:root {
  color-scheme: light;
  --app-bg: #f2efe9;
  --panel: #fbfaf7;
  --panel-strong: #ffffff;
  --paper: #fffdfa;
  --paper-soft: #faf6ee;
  --ink: #26231f;
  --muted: #766f67;
  --faint: #a79e94;
  --line: #e5ded4;
  --line-strong: #d7cec1;
  --accent: #796046;
  --accent-soft: #efe4d5;
  --accent-strong: #4b3828;
  --success: #557b67;
  --shadow: 0 18px 55px rgba(67, 51, 34, 0.1);
  --sidebar-width: 270px;
  --document-size: 17px;
  font-family: Inter, "SF Pro Display", "PingFang SC", "Microsoft YaHei", system-ui, sans-serif;
}

* { box-sizing: border-box; }
[hidden] { display: none !important; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  min-width: 320px;
  background: var(--app-bg);
  color: var(--ink);
  transition: background 180ms ease, color 180ms ease;
}

button, select, input { font: inherit; }
button, a, select { -webkit-tap-highlight-color: transparent; }
button { color: inherit; }

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

.skip-link {
  position: fixed;
  top: 8px;
  left: 50%;
  z-index: 1000;
  translate: -50% -80px;
  padding: 9px 14px;
  border-radius: 9px;
  background: var(--ink);
  color: var(--panel);
  text-decoration: none;
  transition: translate 160ms ease;
}
.skip-link:focus { translate: -50% 0; }

.reader-shell { min-height: 100vh; display: grid; grid-template-columns: var(--sidebar-width) minmax(0, 1fr); transition: grid-template-columns 200ms ease; }

.app-sidebar {
  position: fixed;
  inset: 0 auto 0 0;
  z-index: 40;
  width: var(--sidebar-width);
  display: flex;
  flex-direction: column;
  padding: 22px 17px 18px;
  border-right: 1px solid var(--line);
  background: color-mix(in srgb, var(--panel) 95%, transparent);
  backdrop-filter: blur(18px);
  transition: transform 200ms ease;
}

.brand-row { display: flex; align-items: center; justify-content: space-between; padding: 0 5px 24px; }
.brand { display: flex; align-items: center; gap: 11px; color: var(--ink); text-decoration: none; }
.brand-mark {
  width: 39px;
  height: 39px;
  display: grid;
  place-items: center;
  border-radius: 10px;
  background: var(--ink);
  color: var(--panel);
  font-size: 16px;
  font-weight: 800;
  letter-spacing: -1px;
  box-shadow: 0 6px 16px rgba(39, 34, 29, 0.15);
}
.brand strong, .brand small { display: block; }
.brand strong { font-size: 15px; letter-spacing: .01em; }
.brand small { margin-top: 2px; color: var(--muted); font-size: 9px; font-weight: 700; letter-spacing: .16em; }

.sidebar-close, .menu-button { display: none !important; }
.sidebar-section { padding-bottom: 20px; }
.sidebar-label { margin: 0 8px 9px; color: var(--faint); font-size: 10px; font-weight: 800; letter-spacing: .14em; text-transform: uppercase; }
.sidebar-link {
  width: 100%;
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 5px;
  padding: 11px 12px;
  border: 0;
  border-radius: 11px;
  background: transparent;
  text-align: left;
  cursor: pointer;
}
.sidebar-link:hover { background: color-mix(in srgb, var(--accent-soft) 55%, transparent); }
.sidebar-link.is-active { background: var(--accent-soft); color: var(--accent-strong); }
.sidebar-link svg { flex: 0 0 auto; width: 19px; height: 19px; }
.sidebar-link span { min-width: 0; }
.sidebar-link strong, .sidebar-link small { display: block; }
.sidebar-link strong { font-size: 13px; font-weight: 650; }
.sidebar-link small { overflow: hidden; margin-top: 3px; color: var(--muted); font-size: 10px; text-overflow: ellipsis; white-space: nowrap; }

.toc-panel { min-height: 0; flex: 1; display: flex; flex-direction: column; padding-top: 14px; border-top: 1px solid var(--line); }
.toc-heading { display: flex; align-items: center; justify-content: space-between; }
.toc-heading > span { margin-right: 8px; color: var(--faint); font-size: 10px; }
.toc {
  overflow: auto;
  padding: 3px 4px 14px;
  scrollbar-width: thin;
  overscroll-behavior-y: contain;
}
.toc-empty { margin: 10px 6px; color: var(--faint); font-size: 11px; line-height: 1.7; }
.toc a {
  display: block;
  overflow: hidden;
  padding: 6px 8px;
  border-left: 2px solid transparent;
  color: var(--muted);
  font-size: 11px;
  line-height: 1.35;
  text-decoration: none;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.toc a:hover, .toc a.is-active { border-left-color: var(--accent); color: var(--ink); background: color-mix(in srgb, var(--accent-soft) 38%, transparent); }
.toc a[data-level="3"] { padding-left: 20px; font-size: 10px; }

.sidebar-footer { padding-top: 15px; border-top: 1px solid var(--line); }
.privacy-note { display: flex; gap: 9px; padding: 10px; border-radius: 10px; background: color-mix(in srgb, var(--success) 7%, transparent); color: var(--success); }
.privacy-note svg { width: 17px; height: 17px; flex: 0 0 auto; }
.privacy-note strong, .privacy-note small { display: block; }
.privacy-note strong { font-size: 10px; }
.privacy-note small { margin-top: 2px; color: var(--muted); font-size: 9px; }
.sidebar-collapse-toggle {
  position: fixed;
  left: calc(var(--sidebar-width) - 16px);
  top: 50%;
  z-index: 45;
  width: 32px;
  height: 58px;
  display: grid;
  place-items: center;
  padding: 0;
  border: 1px solid var(--line-strong);
  border-radius: 8px;
  background: var(--panel-strong);
  color: var(--ink);
  box-shadow: 0 8px 24px rgba(38, 32, 26, .14);
  cursor: pointer;
  translate: 0 -50%;
  transition: left 200ms ease, translate 180ms ease, border-color 180ms ease, background 180ms ease, box-shadow 180ms ease;
}
.sidebar-collapse-toggle:hover {
  translate: 4px -50%;
  border-color: var(--accent);
  background: var(--accent-soft);
  box-shadow: 0 12px 30px rgba(38, 32, 26, .22);
}
.sidebar-collapse-toggle:active { translate: 1px -50%; }
.sidebar-collapse-toggle svg { --toggle-rotation: 0deg; width: 17px; height: 17px; transform: rotate(var(--toggle-rotation)) translateX(0); transition: transform 180ms ease; }
.sidebar-collapse-toggle:hover svg { transform: rotate(var(--toggle-rotation)) translateX(-3px); }
.sidebar-collapsed .reader-shell { grid-template-columns: 0 minmax(0, 1fr); }
.sidebar-collapsed .app-sidebar { transform: translateX(-102%); }
.sidebar-collapsed .sidebar-collapse-toggle { left: 8px; }
.sidebar-collapsed .sidebar-collapse-toggle svg { --toggle-rotation: 180deg; }

.sidebar-scrim { display: none; }
.app-main { grid-column: 2; min-width: 0; }

.topbar {
  position: sticky;
  top: 0;
  z-index: 30;
  min-height: 66px;
  display: flex;
  align-items: center;
  gap: 24px;
  padding: 9px clamp(18px, 3vw, 48px);
  border-bottom: 1px solid var(--line);
  background: color-mix(in srgb, var(--app-bg) 90%, transparent);
  backdrop-filter: blur(20px);
}
.topbar-start { min-width: 0; flex: 1; }
.file-identity { display: flex; align-items: center; gap: 10px; min-width: 0; }
.status-dot { width: 8px; height: 8px; flex: 0 0 auto; border: 2px solid var(--faint); border-radius: 50%; }
.has-document .status-dot { border-color: var(--success); background: var(--success); box-shadow: 0 0 0 4px color-mix(in srgb, var(--success) 14%, transparent); }
.file-identity div { min-width: 0; }
.file-identity strong, .file-identity small { display: block; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.file-identity strong { max-width: 340px; font-size: 12px; }
.file-identity small { margin-top: 3px; color: var(--muted); font-size: 9px; }
.site-nav { display: flex; align-items: center; gap: 18px; }
.site-nav a { position: relative; padding: 8px 0; color: var(--muted); font-size: 11px; font-weight: 600; text-decoration: none; white-space: nowrap; }
.site-nav a:hover, .site-nav a[aria-current="page"] { color: var(--ink); }
.site-nav a[aria-current="page"]::after { content: ""; position: absolute; inset: auto 0 1px; height: 1px; background: var(--accent); }
.topbar-actions, .heading-actions, .toolbar-group { display: flex; align-items: center; gap: 8px; }

.button, .icon-button, .toolbar-button {
  border: 1px solid var(--line-strong);
  border-radius: 9px;
  background: var(--panel-strong);
  cursor: pointer;
  transition: border-color 140ms ease, background 140ms ease, transform 140ms ease, color 140ms ease;
}
.button:hover:not(:disabled), .icon-button:hover:not(:disabled), .toolbar-button:hover:not(:disabled) { border-color: var(--accent); transform: translateY(-1px); }
.button:disabled, .icon-button:disabled, .toolbar-button:disabled { cursor: not-allowed; opacity: .42; }
.button { min-height: 38px; display: inline-flex; align-items: center; justify-content: center; gap: 7px; padding: 0 13px; font-size: 11px; font-weight: 700; }
.button svg { width: 16px; height: 16px; }
.button-primary { border-color: var(--ink); background: var(--ink); color: var(--panel); }
.button-primary:hover:not(:disabled) { border-color: var(--accent-strong); background: var(--accent-strong); }
.button-secondary { background: transparent; }
.button-ghost { background: transparent; color: var(--muted); }
.button-large { min-height: 44px; padding: 0 18px; font-size: 12px; }
.icon-button { width: 38px; height: 38px; display: inline-grid; place-items: center; padding: 0; font-size: 11px; font-weight: 750; }

.workspace { padding: 30px clamp(18px, 3vw, 48px) 48px; }
.workspace-heading { max-width: 1480px; display: flex; align-items: flex-start; justify-content: space-between; gap: 20px; margin: 0 auto 18px; }
.eyebrow { margin: 0 0 9px; color: var(--accent); font-size: 10px; font-weight: 800; letter-spacing: .16em; }
.workspace-heading h1 { margin: 0; font-family: Georgia, "Songti SC", "STSong", serif; font-size: clamp(27px, 3vw, 42px); font-weight: 500; letter-spacing: -.02em; }
.workspace-heading > div > p:last-child { margin: 7px 0 0; color: var(--muted); font-size: 12px; }
.sun-icon { display: none; }
[data-color-mode="dark"] .moon-icon { display: none; }
[data-color-mode="dark"] .sun-icon { display: block; }

.reader-card {
  max-width: 1480px;
  min-height: calc(100vh - 196px);
  display: flex;
  flex-direction: column;
  margin: 0 auto;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 16px;
  background: var(--panel);
  box-shadow: var(--shadow);
}
.reader-toolbar { min-height: 58px; display: flex; align-items: center; justify-content: space-between; gap: 16px; padding: 9px 14px; border-bottom: 1px solid var(--line); background: var(--panel-strong); }
.toolbar-button { min-height: 35px; display: inline-flex; align-items: center; gap: 7px; padding: 0 10px; border-color: transparent; background: transparent; color: var(--muted); font-size: 10px; }
.toolbar-button svg { width: 17px; height: 17px; }
.toolbar-divider { width: 1px; height: 24px; background: var(--line); }
.theme-picker { min-height: 36px; display: flex; align-items: center; gap: 8px; padding: 0 5px 0 11px; border-radius: 9px; background: var(--paper-soft); color: var(--muted); font-size: 10px; }
.theme-picker select { max-width: 130px; padding: 5px 24px 5px 2px; border: 0; outline: 0; background: transparent; color: var(--ink); font-size: 11px; font-weight: 700; cursor: pointer; }
.reader-viewport { min-height: 560px; flex: 1; overflow: visible; position: relative; background: var(--paper-soft); }

.empty-state { min-height: 560px; display: flex; align-items: center; justify-content: center; flex-direction: column; padding: 70px 22px; text-align: center; background: radial-gradient(circle at 50% 38%, rgba(218, 197, 169, .2), transparent 32%), linear-gradient(180deg, var(--paper) 0%, var(--paper-soft) 100%); }
.drop-illustration { position: relative; width: 120px; height: 112px; margin-bottom: 14px; }
.paper-sheet { position: absolute; display: block; width: 68px; height: 84px; border: 1px solid var(--line-strong); border-radius: 7px; background: var(--paper); box-shadow: 0 12px 24px rgba(63, 45, 27, .09); }
.paper-sheet-back { left: 21px; top: 9px; rotate: -7deg; opacity: .72; }
.paper-sheet-front { left: 32px; top: 2px; rotate: 3deg; padding: 16px 13px; text-align: left; }
.paper-sheet-front b { display: block; margin-bottom: 11px; color: var(--accent); font-family: Georgia, serif; font-size: 20px; }
.paper-sheet-front i { display: block; width: 100%; height: 3px; margin-top: 7px; border-radius: 9px; background: var(--line-strong); }
.paper-sheet-front i:nth-child(3) { width: 76%; }
.upload-orbit { position: absolute; right: 7px; bottom: 8px; width: 36px; height: 36px; display: grid; place-items: center; border: 3px solid var(--paper-soft); border-radius: 50%; background: var(--ink); color: var(--paper); font-size: 19px; box-shadow: 0 5px 14px rgba(39, 34, 29, .2); }
.empty-kicker { margin: 0 0 12px; color: var(--accent); font-size: 9px; font-weight: 800; letter-spacing: .18em; }
.empty-state h2 { margin: 0; font-family: Georgia, "Songti SC", serif; font-size: clamp(25px, 3vw, 38px); font-weight: 500; }
.empty-state > p:not(.empty-kicker) { max-width: 600px; margin: 14px auto 0; color: var(--muted); font-size: 12px; line-height: 1.8; }
.empty-actions { display: flex; gap: 10px; margin-top: 24px; }
.file-limit { margin-top: 18px; color: var(--faint); font-size: 9px; }

.reader-statusbar { min-height: 38px; display: flex; align-items: center; justify-content: space-between; gap: 20px; padding: 8px 16px; border-top: 1px solid var(--line); background: var(--panel-strong); color: var(--faint); font-size: 9px; }
.reader-statusbar div { display: flex; align-items: center; gap: 17px; }
.reader-statusbar div span + span { position: relative; }
.reader-statusbar div span + span::before { content: ""; position: absolute; top: 50%; left: -9px; width: 2px; height: 2px; border-radius: 50%; background: var(--faint); }

.markdown-document {
  position: relative;
  width: min(100%, 1100px);
  min-height: 100%;
  margin: 0 auto;
  padding: clamp(46px, 7vw, 94px) clamp(30px, 8vw, 110px) 110px;
  background: var(--paper);
  color: var(--ink);
  font-family: "Noto Serif SC", "Source Han Serif SC", "Songti SC", SimSun, Georgia, serif;
  font-size: var(--document-size);
  line-height: 1.9;
  overflow-wrap: anywhere;
  box-shadow: 0 0 0 1px color-mix(in srgb, var(--line) 70%, transparent), 0 18px 60px rgba(68, 49, 29, .08);
}
.markdown-document:focus { outline: none; }
.markdown-document > :first-child { margin-top: 0; }
.markdown-document > :last-child { margin-bottom: 0; }
.markdown-document h1, .markdown-document h2, .markdown-document h3, .markdown-document h4 { position: relative; color: var(--ink); font-family: Georgia, "Noto Serif SC", "Songti SC", serif; line-height: 1.32; scroll-margin-top: 94px; }
.markdown-document h1 { margin: 0 0 .85em; padding-bottom: .42em; border-bottom: 2px solid var(--ink); font-size: 2.45em; font-weight: 600; letter-spacing: -.025em; }
.markdown-document h2 { margin: 2.2em 0 .85em; padding-bottom: .34em; border-bottom: 1px solid var(--line-strong); font-size: 1.65em; font-weight: 600; }
.markdown-document h3 { margin: 1.8em 0 .7em; font-size: 1.25em; font-weight: 700; }
.markdown-document h4 { margin: 1.5em 0 .6em; font-size: 1.05em; }
.markdown-document p { margin: 1em 0; }
.markdown-document strong { font-weight: 750; }
.markdown-document a { color: var(--accent); text-decoration-color: color-mix(in srgb, var(--accent) 45%, transparent); text-underline-offset: 3px; }
.markdown-document a:hover { text-decoration-color: var(--accent); }
.markdown-document ul, .markdown-document ol { margin: .9em 0; padding-left: 1.7em; }
.markdown-document li { margin: .3em 0; }
.markdown-document li::marker { color: var(--accent); }
.markdown-document blockquote { margin: 1.6em 0; padding: .8em 1.25em; border-left: 4px solid #cdb08d; background: var(--paper-soft); color: var(--muted); }
.markdown-document blockquote > :first-child { margin-top: 0; }
.markdown-document blockquote > :last-child { margin-bottom: 0; }
.markdown-document hr { height: 1px; margin: 2.5em 0; border: 0; background: var(--line-strong); }
.markdown-document code { padding: .16em .38em; border-radius: 5px; background: color-mix(in srgb, var(--accent-soft) 62%, transparent); color: var(--accent-strong); font-family: "Cascadia Code", "SFMono-Regular", Consolas, monospace; font-size: .86em; }
.markdown-document pre { position: relative; overflow: auto; margin: 1.6em 0; padding: 1.25em 1.35em; border: 1px solid #3d3c3a; border-radius: 10px; background: #292927; color: #e7e1d8; line-height: 1.65; box-shadow: 0 12px 28px rgba(30, 28, 24, .13); }
.markdown-document pre code { padding: 0; background: transparent; color: inherit; font-size: .82em; white-space: pre; }
.markdown-document pre[data-language]::after { content: attr(data-language); position: absolute; top: 8px; right: 10px; color: #948f86; font-family: Inter, sans-serif; font-size: 9px; font-weight: 700; letter-spacing: .08em; text-transform: uppercase; }
.markdown-document .table-wrap { overflow-x: auto; margin: 1.6em 0; }
.markdown-document table { width: 100%; border-collapse: collapse; border-spacing: 0; font-family: Inter, "PingFang SC", sans-serif; font-size: .86em; line-height: 1.6; }
.markdown-document th, .markdown-document td { padding: .72em .85em; border: 1px solid var(--line-strong); text-align: left; vertical-align: top; }
.markdown-document th { background: var(--paper-soft); font-weight: 750; }
.markdown-document tbody tr:nth-child(even) { background: color-mix(in srgb, var(--paper-soft) 55%, transparent); }
.markdown-document img { display: block; max-width: 100%; height: auto; margin: 1.5em auto; border-radius: 8px; box-shadow: 0 8px 30px rgba(40, 34, 27, .1); }
.markdown-document input[type="checkbox"] { margin-right: .55em; accent-color: var(--accent); }
.markdown-document .mermaid { overflow: auto; margin: 1.7em 0; padding: 1.3em; border: 1px solid var(--line); border-radius: 10px; background: var(--paper-soft); text-align: center; }
.markdown-document .mermaid svg {
  display: block;
  width: 100% !important;
  max-width: 100% !important;
  height: auto !important;
  min-height: 180px;
  margin: 0 auto;
  fill: initial;
  stroke: initial;
  stroke-width: initial;
  stroke-linecap: initial;
  stroke-linejoin: initial;
}
.markdown-document .footnotes { margin-top: 3em; padding-top: 1em; border-top: 1px solid var(--line); color: var(--muted); font-size: .86em; }

[data-document-theme="clean"] .markdown-document { width: min(100%, 960px); font-family: Inter, "PingFang SC", sans-serif; line-height: 1.82; box-shadow: none; }
[data-document-theme="clean"] .markdown-document h1, [data-document-theme="clean"] .markdown-document h2, [data-document-theme="clean"] .markdown-document h3 { font-family: Inter, "PingFang SC", sans-serif; }
[data-document-theme="clean"] .markdown-document h1 { border-bottom-width: 1px; font-size: 2.25em; }
[data-document-theme="academic"] .markdown-document { width: min(100%, 900px); font-family: "Times New Roman", "Songti SC", serif; line-height: 2; }
[data-document-theme="academic"] .markdown-document h1 { border-bottom: 0; text-align: center; font-size: 2.15em; }
[data-document-theme="academic"] .markdown-document h2 { border-bottom: 0; font-size: 1.45em; }
[data-document-theme="academic"] .markdown-document p { text-align: justify; text-indent: 2em; }
[data-document-theme="academic"] .markdown-document li p, [data-document-theme="academic"] .markdown-document blockquote p { text-indent: 0; }

[data-document-theme="clean"] .reader-viewport { background: #e8eff3; }
[data-document-theme="clean"] .markdown-document {
  width: min(100%, 1180px);
  padding: clamp(38px, 5vw, 68px) clamp(34px, 7vw, 92px) 90px;
  border-left: 6px solid #5c879c;
  background: #f8fbfc;
  color: #24343d;
  box-shadow: none;
}
[data-document-theme="clean"] .markdown-document h1,
[data-document-theme="clean"] .markdown-document h2,
[data-document-theme="clean"] .markdown-document h3 { color: #183b4c; }
[data-document-theme="clean"] .markdown-document h1 { padding-bottom: .5em; border-bottom: 3px solid #5c879c; }
[data-document-theme="clean"] .markdown-document h2 { border-bottom-color: #b7cbd5; }
[data-document-theme="clean"] .markdown-document a,
[data-document-theme="clean"] .markdown-document li::marker { color: #326b86; }
[data-document-theme="clean"] .markdown-document blockquote { border-left-color: #5c879c; background: #eaf2f5; color: #52656f; }
[data-document-theme="clean"] .markdown-document code { background: #dfebf0; color: #17485d; }
[data-document-theme="clean"] .markdown-document th { background: #dce9ef; }
[data-document-theme="clean"] .markdown-document th,
[data-document-theme="clean"] .markdown-document td { border-color: #b8ccd6; }
[data-document-theme="clean"] .markdown-document .mermaid { border-color: #b8ccd6; background: #eef5f7; }

[data-document-theme="academic"] .reader-viewport { background: #ddd7cc; }
[data-document-theme="academic"] .markdown-document {
  width: min(100%, 860px);
  padding: clamp(58px, 7vw, 92px) clamp(44px, 8vw, 94px) 116px;
  border: 1px solid #c8bead;
  background: #fffdf6;
  color: #24211d;
  box-shadow: 0 24px 70px rgba(58, 48, 37, .16);
}
[data-document-theme="academic"] .markdown-document h1,
[data-document-theme="academic"] .markdown-document h2,
[data-document-theme="academic"] .markdown-document h3 { color: #303d53; }
[data-document-theme="academic"] .markdown-document h1 { padding-bottom: .7em; border-bottom: 3px double #8a4e43; }
[data-document-theme="academic"] .markdown-document h2 { padding-bottom: .45em; border-bottom: 1px solid #b8aa95; }
[data-document-theme="academic"] .markdown-document a,
[data-document-theme="academic"] .markdown-document li::marker { color: #7a4037; }
[data-document-theme="academic"] .markdown-document blockquote { border-left-color: #8a4e43; background: #f3ede2; color: #5e554b; }
[data-document-theme="academic"] .markdown-document code { background: #eee6d9; color: #63352f; }
[data-document-theme="academic"] .markdown-document th { background: #eee8dd; }
[data-document-theme="academic"] .markdown-document th,
[data-document-theme="academic"] .markdown-document td { border-color: #cfc4b3; }
[data-document-theme="academic"] .markdown-document .mermaid { border-color: #cfc4b3; background: #f7f2e8; }

[data-color-mode="dark"] {
  color-scheme: dark;
  --app-bg: #171716;
  --panel: #1d1d1b;
  --panel-strong: #232321;
  --paper: #20201e;
  --paper-soft: #292724;
  --ink: #eee9e1;
  --muted: #aaa39a;
  --faint: #777169;
  --line: #34322f;
  --line-strong: #48443f;
  --accent: #caaa85;
  --accent-soft: #362e25;
  --accent-strong: #e4c49e;
  --success: #8fbaa0;
  --shadow: 0 18px 60px rgba(0, 0, 0, .28);
}
[data-color-mode="dark"] .brand-mark, [data-color-mode="dark"] .button-primary, [data-color-mode="dark"] .upload-orbit { background: #ece5da; color: #211e1b; }
[data-color-mode="dark"] .markdown-document pre { background: #141413; }
[data-color-mode="dark"][data-document-theme="clean"] .reader-viewport { background: #121a1e; }
[data-color-mode="dark"][data-document-theme="clean"] .markdown-document { border-left-color: #6fa4bd; background: #182328; color: #dbe7ec; }
[data-color-mode="dark"][data-document-theme="clean"] .markdown-document h1,
[data-color-mode="dark"][data-document-theme="clean"] .markdown-document h2,
[data-color-mode="dark"][data-document-theme="clean"] .markdown-document h3 { color: #d8edf6; }
[data-color-mode="dark"][data-document-theme="clean"] .markdown-document h1 { border-bottom-color: #6fa4bd; }
[data-color-mode="dark"][data-document-theme="clean"] .markdown-document h2 { border-bottom-color: #3b5967; }
[data-color-mode="dark"][data-document-theme="clean"] .markdown-document blockquote { border-left-color: #6fa4bd; background: #213239; color: #a9bec7; }
[data-color-mode="dark"][data-document-theme="clean"] .markdown-document code,
[data-color-mode="dark"][data-document-theme="clean"] .markdown-document th { background: #263a43; color: #cde9f5; }
[data-color-mode="dark"][data-document-theme="clean"] .markdown-document th,
[data-color-mode="dark"][data-document-theme="clean"] .markdown-document td,
[data-color-mode="dark"][data-document-theme="clean"] .markdown-document .mermaid { border-color: #3b5967; }
[data-color-mode="dark"][data-document-theme="academic"] .reader-viewport { background: #171613; }
[data-color-mode="dark"][data-document-theme="academic"] .markdown-document { border-color: #504a40; background: #211f1a; color: #e8e1d6; }
[data-color-mode="dark"][data-document-theme="academic"] .markdown-document h1,
[data-color-mode="dark"][data-document-theme="academic"] .markdown-document h2,
[data-color-mode="dark"][data-document-theme="academic"] .markdown-document h3 { color: #d9e1ef; }
[data-color-mode="dark"][data-document-theme="academic"] .markdown-document h1 { border-bottom-color: #ba7669; }
[data-color-mode="dark"][data-document-theme="academic"] .markdown-document h2 { border-bottom-color: #5d564a; }
[data-color-mode="dark"][data-document-theme="academic"] .markdown-document blockquote { border-left-color: #ba7669; background: #2d2922; color: #bdb3a5; }
[data-color-mode="dark"][data-document-theme="academic"] .markdown-document code,
[data-color-mode="dark"][data-document-theme="academic"] .markdown-document th { background: #342f27; color: #efd1ca; }
[data-color-mode="dark"][data-document-theme="academic"] .markdown-document th,
[data-color-mode="dark"][data-document-theme="academic"] .markdown-document td,
[data-color-mode="dark"][data-document-theme="academic"] .markdown-document .mermaid { border-color: #5d564a; }

.drop-overlay { position: fixed; inset: 0; z-index: 100; display: grid; place-items: center; padding: 30px; background: rgba(34, 30, 26, .68); opacity: 0; visibility: hidden; backdrop-filter: blur(7px); transition: opacity 140ms ease, visibility 140ms ease; pointer-events: none; }
.drop-overlay.is-visible { opacity: 1; visibility: visible; }
.drop-overlay > div { width: min(520px, 100%); display: grid; place-items: center; padding: 56px 30px; border: 2px dashed rgba(255,255,255,.65); border-radius: 18px; background: rgba(26, 23, 20, .62); color: white; text-align: center; }
.drop-overlay span { width: 54px; height: 54px; display: grid; place-items: center; margin-bottom: 17px; border-radius: 50%; background: white; color: #2a251f; font-size: 25px; }
.drop-overlay strong { font-family: Georgia, "Songti SC", serif; font-size: 25px; }
.drop-overlay small { margin-top: 8px; color: rgba(255,255,255,.7); }

.toast-region { position: fixed; right: 22px; bottom: 22px; z-index: 120; display: grid; gap: 8px; pointer-events: none; }
.toast { min-width: 220px; max-width: min(360px, calc(100vw - 44px)); padding: 11px 14px; border: 1px solid var(--line-strong); border-radius: 10px; background: var(--panel-strong); box-shadow: var(--shadow); color: var(--ink); font-size: 11px; animation: toast-in 180ms ease both; }
.toast[data-tone="error"] { border-color: #b66d64; }
@keyframes toast-in { from { opacity: 0; translate: 0 8px; } }

.reader-shell.is-fullscreen .app-sidebar, .reader-shell.is-fullscreen .sidebar-collapse-toggle, .reader-shell.is-fullscreen .topbar, .reader-shell.is-fullscreen .workspace-heading, .reader-shell.is-fullscreen .reader-statusbar { display: none; }
.reader-shell.is-fullscreen { display: block; }
.reader-shell.is-fullscreen .app-main { min-height: 100vh; }
.reader-shell.is-fullscreen .workspace { padding: 0; }
.reader-shell.is-fullscreen .reader-card { max-width: none; min-height: 100vh; border: 0; border-radius: 0; }
.reader-shell.is-fullscreen .reader-toolbar { position: fixed; z-index: 60; top: 14px; right: 16px; width: auto; border: 1px solid var(--line); border-radius: 12px; box-shadow: var(--shadow); opacity: .2; transition: opacity 160ms ease; }
.reader-shell.is-fullscreen .reader-toolbar:hover, .reader-shell.is-fullscreen .reader-toolbar:focus-within { opacity: 1; }
.reader-shell.is-fullscreen .toolbar-group:first-child, .reader-shell.is-fullscreen .theme-picker span { display: none; }
.reader-shell.is-fullscreen .reader-viewport { min-height: 100vh; }
.reader-shell.is-fullscreen .markdown-document { min-height: 100vh; }

@media (max-width: 1080px) {
  .reader-shell { display: block; }
  .app-main { grid-column: auto; }
  .app-sidebar { transform: translateX(-102%); transition: transform 180ms ease; box-shadow: 14px 0 50px rgba(0,0,0,.18); }
  .sidebar-open .app-sidebar { transform: translateX(0); }
  .sidebar-scrim { position: fixed; inset: 0; z-index: 35; display: block; background: rgba(30,27,24,.38); opacity: 0; visibility: hidden; transition: opacity 180ms ease, visibility 180ms ease; }
  .sidebar-open .sidebar-scrim { opacity: 1; visibility: visible; }
  .sidebar-close, .menu-button { display: inline-grid !important; }
  .topbar-start { display: flex; align-items: center; gap: 10px; }
  .site-nav { display: none; }
  .sidebar-collapse-toggle { display: none; }
  .sidebar-collapsed.sidebar-open .app-sidebar { transform: translateX(0); }
}

@media (max-width: 720px) {
  .topbar { min-height: 60px; padding: 8px 12px; }
  .file-identity strong { max-width: 180px; }
  .topbar-actions .button-secondary { display: none; }
  .topbar-actions .button { min-width: 38px; padding: 0 10px; font-size: 0; }
  .topbar-actions .button svg { margin: 0; }
  .workspace { padding: 22px 10px 26px; }
  .workspace-heading { padding: 0 7px; }
  .workspace-heading > div > p:last-child { max-width: 88%; line-height: 1.6; }
  .reader-card { min-height: calc(100vh - 174px); border-radius: 12px; }
  .reader-toolbar { align-items: flex-start; padding: 8px; }
  .toolbar-button span, .toolbar-divider, .theme-picker span { display: none; }
  .toolbar-button { width: 36px; justify-content: center; padding: 0; }
  .theme-picker { padding: 0 4px; }
  .theme-picker select { max-width: 106px; }
  .toolbar-end { gap: 4px; }
  .toolbar-end .icon-button { width: 34px; height: 34px; }
  .reader-viewport, .empty-state { min-height: 500px; }
  .empty-state { padding: 55px 18px; }
  .empty-actions { flex-direction: column; width: min(260px, 100%); }
  .reader-statusbar { align-items: flex-start; flex-direction: column; gap: 6px; }
  .markdown-document { padding: 44px 25px 76px; font-size: calc(var(--document-size) - 1px); }
  .markdown-document h1 { font-size: 2em; }
  .markdown-document h2 { font-size: 1.45em; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { scroll-behavior: auto !important; animation-duration: .01ms !important; transition-duration: .01ms !important; }
}

@page { size: A4; margin: 18mm 17mm 20mm; }

@media print {
  :root { --document-size: 11pt !important; }
  body, body[data-color-mode="dark"] { --paper: #fff; --paper-soft: #f8f6f2; --ink: #201e1b; --muted: #625d57; --line: #e1dcd4; --line-strong: #cfc7bc; --accent: #72583f; --accent-soft: #eee4d8; --accent-strong: #443224; background: #fff !important; color: #201e1b !important; print-color-adjust: exact; -webkit-print-color-adjust: exact; }
  .skip-link, .app-sidebar, .sidebar-collapse-toggle, .topbar, .workspace-heading, .reader-toolbar, .reader-statusbar, .drop-overlay, .toast-region { display: none !important; }
  .reader-shell, .app-main, .workspace, .reader-card, .reader-viewport { display: block; min-height: auto; margin: 0; padding: 0; overflow: visible; border: 0; border-radius: 0; background: #fff; box-shadow: none; }
  .markdown-document { width: auto !important; min-height: auto; margin: 0; padding: 0; background: #fff; box-shadow: none; }
  .markdown-document h1, .markdown-document h2, .markdown-document h3 { break-after: avoid-page; }
  .markdown-document pre, .markdown-document blockquote, .markdown-document table, .markdown-document img, .markdown-document .mermaid { break-inside: avoid-page; }
  .markdown-document a { color: inherit; text-decoration: none; }
  .markdown-document pre { white-space: pre-wrap; }
}

/* Local annotations, pasted media and freehand drawing */
.annotation-toolbar {
  position: fixed;
  top: 50%;
  right: 18px;
  z-index: 220;
  translate: 0 -50%;
  width: 50px;
  max-height: calc(100vh - 24px);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 3px;
  padding: 6px 4px;
  border: 1px solid var(--line-strong);
  border-radius: 13px;
  background: color-mix(in srgb, var(--panel-strong) 94%, transparent);
  color: var(--ink);
  box-shadow: 0 15px 42px rgba(31, 27, 23, .2);
  backdrop-filter: blur(18px);
  overflow-y: auto;
  overscroll-behavior-y: contain;
}
.sidebar-collapsed .annotation-toolbar { right: 18px; }
.annotation-tool, .selection-toolbar button, .comment-editor button {
  min-height: 31px;
  padding: 0 10px;
  border: 1px solid transparent;
  border-radius: 8px;
  background: transparent;
  color: var(--muted);
  font-size: 10px;
  font-weight: 700;
  cursor: pointer;
}
.annotation-toolbar .annotation-tool { min-height: 29px; padding: 0 3px; font-size: 9px; }
.annotation-tool:hover, .selection-toolbar button:hover, .comment-editor button:hover { background: var(--accent-soft); color: var(--ink); }
.annotation-tool.is-active { border-color: var(--accent); background: var(--accent-soft); color: var(--accent-strong); }
.annotation-toolbar :disabled { cursor: not-allowed; opacity: .38; }
.annotation-toolbar .annotation-tool { width: 100%; white-space: nowrap; }
.annotation-toolbar-divider { width: 34px; height: 1px; margin: 2px 0; background: var(--line); }
.annotation-control { display: flex; flex-direction: column; align-items: center; gap: 4px; padding: 3px 2px; color: var(--muted); font-size: 9px; font-weight: 700; }
.annotation-control input[type="color"], .selection-toolbar input[type="color"] { width: 25px; height: 25px; padding: 2px; border: 1px solid var(--line-strong); border-radius: 7px; background: var(--panel-strong); cursor: pointer; }
.annotation-size-control input { width: 22px; height: 76px; accent-color: var(--accent); writing-mode: vertical-lr; direction: rtl; }
.annotation-size-control output { min-width: 18px; color: var(--ink); text-align: center; }
.annotation-clear { color: #a34d4d; }

.selection-toolbar, .comment-editor {
  position: fixed;
  z-index: 260;
  border: 1px solid var(--line-strong);
  background: var(--panel-strong);
  color: var(--ink);
  box-shadow: 0 13px 36px rgba(31, 27, 23, .22);
}
.selection-toolbar { display: flex; align-items: center; gap: 4px; padding: 5px; border-radius: 11px; }
.selection-toolbar label { display: flex; align-items: center; gap: 5px; min-height: 31px; padding: 0 7px; border-radius: 8px; color: var(--muted); font-size: 9px; font-weight: 700; cursor: pointer; }
.selection-toolbar label:hover { background: var(--accent-soft); color: var(--ink); }
.selection-delete-action { color: #a34d4d !important; }
.selection-toolbar::after, .comment-editor::after { content: ""; position: absolute; left: 20px; bottom: -6px; width: 10px; height: 10px; rotate: 45deg; border-right: 1px solid var(--line-strong); border-bottom: 1px solid var(--line-strong); background: var(--panel-strong); }
.comment-editor { width: min(320px, calc(100vw - 24px)); padding: 10px; border-radius: 12px; }
.comment-editor textarea { width: 100%; resize: vertical; padding: 9px 10px; border: 1px solid var(--line-strong); border-radius: 8px; outline: none; background: var(--paper); color: var(--ink); font-size: 11px; line-height: 1.55; }
.comment-editor textarea:focus { border-color: var(--accent); box-shadow: 0 0 0 3px color-mix(in srgb, var(--accent) 12%, transparent); }
.comment-editor > div { display: flex; justify-content: flex-end; gap: 5px; margin-top: 7px; }
.comment-editor button.is-primary { background: var(--ink); color: var(--panel); }

.annotation-inline { border-radius: 2px; box-decoration-break: clone; -webkit-box-decoration-break: clone; }
.annotation-comment-anchor { border-bottom: 2px dotted var(--accent); cursor: pointer; }
.annotation-comment-marker {
  position: relative;
  z-index: 58;
  display: inline-grid;
  place-items: center;
  width: 21px;
  height: 21px;
  margin: 0 3px;
  padding: 0;
  border: 1px solid var(--accent);
  border-radius: 50%;
  background: var(--accent-soft);
  color: var(--accent-strong);
  font: 800 10px/1 Inter, sans-serif;
  vertical-align: super;
  cursor: pointer;
}
.annotation-media-layer, .annotation-comment-layer, .annotation-drawing-layer { position: absolute; inset: 0; width: 100%; height: 100%; }
.annotation-media-layer { z-index: 40; pointer-events: none; }
.annotation-comment-layer { z-index: 60; pointer-events: none; }
.annotation-drawing-layer { z-index: 90; pointer-events: none; touch-action: none; }
body[data-annotation-mode="pencil"] .annotation-drawing-layer,
body[data-annotation-mode="watercolor"] .annotation-drawing-layer,
body[data-annotation-mode="highlighter"] .annotation-drawing-layer,
body[data-annotation-mode="eraser"] .annotation-drawing-layer { pointer-events: auto; cursor: crosshair; }
body[data-annotation-mode="eraser"] .annotation-drawing-layer { cursor: none; }
body[data-annotation-mode="comment"] .markdown-document { cursor: copy; }
.eraser-preview {
  position: fixed;
  z-index: 320;
  width: 20px;
  height: 20px;
  translate: -50% -50%;
  border: 1.5px solid rgba(20, 20, 20, .92);
  border-radius: 50%;
  background: rgba(255, 255, 255, .16);
  box-shadow: 0 0 0 1px rgba(255, 255, 255, .82);
  pointer-events: none;
}
.annotation-media-item {
  position: absolute;
  min-width: 80px;
  width: min(360px, 55%);
  padding: 4px;
  border: 1px solid transparent;
  border-radius: 8px;
  background: color-mix(in srgb, var(--paper) 75%, transparent);
  box-shadow: 0 10px 26px rgba(28, 24, 20, .17);
  pointer-events: auto;
  touch-action: none;
  cursor: move;
}
.annotation-media-item:hover, .annotation-media-item.is-selected { border-color: var(--accent); }
.annotation-media-item img { display: block; width: 100%; height: auto; max-width: none; margin: 0; border-radius: 5px; user-select: none; pointer-events: none; }
.annotation-media-delete, .annotation-media-resize {
  position: absolute;
  z-index: 2;
  display: grid;
  place-items: center;
  padding: 0;
  border: 1px solid var(--line-strong);
  background: var(--panel-strong);
  color: var(--ink);
  box-shadow: 0 4px 12px rgba(28, 24, 20, .18);
  cursor: pointer;
}
.annotation-media-delete { top: -11px; right: -11px; width: 23px; height: 23px; border-radius: 50%; font-size: 14px; }
.annotation-media-resize { right: -7px; bottom: -7px; width: 17px; height: 17px; border-radius: 5px; cursor: nwse-resize; }
.annotation-comment-card {
  position: absolute;
  width: min(270px, 72%);
  padding: 10px 11px;
  border: 1px solid var(--line-strong);
  border-left: 3px solid var(--accent);
  border-radius: 9px;
  background: color-mix(in srgb, var(--panel-strong) 96%, transparent);
  color: var(--ink);
  font: 11px/1.65 Inter, "PingFang SC", sans-serif;
  box-shadow: 0 10px 28px rgba(31, 27, 23, .16);
  pointer-events: auto;
}
.annotation-comment-card header { display: flex; align-items: center; justify-content: space-between; gap: 8px; margin-bottom: 4px; color: var(--accent); font-size: 9px; font-weight: 800; letter-spacing: .08em; }
.annotation-comment-actions { display: flex; align-items: center; gap: 2px; }
.annotation-comment-delete { color: #a34d4d !important; }
.annotation-comment-card button { padding: 2px 5px; border: 0; background: transparent; color: var(--muted); font-size: 9px; cursor: pointer; }
.annotation-comment-card p { margin: 0; white-space: pre-wrap; }
.annotation-comment-card.is-collapsed p { display: none; }

@media (max-width: 1080px) {
  .annotation-toolbar { right: 10px; max-height: calc(100vh - 20px); }
  .annotation-tool { white-space: nowrap; }
}
@media (max-width: 680px) {
  .annotation-toolbar { right: 6px; width: 48px; padding-inline: 3px; }
  .annotation-control > span, .annotation-size-control output { display: none; }
  .annotation-size-control input { width: 22px; height: 58px; }
  .selection-toolbar { max-width: calc(100vw - 16px); overflow-x: auto; }
}
@media print {
  .annotation-toolbar, .selection-toolbar, .comment-editor, .eraser-preview, .annotation-media-delete, .annotation-media-resize, .annotation-comment-marker, .annotation-comment-card { display: none !important; }
  .annotation-drawing-layer { print-color-adjust: exact; -webkit-print-color-adjust: exact; }
  .annotation-media-item { border: 0; background: transparent; box-shadow: none; }
}