/* Markdown Editor: dark theme, mobile first up to the phone breakpoint.
   Phones (< 768px) show one pane with Edit / Preview tabs; below 1024px the
   sidebar becomes a drawer; wider screens show the sidebar as a column. */

:root {
  color-scheme: dark;
  --bg: #0f172a;
  --surface: #1e293b;
  --surface-2: #273548;
  --line: #334155;
  --line-soft: rgb(148 163 184 / 0.14);
  --text: #e2e8f0;
  --strong: #f8fafc;
  --muted: #94a3b8;
  --faint: #7d8ba1;
  --accent: #60a5fa;
  --accent-strong: #93c5fd;
  --accent-soft: rgb(96 165 250 / 0.14);
  --accent-ink: #0b1220;
  --danger: #f87171;
  --danger-strong: #fca5a5;
  --ok: #4ade80;
  --warn: #fbbf24;
  --code-bg: #0f172a;
  --radius: 12px;
  --radius-sm: 10px;
  --shadow: 0 1px 2px rgb(2 6 23 / 0.35), 0 10px 30px rgb(2 6 23 / 0.28);
  --shadow-lg: 0 24px 64px rgb(2 6 23 / 0.6);
  --ease: cubic-bezier(0.2, 0, 0, 1);
  --fast: 150ms;
  --slow: 250ms;
  --font: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --mono: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, "Liberation Mono", monospace;
  --header-h: 56px;
  --footer-h: 42px;
  --side-w: 288px;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

[hidden] {
  display: none !important;
}

html {
  height: 100%;
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
}

body {
  height: 100%;
  margin: 0;
  overflow: hidden;
  background: var(--bg);
  color: var(--text);
  font: 15px/1.5 var(--font);
  -webkit-font-smoothing: antialiased;
}

button,
input,
textarea {
  font: inherit;
  color: inherit;
}

button {
  -webkit-tap-highlight-color: transparent;
}

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

::selection {
  background: rgb(96 165 250 / 0.32);
}

.visually-hidden,
.mirror-host {
  position: absolute !important;
  width: 1px !important;
  height: 1px !important;
  margin: -1px !important;
  padding: 0 !important;
  border: 0 !important;
  overflow: hidden !important;
  clip-path: inset(50%) !important;
  white-space: nowrap !important;
}

/* The mirror copies the editor's text styles to measure where lines start. */
.mirror-host {
  top: 0;
  left: 0;
  visibility: hidden;
  pointer-events: none;
}

.mirror {
  position: absolute;
  top: 0;
  left: 0;
  box-sizing: content-box;
  margin: 0;
  border: 0;
}

.icon {
  width: 20px;
  height: 20px;
  flex: none;
  fill: none;
  stroke: currentColor;
  stroke-width: 1.8;
  stroke-linecap: round;
  stroke-linejoin: round;
}

/* ------------------------------------------------------------------------
   Frame */

.app {
  display: grid;
  grid-template-columns: var(--side-w) minmax(0, 1fr);
  grid-template-rows: var(--header-h) minmax(0, 1fr) var(--footer-h);
  grid-template-areas:
    "top top"
    "side main"
    "foot foot";
  height: 100vh;
  height: 100dvh;
}

.topbar {
  grid-area: top;
  display: flex;
  align-items: center;
  gap: 8px;
  min-width: 0;
  padding: 0 12px 0 16px;
  border-bottom: 1px solid var(--line-soft);
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  min-width: 0;
  margin: 0;
  padding-right: 14px;
  border-right: 1px solid var(--line-soft);
  color: var(--strong);
  font-size: 17px;
  font-weight: 650;
  letter-spacing: -0.01em;
  white-space: nowrap;
}

.brand-name {
  overflow: hidden;
  text-overflow: ellipsis;
}

.logo {
  width: 30px;
  height: 30px;
  flex: none;
}

.doc-title {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  min-width: 0;
  max-width: 34ch;
  min-height: 40px;
  padding: 0 10px;
  border: 0;
  border-radius: var(--radius-sm);
  background: transparent;
  color: var(--text);
  font-size: 15px;
  font-weight: 550;
  cursor: pointer;
  transition: background-color var(--fast) var(--ease), color var(--fast) var(--ease);
}

.doc-title:hover {
  background: var(--surface);
}

.doc-title .icon {
  order: 2;
  width: 16px;
  height: 16px;
  color: var(--muted);
  opacity: 0.7;
}

.doc-title-text {
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.save-status {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  flex: none;
  color: var(--muted);
  font-size: 13px;
  white-space: nowrap;
}

.save-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--ok);
  box-shadow: 0 0 0 3px rgb(74 222 128 / 0.16);
  transition: background-color var(--fast) var(--ease), box-shadow var(--fast) var(--ease);
}

.save-status[data-state="pending"] .save-dot {
  background: var(--warn);
  box-shadow: 0 0 0 3px rgb(251 191 36 / 0.16);
  animation: pulse 0.9s ease-in-out infinite alternate;
}

.save-status[data-state="error"] {
  color: var(--danger);
}

.save-status[data-state="error"] .save-dot {
  background: var(--danger);
  box-shadow: 0 0 0 3px rgb(248 113 113 / 0.18);
}

@keyframes pulse {
  to {
    opacity: 0.35;
  }
}

.spacer {
  flex: 1;
}

/* ------------------------------------------------------------------------
   Buttons */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  min-height: 40px;
  padding: 0 14px;
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  background: var(--surface);
  color: var(--text);
  font-size: 14px;
  font-weight: 550;
  line-height: 1.15;
  cursor: pointer;
  user-select: none;
  transition: background-color var(--fast) var(--ease), border-color var(--fast) var(--ease),
    color var(--fast) var(--ease), transform var(--fast) var(--ease);
}

.btn:hover {
  border-color: #475569;
  background: var(--surface-2);
}

.btn:active {
  transform: translateY(1px);
}

.btn .icon {
  width: 18px;
  height: 18px;
}

.btn-primary {
  border-color: var(--accent);
  background: var(--accent);
  color: var(--accent-ink);
}

.btn-primary:hover {
  border-color: var(--accent-strong);
  background: var(--accent-strong);
}

.btn-danger {
  border-color: var(--danger);
  background: var(--danger);
  color: #1f0b0b;
}

.btn-danger:hover {
  border-color: var(--danger-strong);
  background: var(--danger-strong);
}

.btn-block {
  width: 100%;
}

.icon-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  flex: none;
  width: 40px;
  height: 40px;
  padding: 0;
  border: 0;
  border-radius: var(--radius-sm);
  background: transparent;
  color: var(--muted);
  cursor: pointer;
  transition: background-color var(--fast) var(--ease), color var(--fast) var(--ease), opacity var(--fast) var(--ease);
}

.icon-btn:hover {
  background: var(--surface);
  color: var(--text);
}

.lang-btn {
  min-width: 48px;
  padding: 0 10px;
  font-weight: 700;
  letter-spacing: 0.06em;
}

.menu-btn,
.drawer-close {
  display: none;
}

/* ------------------------------------------------------------------------
   Sidebar */

.sidebar {
  grid-area: side;
  display: flex;
  flex-direction: column;
  gap: 12px;
  min-height: 0;
  padding: 12px;
  overflow-y: auto;
  overscroll-behavior: contain;
  border-right: 1px solid var(--line-soft);
  background: var(--bg);
}

.side-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 24px;
  padding-left: 4px;
}

.side-title {
  margin: 0;
  color: var(--muted);
  font-size: 12px;
  font-weight: 650;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.side-section {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding-top: 12px;
  border-top: 1px solid var(--line-soft);
}

.side-section .side-title {
  padding-left: 4px;
}

.doc-list {
  display: flex;
  flex-direction: column;
  flex-shrink: 0;
  gap: 2px;
  max-height: 40vh;
  margin: 0;
  padding: 0;
  overflow-y: auto;
  list-style: none;
}

.doc-item {
  display: flex;
  align-items: center;
  border-radius: var(--radius-sm);
  transition: background-color var(--fast) var(--ease);
}

.doc-item:hover {
  background: rgb(30 41 59 / 0.6);
}

.doc-item.active {
  background: var(--surface);
  box-shadow: inset 3px 0 0 var(--accent);
}

.doc-open {
  display: flex;
  flex: 1;
  flex-direction: column;
  align-items: flex-start;
  justify-content: center;
  gap: 1px;
  min-width: 0;
  min-height: 48px;
  padding: 5px 8px 5px 12px;
  border: 0;
  border-radius: var(--radius-sm);
  background: none;
  color: var(--text);
  text-align: left;
  cursor: pointer;
}

.doc-name {
  max-width: 100%;
  overflow: hidden;
  font-size: 14px;
  font-weight: 550;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.doc-name.untitled {
  color: var(--muted);
  font-style: italic;
}

.doc-date {
  color: var(--muted);
  font-size: 12px;
  font-variant-numeric: tabular-nums;
}

.doc-action .icon {
  width: 18px;
  height: 18px;
}

.doc-action.danger:hover {
  color: var(--danger);
}

@media (hover: hover) and (pointer: fine) {
  .doc-item:not(:hover, :focus-within, .active) .doc-action {
    opacity: 0;
  }
}

.file-actions {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 6px;
}

.file-btn {
  justify-content: flex-start;
  gap: 7px;
  padding: 4px 8px;
  font-size: 13px;
  text-align: left;
}

.toc-list {
  margin: 0;
  padding: 0;
  list-style: none;
}

.toc-link {
  display: block;
  padding: 6px 10px 6px calc(10px + var(--depth, 0) * 14px);
  overflow: hidden;
  border-radius: 8px;
  color: var(--muted);
  font-size: 13.5px;
  line-height: 1.35;
  text-decoration: none;
  text-overflow: ellipsis;
  white-space: nowrap;
  transition: background-color var(--fast) var(--ease), color var(--fast) var(--ease);
}

.toc-link:hover {
  background: rgb(30 41 59 / 0.6);
  color: var(--text);
}

.toc-link[aria-current] {
  background: var(--accent-soft);
  color: var(--accent);
}

.toc-empty {
  margin: 0;
  padding: 0 4px;
  color: var(--muted);
  font-size: 13px;
}

.backdrop {
  display: none;
}

/* ------------------------------------------------------------------------
   Editor and preview */

.workspace {
  grid-area: main;
  display: flex;
  flex-direction: column;
  gap: 10px;
  min-width: 0;
  min-height: 0;
  padding: 12px;
}

.view-tabs {
  display: none;
}

.panes {
  display: grid;
  flex: 1;
  grid-template-columns: minmax(0, calc(var(--split, 50%) - 6px)) 12px minmax(0, 1fr);
  min-height: 0;
}

.pane {
  display: flex;
  flex-direction: column;
  min-width: 0;
  min-height: 0;
  overflow: hidden;
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
  background: var(--surface);
  box-shadow: var(--shadow);
  transition: border-color var(--fast) var(--ease);
}

.editor-pane:focus-within {
  border-color: rgb(96 165 250 / 0.5);
}

.toolbar {
  display: flex;
  flex-wrap: wrap;
  gap: 2px;
  padding: 6px 8px;
  border-bottom: 1px solid var(--line-soft);
}

.tool {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  padding: 0;
  border: 0;
  border-radius: 8px;
  background: transparent;
  color: var(--muted);
  cursor: pointer;
  transition: background-color var(--fast) var(--ease), color var(--fast) var(--ease);
}

.tool:hover {
  background: var(--surface-2);
  color: var(--text);
}

.tool:active {
  background: var(--accent-soft);
  color: var(--accent);
}

.editor {
  flex: 1;
  width: 100%;
  min-height: 0;
  margin: 0;
  padding: 16px 20px 48px;
  border: 0;
  outline: none;
  resize: none;
  background: transparent;
  color: var(--text);
  font: 14px/1.65 var(--mono);
  tab-size: 2;
  caret-color: var(--accent);
}

.editor::placeholder {
  color: #64748b;
}

.splitter {
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 6px;
  outline: none;
  cursor: col-resize;
  touch-action: none;
}

.splitter-grip {
  width: 4px;
  height: 44px;
  border-radius: 2px;
  background: var(--line);
  transition: background-color var(--fast) var(--ease), height var(--fast) var(--ease);
}

.splitter:hover .splitter-grip,
.resizing .splitter-grip {
  height: 72px;
  background: var(--accent);
}

.splitter:focus-visible .splitter-grip {
  background: var(--accent);
  box-shadow: 0 0 0 3px rgb(96 165 250 / 0.35);
}

.resizing,
.resizing * {
  cursor: col-resize !important;
  user-select: none;
}

.pane-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  min-height: 53px;
  padding: 6px 16px;
  border-bottom: 1px solid var(--line-soft);
}

.pane-title {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  flex: none;
  color: var(--muted);
  font-size: 12px;
  font-weight: 650;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.pane-title .icon {
  width: 18px;
  height: 18px;
}

.stats {
  min-width: 0;
  overflow: hidden;
  color: var(--muted);
  font-size: 12.5px;
  font-variant-numeric: tabular-nums;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.preview {
  flex: 1;
  min-height: 0;
  padding: 18px 26px 48px;
  overflow-y: auto;
  outline: none;
}

.preview:focus-visible {
  box-shadow: inset 0 0 0 2px var(--accent);
}

.editor,
.preview,
.sidebar,
.doc-list {
  scrollbar-color: #3b4a61 transparent;
  scrollbar-width: thin;
}

/* ------------------------------------------------------------------------
   Rendered Markdown */

.markdown-body {
  color: var(--text);
  font-size: 15px;
  line-height: 1.7;
  overflow-wrap: break-word;
}

.markdown-body > :first-child {
  margin-top: 0;
}

.markdown-body > :last-child {
  margin-bottom: 0;
}

.markdown-body :is(h1, h2, h3, h4, h5, h6) {
  margin: 1.6em 0 0.6em;
  color: var(--strong);
  font-weight: 650;
  line-height: 1.25;
  scroll-margin-top: 12px;
}

.markdown-body h1 {
  padding-bottom: 0.3em;
  border-bottom: 1px solid var(--line);
  font-size: 1.85em;
  letter-spacing: -0.015em;
}

.markdown-body h2 {
  padding-bottom: 0.25em;
  border-bottom: 1px solid var(--line);
  font-size: 1.4em;
  letter-spacing: -0.01em;
}

.markdown-body h3 {
  font-size: 1.18em;
}

.markdown-body h4 {
  font-size: 1.04em;
}

.markdown-body h5 {
  font-size: 0.95em;
}

.markdown-body h6 {
  color: var(--muted);
  font-size: 0.9em;
}

.markdown-body :is(p, ul, ol, blockquote, pre, table) {
  margin: 0 0 1em;
}

.markdown-body a {
  color: var(--accent);
  text-decoration: underline;
  text-decoration-color: rgb(96 165 250 / 0.45);
  text-underline-offset: 2px;
  transition: text-decoration-color var(--fast) var(--ease);
}

.markdown-body a:hover {
  text-decoration-color: currentColor;
}

.markdown-body strong {
  color: var(--strong);
  font-weight: 650;
}

.markdown-body del {
  color: var(--muted);
}

.markdown-body :is(ul, ol) {
  padding-left: 1.6em;
}

.markdown-body li + li,
.markdown-body li > :is(ul, ol) {
  margin-top: 0.25em;
}

.markdown-body li > :is(ul, ol) {
  margin-bottom: 0;
}

.markdown-body li > p {
  margin-bottom: 0.5em;
}

.markdown-body .contains-task-list {
  padding-left: 1.6em;
  list-style: none;
}

.markdown-body .task-list-item input {
  width: 16px;
  height: 16px;
  margin: 0 0.5em 0 -1.5em;
  vertical-align: -2px;
  accent-color: var(--accent);
  cursor: pointer;
}

.markdown-body blockquote {
  margin-left: 0;
  margin-right: 0;
  padding: 0.5em 1em;
  border-left: 3px solid var(--accent);
  border-radius: 0 8px 8px 0;
  background: rgb(96 165 250 / 0.06);
  color: #b6c2d3;
}

.markdown-body blockquote > :last-child {
  margin-bottom: 0;
}

.markdown-body code {
  padding: 0.12em 0.38em;
  border: 1px solid var(--line-soft);
  border-radius: 6px;
  background: var(--code-bg);
  font-family: var(--mono);
  font-size: 0.86em;
}

.markdown-body pre {
  padding: 14px 16px;
  overflow: auto;
  border: 1px solid var(--line-soft);
  border-radius: var(--radius-sm);
  background: var(--code-bg);
  line-height: 1.55;
  scrollbar-color: #3b4a61 transparent;
  scrollbar-width: thin;
}

.markdown-body pre code {
  padding: 0;
  border: 0;
  background: none;
  font-size: 13px;
}

.markdown-body table {
  display: block;
  max-width: 100%;
  width: max-content;
  overflow: auto;
  border-collapse: collapse;
  font-size: 0.94em;
}

.markdown-body :is(th, td) {
  padding: 7px 13px;
  border: 1px solid var(--line);
}

.markdown-body th {
  background: rgb(15 23 42 / 0.55);
  color: var(--strong);
  font-weight: 600;
}

/* Cells keep their align attribute; only unaligned headers are set here. */
.markdown-body th:not([align]) {
  text-align: start;
}

.markdown-body tbody tr:nth-child(2n) {
  background: rgb(15 23 42 / 0.28);
}

.markdown-body img {
  max-width: 100%;
  height: auto;
  border-radius: 8px;
  vertical-align: middle;
}

.markdown-body hr {
  height: 0;
  margin: 2em 0;
  border: 0;
  border-top: 1px solid var(--line);
}

.preview-empty {
  color: var(--muted);
  font-style: italic;
}

.tok-keyword {
  color: #c4b5fd;
}

.tok-string {
  color: #86efac;
}

.tok-number {
  color: #fdba74;
}

.tok-comment {
  color: var(--faint);
  font-style: italic;
}

.tok-function {
  color: #7dd3fc;
}

/* ------------------------------------------------------------------------
   Footer, dialog, toast, drop hint */

.footer {
  grid-area: foot;
  display: flex;
  align-items: center;
  justify-content: center;
  border-top: 1px solid var(--line-soft);
  font-size: 13px;
}

.footer-link {
  display: inline-flex;
  align-items: center;
  gap: 0.45em;
  min-height: 40px;
  padding: 0 12px;
  border-radius: 8px;
  color: var(--muted);
  text-decoration: none;
  transition: color var(--fast) var(--ease);
}

.footer-link:hover {
  color: var(--accent);
}

.dialog {
  width: min(calc(100vw - 32px), 420px);
  padding: 0;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
  color: var(--text);
  box-shadow: var(--shadow-lg);
}

.dialog[open] {
  animation: dialog-in var(--slow) var(--ease);
}

.dialog::backdrop {
  background: rgb(2 6 23 / 0.65);
}

@keyframes dialog-in {
  from {
    opacity: 0;
    transform: translateY(8px) scale(0.98);
  }
}

.dialog-form {
  display: flex;
  flex-direction: column;
  gap: 16px;
  padding: 20px;
}

.dialog-message {
  margin: 0;
  font-size: 15px;
  line-height: 1.5;
  overflow-wrap: anywhere;
}

.dialog-input {
  min-height: 44px;
  padding: 0 12px;
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  background: var(--bg);
  font-size: 16px;
}

.dialog-input:focus-visible {
  outline-offset: 0;
}

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

.toast {
  position: fixed;
  bottom: 56px;
  left: 50%;
  z-index: 40;
  max-width: min(calc(100vw - 32px), 440px);
  padding: 10px 16px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #24324a;
  color: var(--strong);
  box-shadow: var(--shadow-lg);
  font-size: 14px;
  opacity: 0;
  pointer-events: none;
  transform: translate(-50%, 12px);
  transition: opacity var(--slow) var(--ease), transform var(--slow) var(--ease);
}

.toast.show {
  opacity: 1;
  transform: translate(-50%, 0);
}

.drop-hint {
  position: fixed;
  inset: 0;
  z-index: 50;
  display: grid;
  place-items: center;
  padding: 24px;
  background: rgb(15 23 42 / 0.82);
  pointer-events: none;
}

.drop-card {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
  margin: 0;
  padding: 32px 40px;
  border: 2px dashed var(--accent);
  border-radius: 16px;
  background: rgb(30 41 59 / 0.92);
  color: var(--strong);
  font-size: 17px;
  font-weight: 600;
  text-align: center;
}

.drop-card .icon {
  width: 36px;
  height: 36px;
  color: var(--accent);
}

/* ------------------------------------------------------------------------
   Narrow screens: the sidebar becomes a drawer */

@media (max-width: 1023px) {
  .app {
    grid-template-columns: minmax(0, 1fr);
    grid-template-areas:
      "top"
      "main"
      "foot";
  }

  .topbar {
    padding-left: 8px;
  }

  .menu-btn,
  .drawer-close {
    display: inline-flex;
  }

  .side-head {
    min-height: 40px;
  }

  .sidebar {
    position: fixed;
    top: 0;
    bottom: 0;
    left: 0;
    z-index: 30;
    width: min(320px, 88vw);
    border-right: 1px solid var(--line);
    box-shadow: var(--shadow-lg);
    transform: translateX(-102%);
    visibility: hidden;
    transition: transform var(--slow) var(--ease), visibility 0s linear var(--slow);
  }

  .drawer-open .sidebar {
    transform: none;
    visibility: visible;
    transition: transform var(--slow) var(--ease), visibility 0s;
  }

  .backdrop {
    display: block;
    position: fixed;
    inset: 0;
    z-index: 25;
    background: rgb(2 6 23 / 0.6);
    opacity: 0;
    visibility: hidden;
    transition: opacity var(--slow) var(--ease), visibility 0s linear var(--slow);
  }

  .drawer-open .backdrop {
    opacity: 1;
    visibility: visible;
    transition: opacity var(--slow) var(--ease), visibility 0s;
  }
}

/* ------------------------------------------------------------------------
   Phones: one pane at a time */

@media (max-width: 767px) {
  :root {
    --header-h: 52px;
  }

  .topbar {
    gap: 4px;
    padding: 0 6px;
  }

  .brand {
    flex: 1;
    gap: 8px;
    padding-right: 0;
    border-right: 0;
    font-size: 16px;
  }

  .logo {
    width: 26px;
    height: 26px;
  }

  .doc-title,
  .spacer {
    display: none;
  }

  .save-status {
    padding: 0 6px;
  }

  .lang-btn {
    min-width: 44px;
    padding: 0 8px;
  }

  .save-text,
  .label-wide {
    position: absolute;
    width: 1px;
    height: 1px;
    overflow: hidden;
    clip-path: inset(50%);
    white-space: nowrap;
  }

  .reset-btn {
    width: 40px;
    padding: 0;
  }

  .workspace {
    gap: 0;
    padding: 0;
  }

  .view-tabs {
    display: flex;
    gap: 4px;
    padding: 4px 6px;
    border-bottom: 1px solid var(--line-soft);
  }

  .tab {
    display: inline-flex;
    flex: 1;
    align-items: center;
    justify-content: center;
    gap: 8px;
    min-height: 40px;
    border: 0;
    border-radius: var(--radius-sm);
    background: transparent;
    color: var(--muted);
    font-size: 14px;
    font-weight: 600;
    cursor: pointer;
    transition: background-color var(--fast) var(--ease), color var(--fast) var(--ease);
  }

  .tab .icon {
    width: 18px;
    height: 18px;
  }

  .tab[aria-pressed="true"] {
    background: var(--surface);
    color: var(--strong);
    box-shadow: inset 0 -2px 0 var(--accent);
  }

  .panes {
    display: flex;
  }

  .splitter,
  .panes[data-view="edit"] .preview-pane,
  .panes[data-view="preview"] .editor-pane {
    display: none;
  }

  .pane {
    flex: 1;
    border: 0;
    border-radius: 0;
    box-shadow: none;
  }

  .toolbar {
    flex-wrap: nowrap;
    justify-content: space-between;
    gap: 0;
    padding: 4px 6px;
    overflow-x: auto;
    scrollbar-width: none;
    /* Scroll hints: an accent fade shows on an edge only while more buttons hide behind it. */
    background:
      linear-gradient(to right, var(--surface) 40%, rgb(30 41 59 / 0)) left / 28px 100% no-repeat local,
      linear-gradient(to left, var(--surface) 40%, rgb(30 41 59 / 0)) right / 28px 100% no-repeat local,
      radial-gradient(farthest-side at 0 50%, rgb(96 165 250 / 0.45), rgb(96 165 250 / 0)) left / 14px 100% no-repeat scroll,
      radial-gradient(farthest-side at 100% 50%, rgb(96 165 250 / 0.45), rgb(96 165 250 / 0)) right / 14px 100% no-repeat scroll,
      var(--surface);
  }

  .tool {
    flex: 0 0 40px;
  }

  .pane-head {
    min-height: 49px;
    padding: 4px 14px;
  }

  .editor {
    padding: 14px 14px 40px;
  }

  .preview {
    padding: 16px 16px 40px;
  }

  .toast {
    bottom: 52px;
  }
}

/* Touch screens: 16px text, so phones do not zoom in when the editor gets the focus. */
@media (pointer: coarse) {
  .editor {
    font-size: 16px;
  }

  /* A 40px touch target for the 12px divider, without changing the layout. */
  .splitter {
    position: relative;
    z-index: 1;
  }

  .splitter::before {
    content: "";
    position: absolute;
    inset: 0 -14px;
  }
}

/* Larger targets in the drawer and on touch screens. */
@media (max-width: 1023px), (pointer: coarse) {
  .toc-link {
    display: flex;
    align-items: center;
    min-height: 40px;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 1ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 1ms !important;
    transition-delay: 0s !important;
    scroll-behavior: auto !important;
  }
}