
  font-weight: 500;
}
.link:hover { color: var(--accent-hover); text-decoration: underline; }

.hint {
  font-size: 0.82rem;
  color: var(--text-muted);
  margin: 0;
}
.hint code {
  background: var(--code-bg);
  padding: 0.1rem 0.4rem;
  border-radius: 4px;
  font-size: 0.78rem;
  border: 1px solid var(--code-border);
  font-family: var(--font-mono);
  color: var(--text-secondary);
}
.hint a { color: var(--accent); }

/* Privacy card — matches the .feature-card / .tech-card pattern from the site */
.privacy-card {
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.25rem 1.5rem;
}
.privacy-card-header {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: 0.75rem;
}
.privacy-card-header h2 {
  margin: 0;
  font-family: var(--font-serif);
  font-size: 1.15rem;
  font-weight: 400;
  letter-spacing: -0.01em;
}
.lock-large {
  font-size: 1.25rem;
  width: 36px;
  height: 36px;
  background: var(--accent-dim);
  border: 1px solid rgba(201, 165, 92, 0.2);
  border-radius: 10px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
}
.privacy-card ul {
  margin: 0;
  padding-left: 1.1rem;
  font-size: 0.88rem;
  color: var(--text-secondary);
  line-height: 1.7;
}
.privacy-card li::marker { color: var(--accent); }
.privacy-card strong { color: var(--text-primary); font-weight: 600; }

/* ---- Viewer (loaded state) ---- */
.viewer { flex: 1; display: flex; min-height: 0; position: relative; z-index: 1; }

/* ---- Sidebar ---- */
.sidebar {
  width: 300px;
  flex-shrink: 0;
  display: flex;
  flex-direction: column;
  background: var(--bg-sidebar);
  border-right: 1px solid var(--border);
  min-height: 0;
}
.sidebar-search { padding: 0.75rem; border-bottom: 1px solid var(--border); }
.sidebar-search input {
  width: 100%;
  padding: 0.55rem 0.75rem;
  border: 1px solid var(--border);
  background: var(--bg-surface);
  color: var(--text-primary);
  border-radius: var(--radius-sm);
  font: inherit;
  font-size: 0.85rem;
  outline: none;
  transition: border-color 0.2s ease, background 0.2s ease;
}
.sidebar-search input::placeholder { color: var(--text-muted); }
.sidebar-search input:focus {
  border-color: var(--accent);
  background: var(--bg-elevated);
}

.conv-list { flex: 1; overflow-y: auto; padding: 0.4rem 0.5rem 0.75rem; outline: none; }
.conv-group-label {
  padding: 0.85rem 0.75rem 0.3rem;
  font-size: 0.68rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--accent);
}

.conv-item {
  display: block;
  width: 100%;
  text-align: left;
  background: transparent;
  border: 1px solid transparent;
  padding: 0.55rem 0.7rem;
  border-radius: var(--radius-sm);
  cursor: pointer;
  font: inherit;
  font-size: 0.86rem;
  color: var(--text-secondary);
  margin: 1px 0;
  transition: all 0.15s ease;
}
.conv-item:hover {
  background: var(--bg-surface);
  color: var(--text-primary);
}
.conv-item.active {
  background: var(--bg-elevated);
  color: var(--text-primary);
  font-weight: 500;
  border-color: var(--border);
}
.conv-item.search-result { padding: 0.6rem 0.7rem 0.65rem; }

.conv-title {
  display: block;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.conv-snippet {
  display: block;
  font-size: 0.72rem;
  color: var(--text-muted);
  margin-top: 2px;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  font-weight: 400;
}
.conv-search-snippet {
  display: -webkit-box;
  margin-top: 4px;
  overflow: hidden;
  color: var(--text-secondary);
  font-size: 0.78rem;
  line-height: 1.4;
  font-weight: 400;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
}
.conv-search-meta {
  display: block;
  margin-top: 5px;
  color: var(--text-muted);
  font-size: 0.72rem;
  font-weight: 400;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.conv-match-source {
  display: inline-flex;
  align-items: center;
  max-width: 86px;
  margin-right: 4px;
  overflow: hidden;
  padding: 1px 6px;
  border-radius: 4px;
  background: var(--search-source-bg);
  color: var(--accent);
  font-size: 0.65rem;
  font-weight: 700;
  line-height: 1.3;
  text-overflow: ellipsis;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  vertical-align: 1px;
  white-space: nowrap;
}
.search-hit {
  border-radius: 3px;
  padding: 0 2px;
  background: var(--search-hit-bg);
  color: var(--search-hit-text);
  font-weight: 700;
}
.empty-search-state {
  padding: 2.25rem 1rem;
  color: var(--text-muted);
  font-size: 0.82rem;
  text-align: center;
}
.empty-search-state strong {
  display: block;
  margin-bottom: 5px;
  color: var(--text-secondary);
  font-size: 0.85rem;
  font-weight: 600;
}
.empty-search-state span { display: block; }

.sidebar-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
  padding: 0.75rem 1rem;
  border-top: 1px solid var(--border);
  font-size: 0.72rem;
  color: var(--text-muted);
  background: rgba(10, 10, 12, 0.5);
}

/* ---- Chat pane ---- */
.chat-pane {
  flex: 1;
  display: flex;
  flex-direction: column;
  min-width: 0;
  background: var(--bg-deep);
}
.chat-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 1rem;
  padding: 1rem 1.5rem;
  border-bottom: 1px solid var(--border);
  background: rgba(20, 20, 24, 0.5);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  flex-shrink: 0;
}
.chat-title-wrap { min-width: 0; flex: 1; }
.chat-title-wrap h2 {
  margin: 0;
  font-family: var(--font-serif);
  font-size: 1.35rem;
  font-weight: 400;
  letter-spacing: -0.01em;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  color: var(--text-primary);
}
.chat-meta {
  font-size: 0.78rem;
  color: var(--text-muted);
  margin-top: 4px;
}
.chat-actions { display: flex; gap: 0.5rem; flex-shrink: 0; }

.filters-panel {
  display: flex;
  flex-wrap: wrap;
  gap: 1.25rem;
  padding: 0.7rem 1.5rem;
  background: var(--bg-surface);
  border-bottom: 1px solid var(--border);
  font-size: 0.82rem;
  color: var(--text-secondary);
}
.filters-panel label {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  cursor: pointer;
}
.filters-panel input[type="checkbox"] {
  margin: 0;
  cursor: pointer;
  accent-color: var(--accent);
}

.messages-container {
  flex: 1;
  overflow-y: auto;
  padding: 1.5rem 0 4rem;
  outline: none;
}
.empty-chat-hint {
  text-align: center;
  color: var(--text-muted);
  padding: 4rem 1.5rem;
  font-size: 0.9rem;
  font-style: italic;
}

/* ---- Messages ---- */
.message-row {
  max-width: 760px;
  margin: 0 auto;
  padding: 1rem 1.5rem;
  position: relative;
}
.message-row.role-user .message-bubble {
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: 18px;
  padding: 0.8rem 1.1rem;
  margin-left: auto;
  max-width: 85%;
  width: fit-content;
}
.message-row.role-user { display: flex; flex-direction: column; align-items: flex-end; }

.message-row.role-assistant .message-bubble {
  background: var(--assistant-bg);
  padding: 0.25rem 0;
}

.message-row.role-tool .message-bubble,
.message-row.role-system .message-bubble {
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 0.7rem 1rem;
  font-size: 0.85rem;
  color: var(--text-secondary);
}

.message-meta {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.7rem;
  color: var(--accent);
  margin-bottom: 0.5rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.12em;
}
.role-user .message-meta { justify-content: flex-end; }
.role-tool .message-meta { color: var(--accent); }

.alternates-badge {
  display: inline-block;
  font-size: 0.65rem;
  padding: 1px 7px;
  border-radius: var(--radius-pill);
  background: var(--bg-elevated);
  color: var(--text-secondary);
  border: 1px solid var(--border);
  text-transform: none;
  letter-spacing: 0;
  font-weight: 500;
}

.message-actions {
  display: flex;
  margin-top: 2px;
}
.role-user .message-actions {
  justify-content: flex-end;
  width: 85%;
}

.message-row .copy-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  margin: 0;
  padding: 0;
  background: transparent;
  border: 0;
  border-radius: var(--radius-sm);
  color: var(--text-muted);
  cursor: pointer;
  opacity: 0.45;
  transition: opacity 0.15s ease, background 0.15s ease, color 0.15s ease;
}
.message-row .copy-btn-inline {
  width: 22px;
  height: 22px;
}
.copy-btn-inline .copy-btn-icon { width: 14px; height: 14px; }
.copy-btn-inline .copy-btn-icon-copy::before,
.copy-btn-inline .copy-btn-icon-copy::after {
  width: 9px;
  height: 11px;
  border-width: 1.5px;
}
.copy-btn-inline .copy-btn-icon-copy::before { top: 1px; left: 4px; }
.copy-btn-inline .copy-btn-icon-copy::after  { top: 4px; left: 1px; }
.copy-btn-inline .copy-btn-icon-copied::before {
  top: 1px; left: 5px; width: 6px; height: 11px; border-width: 0 1.7px 1.7px 0;
}
.message-row .copy-btn-below {
  width: 30px;
  height: 30px;
}
.message-row:hover .copy-btn,
.message-row:focus-within .copy-btn,
.message-row .copy-btn:focus-visible { opacity: 1; color: var(--text-secondary); }
.message-row .copy-btn:hover {
  background: var(--bg-surface);
  color: var(--accent);
}
.message-row .copy-btn.copied {
  background: var(--accent-dim);
  color: var(--accent);
  opacity: 1;
}
.copy-btn-icon {
  position: relative;
  display: block;
  width: 18px;
  height: 18px;
}
.copy-btn-icon-copy::before,
.copy-btn-icon-copy::after {
  content: "";
  position: absolute;
  width: 11px;
  height: 13px;
  border: 1.7px solid currentColor;
  border-radius: 3px;
}
.copy-btn-icon-copy::before {
  top: 2px;
  left: 5px;
  background: var(--bg-deep);
}
.copy-btn-icon-copy::after {
  top: 5px;
  left: 2px;
  background: var(--bg-deep);
}
.copy-btn:hover .copy-btn-icon-copy::before,
.copy-btn:hover .copy-btn-icon-copy::after {
  background: var(--bg-surface);
}
.copy-btn.copied .copy-btn-icon-copy { display: none; }
.copy-btn-icon-copied { display: none; }
.copy-btn.copied .copy-btn-icon-copied { display: block; }
.copy-btn-icon-copied::before {
  content: "";
  position: absolute;
  top: 2px;
  left: 6px;
  width: 7px;
  height: 13px;
  border: solid currentColor;
  border-width: 0 2px 2px 0;
  transform: rotate(45deg);
}

@media (hover: none) {
  .message-row .copy-btn { opacity: 0.85; }
}

/* ---- Markdown content ---- */
.markdown {
  font-size: 0.95rem;
  line-height: 1.7;
  word-wrap: break-word;
  overflow-wrap: anywhere;
  color: var(--text-primary);
}
.markdown > *:first-child { margin-top: 0; }
.markdown > *:last-child { margin-bottom: 0; }
.markdown p { margin: 0.6em 0; }
.markdown h1, .markdown h2, .markdown h3, .markdown h4 {
  margin: 1.2em 0 0.5em;
  line-height: 1.3;
  font-family: var(--font-serif);
  font-weight: 400;
  letter-spacing: -0.01em;
}
.markdown h1 { font-size: 1.6em; }
.markdown h2 { font-size: 1.35em; }
.markdown h3 { font-size: 1.15em; }
.markdown h4 { font-size: 1em; font-family: var(--font-sans); font-weight: 600; }
.markdown ul, .markdown ol { margin: 0.5em 0; padding-left: 1.5em; }
.markdown li { margin: 0.2em 0; }
.markdown li > p { margin: 0.2em 0; }
.markdown li::marker { color: var(--accent); }
.markdown code {
  background: var(--code-bg);
  border: 1px solid var(--code-border);
  padding: 1px 6px;
  border-radius: 4px;
  font-family: var(--font-mono);
  font-size: 0.85em;
  word-break: break-word;
  color: var(--accent);
}
.markdown pre {
  background: var(--code-bg);
  border: 1px solid var(--code-border);
  padding: 0.85rem 1rem;
  border-radius: var(--radius-sm);
  overflow-x: auto;
  font-size: 0.82rem;
  line-height: 1.55;
  margin: 0.7em 0;
}
.markdown pre code {
  background: transparent;
  border: 0;
  padding: 0;
  font-size: inherit;
  word-break: normal;
  color: var(--text-primary);
}
.markdown blockquote {
  margin: 0.7em 0;
  padding: 0.25rem 1rem;
  border-left: 3px solid var(--accent);
  color: var(--text-secondary);
  background: rgba(201, 165, 92, 0.04);
  border-radius: 0 4px 4px 0;
}
.markdown table {
  border-collapse: collapse;
  margin: 0.7em 0;
  font-size: 0.92em;
  display: block;
  overflow-x: auto;
  max-width: 100%;
}
.markdown th, .markdown td {
  border: 1px solid var(--border);
  padding: 0.4rem 0.7rem;
  text-align: left;
}
.markdown th {
  background: var(--bg-surface);
  font-weight: 600;
  color: var(--text-primary);
}
.markdown a {
  color: var(--accent);
  text-decoration: underline;
  text-decoration-color: rgba(201, 165, 92, 0.4);
  text-underline-offset: 2px;
}
.markdown a:hover { color: var(--accent-hover); text-decoration-color: var(--accent-hover); }
.markdown hr { border: 0; border-top: 1px solid var(--border); margin: 1.2em 0; }
.markdown img { max-width: 100%; border-radius: var(--radius-sm); }

/* ---- Special blocks ---- */
.thinking-block, .tool-call, .tool-result, .recap, .muted-block {
  border-radius: var(--radius-sm);
  margin: 6px 0;
  font-size: 0.85rem;
}
.thinking-block {
  background: var(--thinking-bg);
  border: 1px solid var(--thinking-border);
  padding: 0.7rem 1rem;
}
.thinking-label, .tool-label {
  font-size: 0.7rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--text-secondary);
  margin-bottom: 6px;
}
.thinking-block details { margin: 4px 0; }
.thinking-block summary {
  cursor: pointer;
  font-weight: 500;
  padding: 3px 0;
  color: var(--text-primary);
}
.thinking-block summary:hover { color: var(--accent); }
.thinking-block details[open] summary { margin-bottom: 6px; }

.tool-call, .tool-result {
  background: var(--tool-bg);
  border: 1px solid var(--tool-border);
  padding: 0.7rem 1rem;
}
.tool-call .tool-label, .tool-result .tool-label { color: var(--accent); }
.tool-call pre, .tool-result pre {
  background: rgba(0, 0, 0, 0.35);
  border: 0;
  padding: 0.55rem 0.7rem;
  border-radius: 6px;
  font-size: 0.78rem;
  margin: 0;
  max-height: 280px;
  overflow: auto;
  color: var(--text-primary);
}

.recap {
  font-size: 0.78rem;
  color: var(--text-muted);
  font-style: italic;
  padding: 0.4rem 0.7rem;
  background: var(--bg-surface);
  border: 1px dashed var(--border);
}
.muted-block {
  font-size: 0.78rem;
  color: var(--text-muted);
  padding: 0.55rem 0.85rem;
  background: var(--bg-surface);
  border: 1px dashed var(--border);
}

.img-placeholder, .img-resolved {
  background: var(--bg-surface);
  border: 1px dashed var(--border-strong);
  padding: 0.85rem;
  border-radius: var(--radius-sm);
  text-align: center;
  font-size: 0.82rem;
  color: var(--text-muted);
  margin: 6px 0;
}
.img-resolved {
  border-style: solid;
  border-color: var(--border);
  padding: 0.4rem;
}
.img-resolved img {
  max-width: 100%;
  max-height: 480px;
  border-radius: 6px;
  display: block;
  margin: 0 auto;
}
.img-resolved figcaption {
  margin-top: 6px;
  font-size: 0.72rem;
  color: var(--text-muted);
}
.img-placeholder code {
  display: inline-block;
  margin-top: 6px;
  font-size: 0.7rem;
  background: var(--code-bg);
  padding: 2px 7px;
  border-radius: 4px;
  border: 1px solid var(--code-border);
  word-break: break-all;
  font-family: var(--font-mono);
}

/* ---- Toast ---- */
.toast {
  position: fixed;
  bottom: 1.5rem;
  left: 50%;
  transform: translateX(-50%);
  background: var(--text-primary);
  color: var(--bg-deep);
  padding: 0.65rem 1.25rem;
  border-radius: var(--radius-pill);
  font-size: 0.82rem;
  font-weight: 600;
  box-shadow: var(--shadow-md);
  z-index: 100;
  animation: toastIn 200ms ease;
  max-width: calc(100vw - 40px);
}
@keyframes toastIn {
  from { opacity: 0; transform: translate(-50%, 8px); }
  to   { opacity: 1; transform: translate(-50%, 0); }
}

/* ---- Sidebar backdrop (mobile slide-over) ---- */
.sidebar-backdrop {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.55);
  z-index: 19;
  opacity: 0;
  pointer-events: none;
  transition: opacity 150ms ease;
}
.sidebar-backdrop.show { opacity: 1; pointer-events: auto; }

/* ---- Scrollbars ---- */
*::-webkit-scrollbar { width: 10px; height: 10px; }
*::-webkit-scrollbar-track { background: transparent; }
*::-webkit-scrollbar-thumb {
  background: var(--border-strong);
  border-radius: 10px;
  border: 2px solid var(--bg-deep);
}
*::-webkit-scrollbar-thumb:hover { background: var(--text-muted); }

/* ---- Responsive ---- */
@media (max-width: 720px) {
  .topbar { padding: 0.65rem 1rem; }
  .brand { gap: 0.5rem; }
  .brand-divider, .brand-text { display: none; }
  .chat-actions .label { display: none; }
  .chat-header { padding: 0.85rem 1rem; }
  .message-row { padding: 1rem 1rem; }

  .dropzone { padding: 2rem 1rem; }
  .dropzone-card { padding: 2rem 1.25rem; }
  .dropzone-card h1 { font-size: 1.6rem; }

  .sidebar {
    position: absolute;
    top: 0;
    bottom: 0;
    left: 0;
    width: min(86vw, 320px);
    z-index: 20;
    transform: translateX(-100%);
    transition: transform 200ms ease;
    box-shadow: var(--shadow-lg);
  }
  .sidebar.open { transform: translateX(0); }
}

@media (min-width: 721px) {
  .sidebar.collapsed { display: none; }
  .sidebar-backdrop { display: none; }
}