:root {
  color-scheme: light;
  --paper: #f1ecdf;
  --paper-deep: #e6dece;
  --panel: rgba(255, 253, 247, .74);
  --ink: #1d1c19;
  --muted: #756e63;
  --line: rgba(48, 39, 28, .16);
  --accent: #a53325;
  --accent-dark: #76261e;
  --gold: #a97d37;
  --reader-font-size: 20px;
  --reader-leading: 1.78;
  --serif: "Iowan Old Style", "Palatino Linotype", Palatino, Georgia, serif;
  --display: Baskerville, "Baskerville Old Face", "Iowan Old Style", Georgia, serif;
  --zh: "Songti SC", STSong, "Noto Serif CJK SC", serif;
  --sans: Avenir Next, Avenir, "Helvetica Neue", sans-serif;
  --shadow: 0 28px 90px rgba(66, 45, 23, .14);
}

html[data-theme="night"] {
  color-scheme: dark;
  --paper: #171814;
  --paper-deep: #20211c;
  --panel: rgba(37, 38, 32, .78);
  --ink: #eee7d9;
  --muted: #aaa294;
  --line: rgba(238, 231, 217, .13);
  --accent: #da7561;
  --accent-dark: #ed9a88;
  --gold: #d5b36d;
  --shadow: 0 28px 90px rgba(0, 0, 0, .4);
}

html[data-theme="white"] {
  --paper: #fbfbf9;
  --paper-deep: #f0f0ec;
  --panel: rgba(255, 255, 255, .86);
  --ink: #171717;
  --muted: #717171;
  --line: rgba(0, 0, 0, .13);
  --accent: #8d2c22;
  --accent-dark: #681f18;
  --gold: #86642c;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 74px; }
body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--zh);
  transition: background .25s, color .25s;
}
body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -2;
  pointer-events: none;
  opacity: .45;
  background:
    radial-gradient(circle at 10% 0%, rgba(184, 121, 68, .14), transparent 30%),
    radial-gradient(circle at 91% 82%, rgba(118, 77, 41, .08), transparent 28%),
    repeating-linear-gradient(90deg, transparent 0 3px, rgba(76, 54, 31, .018) 3px 4px);
}
button, input { font: inherit; }
button, a { -webkit-tap-highlight-color: transparent; }
button { color: inherit; }
a { color: inherit; }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; }
[hidden] { display: none !important; }
.top-progress { position: fixed; inset: 0 0 auto; z-index: 200; height: 3px; }
.top-progress i { display: block; width: 0; height: 100%; background: var(--accent); transition: width .2s; }
.app-bar {
  position: sticky;
  top: 0;
  z-index: 100;
  height: 68px;
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  padding: 0 clamp(18px, 4vw, 58px);
  border-bottom: 1px solid var(--line);
  background: color-mix(in srgb, var(--paper) 86%, transparent);
  backdrop-filter: blur(18px);
}
.wordmark { display: inline-grid; grid-template-columns: 38px auto; gap: 10px; align-items: center; justify-self: start; text-decoration: none; }
.wordmark-icon { width: 38px; height: 42px; display: grid; place-items: center; border: 1px solid var(--ink); color: var(--accent); font: 700 11px/1 var(--sans); letter-spacing: -.03em; position: relative; }
.wordmark-icon::after { content: ""; position: absolute; inset: 4px -5px -5px 4px; border-right: 1px solid var(--accent); border-bottom: 1px solid var(--accent); z-index: -1; }
.wordmark b { display: block; font: 600 17px/1 var(--display); }
.wordmark small { color: var(--muted); font: 10px/1.3 var(--sans); letter-spacing: .11em; }
.app-bar-center { color: var(--muted); font: 700 9px/1 var(--sans); letter-spacing: .16em; text-transform: uppercase; max-width: 40vw; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.app-bar-actions { justify-self: end; display: flex; gap: 8px; }
.quiet-button { min-height: 36px; padding: 0 13px; border: 1px solid var(--line); background: var(--panel); cursor: pointer; border-radius: 2px; font: 600 12px/1 var(--zh); }
.quiet-button:hover { border-color: var(--accent); color: var(--accent); }
.kicker { margin: 0; color: var(--accent); font: 800 10px/1.4 var(--sans); letter-spacing: .17em; text-transform: uppercase; }
.library-view { min-height: calc(100vh - 68px); }
.library-hero {
  min-height: 610px;
  display: grid;
  grid-template-columns: minmax(420px, 720px) minmax(300px, 420px);
  justify-content: center;
  align-items: center;
  gap: clamp(48px, 8vw, 120px);
  padding: 80px clamp(28px, 8vw, 120px) 90px;
  border-bottom: 1px solid var(--line);
  position: relative;
}
.library-hero::after { content: "LOCAL / PRIVATE / REFLOWABLE"; position: absolute; right: 24px; bottom: 24px; color: var(--line); font: 700 9px/1 var(--sans); letter-spacing: .3em; writing-mode: vertical-rl; }
.hero-copy h1 { margin: 20px 0 24px; font: 500 clamp(53px, 6.2vw, 92px)/.92 var(--display); letter-spacing: -.045em; }
.hero-copy h1 em { display: block; color: var(--accent); font-weight: 400; }
.hero-description { max-width: 680px; margin: 0; color: var(--muted); font: 17px/1.8 var(--zh); }
.hero-actions { display: flex; gap: 10px; flex-wrap: wrap; margin-top: 32px; }
.primary-button, .secondary-button { min-height: 46px; display: inline-flex; align-items: center; justify-content: center; padding: 0 19px; border-radius: 2px; font: 700 13px/1 var(--zh); text-decoration: none; cursor: pointer; }
.primary-button { border: 1px solid var(--accent); background: var(--accent); color: white; }
.primary-button:hover { background: var(--accent-dark); }
.secondary-button { border: 1px solid var(--line); background: var(--panel); }
.drop-zone {
  width: 100%; aspect-ratio: 4 / 5;
  max-height: 470px;
  border: 1px solid var(--line);
  background: var(--panel);
  cursor: pointer;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 11px;
  position: relative;
  box-shadow: var(--shadow);
  transition: transform .2s, border-color .2s, background .2s;
}
.drop-zone::before { content: ""; position: absolute; inset: 12px; border: 1px dashed var(--line); }
.drop-zone:hover, .drop-zone.is-dragging { transform: translateY(-6px) rotate(.25deg); border-color: var(--accent); background: color-mix(in srgb, var(--panel) 86%, var(--accent) 14%); }
.drop-zone .drop-glyph { width: 56px; height: 56px; display: grid; place-items: center; border-radius: 50%; border: 1px solid var(--accent); color: var(--accent); font: 300 27px/1 var(--sans); }
.drop-zone strong { font: 500 30px/1.1 var(--display); }
.drop-zone small { color: var(--muted); font: 12px/1 var(--sans); }
.drop-zone i { position: absolute; left: 24px; bottom: 23px; color: var(--accent); font: 700 9px/1 var(--sans); letter-spacing: .12em; text-transform: uppercase; }
.library-section { max-width: 1280px; margin: 0 auto; padding: 90px clamp(22px, 5vw, 70px) 100px; }
.section-head { display: flex; align-items: end; justify-content: space-between; gap: 30px; margin-bottom: 38px; }
.section-head h2 { margin: 10px 0 0; font: 500 48px/1 var(--display); }
.library-stats { display: flex; gap: 25px; color: var(--muted); font: 11px/1.2 var(--sans); }
.library-stats b { color: var(--ink); font-size: 17px; }
.book-grid { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 28px; }
.book-card { min-width: 0; }
.book-open { display: block; width: 100%; aspect-ratio: .72; padding: 0; border: 0; background: var(--paper-deep); overflow: hidden; cursor: pointer; box-shadow: 0 15px 45px rgba(58, 40, 22, .13); transition: transform .2s, box-shadow .2s; }
.book-open:hover { transform: translateY(-6px); box-shadow: 0 22px 55px rgba(58, 40, 22, .2); }
.book-open img { width: 100%; height: 100%; object-fit: cover; display: block; }
.generated-cover { width: 100%; height: 100%; display: grid; place-items: center; color: var(--paper); background: linear-gradient(150deg, var(--accent-dark), #291e18); }
.generated-cover span { font: 500 86px/1 var(--display); }
.book-card-copy { padding-top: 17px; }
.book-card-copy > small { color: var(--accent); font: 700 9px/1 var(--sans); letter-spacing: .1em; text-transform: uppercase; }
.book-card-copy h3 { margin: 8px 0 5px; min-height: 2.4em; font: 600 20px/1.2 var(--display); display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden; }
.book-card-copy p { margin: 0 0 15px; color: var(--muted); font: 12px/1.4 var(--zh); white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.book-progress { height: 2px; background: var(--line); }
.book-progress i { display: block; height: 100%; background: var(--accent); }
.book-meta { display: flex; justify-content: space-between; margin-top: 8px; color: var(--muted); font: 10px/1 var(--sans); }
.empty-library { min-height: 260px; display: grid; place-items: center; align-content: center; border: 1px dashed var(--line); text-align: center; }
.empty-library span { font: 500 30px/1.2 var(--display); }
.empty-library p { max-width: 480px; color: var(--muted); font-size: 14px; }
.text-button { border: 0; background: transparent; color: var(--accent); cursor: pointer; font-weight: 700; }
.principles { max-width: 1280px; margin: 0 auto 120px; padding: 0 clamp(22px, 5vw, 70px); display: grid; grid-template-columns: repeat(3, 1fr); }
.principles article { padding: 28px; border: 1px solid var(--line); border-right: 0; }
.principles article:last-child { border-right: 1px solid var(--line); }
.principles span { color: var(--accent); font: 700 10px/1 var(--sans); }
.principles h3 { margin: 30px 0 7px; font: 500 25px/1.1 var(--display); }
.principles p { margin: 0; color: var(--muted); font-size: 13px; line-height: 1.65; }
.processing { position: fixed; inset: 0; z-index: 300; display: grid; place-items: center; padding: 24px; background: color-mix(in srgb, var(--paper) 86%, transparent); backdrop-filter: blur(24px); }
.processing-card { width: min(590px, 100%); padding: 48px; border: 1px solid var(--line); background: var(--paper); box-shadow: var(--shadow); }
.processing-mark { display: flex; gap: 6px; margin-bottom: 55px; }
.processing-mark span { width: 12px; height: 42px; background: var(--accent); animation: pulse 1.1s ease-in-out infinite alternate; transform-origin: bottom; }
.processing-mark span:nth-child(2) { animation-delay: .18s; }
.processing-mark span:nth-child(3) { animation-delay: .36s; }
@keyframes pulse { to { transform: scaleY(.35); opacity: .35; } }
.processing-card h2 { margin: 14px 0 10px; font: 500 45px/1 var(--display); }
.processing-card > p:not(.kicker) { min-height: 1.7em; color: var(--muted); }
.processing-track { margin-top: 35px; height: 3px; background: var(--line); }
.processing-track i { display: block; width: 0; height: 100%; background: var(--accent); transition: width .2s; }
.processing-meta { display: flex; justify-content: space-between; margin-top: 10px; color: var(--muted); font: 10px/1.4 var(--sans); }
.processing-meta span:first-child { color: var(--accent); font-weight: 800; }
.toast { position: fixed; left: 50%; bottom: 28px; z-index: 400; transform: translateX(-50%); max-width: min(520px, calc(100vw - 32px)); padding: 12px 18px; color: white; background: #22201c; box-shadow: var(--shadow); font: 13px/1.45 var(--zh); text-align: center; }

/* Reader */
.reader-view { display: grid; grid-template-columns: 292px minmax(0, 1fr); min-height: calc(100vh - 68px); }
.reader-sidebar { position: sticky; top: 68px; height: calc(100vh - 68px); padding: 31px 20px; border-right: 1px solid var(--line); background: color-mix(in srgb, var(--paper) 90%, transparent); overflow: auto; }
.reader-book-title { padding: 0 9px 22px; border-bottom: 1px solid var(--line); }
.reader-book-title small { color: var(--accent); font: 700 9px/1 var(--sans); letter-spacing: .12em; }
.reader-book-title h2 { margin: 9px 0 4px; font: 600 20px/1.15 var(--display); }
.reader-book-title p { margin: 0; color: var(--muted); font-size: 11px; }
.reader-sidebar nav { padding-top: 13px; }
.reader-sidebar nav a { display: grid; grid-template-columns: 25px 1fr auto; gap: 8px; align-items: baseline; padding: 8px 9px; border-left: 2px solid transparent; text-decoration: none; }
.reader-sidebar nav a:hover { background: var(--panel); }
.reader-sidebar nav a.active { color: var(--accent); border-left-color: var(--accent); background: var(--panel); }
.reader-sidebar nav span, .reader-sidebar nav small { color: var(--muted); font: 9px/1 var(--sans); }
.reader-sidebar nav b { font: 500 13px/1.2 var(--display); }
.reader-shell { min-width: 0; }
.reader-tools { position: sticky; top: 68px; z-index: 50; height: 48px; display: flex; align-items: center; justify-content: space-between; padding: 0 26px; border-bottom: 1px solid var(--line); background: color-mix(in srgb, var(--paper) 84%, transparent); backdrop-filter: blur(16px); }
.reader-tools > a { color: var(--muted); text-decoration: none; font: 12px/1 var(--zh); }
.reader-tool-group { display: flex; gap: 3px; }
.reader-tools button { width: 34px; height: 32px; border: 0; background: transparent; cursor: pointer; border-radius: 2px; font: 600 12px/1 var(--sans); }
.reader-tools button:hover { background: var(--panel); }
.mobile-toc { display: none; }
.reading-column { width: min(100%, 790px); margin: 0 auto; padding: 105px 50px 150px; }
.reading-head { margin-bottom: 65px; }
.reading-head h1 { margin: 26px 0 20px; font: 500 clamp(56px, 8vw, 94px)/.9 var(--display); letter-spacing: -.04em; }
.chapter-facts { display: flex; flex-wrap: wrap; gap: 12px 24px; color: var(--muted); font: 11px/1.3 var(--sans); }
.reading-guide { margin-top: 34px; padding: 18px 21px; border-left: 3px solid var(--accent); background: var(--panel); }
.reading-guide b { color: var(--accent); font: 800 10px/1 var(--sans); letter-spacing: .12em; }
.reading-guide p { margin: 8px 0 4px; color: var(--muted); font: 14px/1.7 var(--zh); }
.reading-guide small { color: var(--muted); font: 9px/1 var(--sans); letter-spacing: .08em; }
.reading-body { font: var(--reader-font-size)/var(--reader-leading) var(--serif); letter-spacing: .003em; }
.reading-body p { margin: 0 0 1.08em; hanging-punctuation: first last; }
.reading-body p:first-child::first-letter { float: left; margin: .07em .09em 0 0; color: var(--accent); font: 500 4.5em/.74 var(--display); }
.reading-body p.no-dropcap::first-letter { float: none; margin: 0; color: inherit; font: inherit; }
.reading-body p.attribution { margin: 1.6em 0 2em; color: var(--gold); font: 700 11px/1.4 var(--sans); letter-spacing: .11em; text-transform: uppercase; }
.chapter-footer { margin-top: 90px; padding: 26px 0; border-top: 1px solid var(--line); display: grid; grid-template-columns: 1fr 1fr; gap: 30px; }
.chapter-footer a { text-decoration: none; }
.chapter-footer a.next { text-align: right; }
.chapter-footer small { display: block; margin-bottom: 5px; color: var(--muted); font: 10px/1 var(--sans); text-transform: uppercase; letter-spacing: .12em; }
.chapter-footer b { font: 500 20px/1.2 var(--display); }
.reader-popover { position: fixed; inset: 68px 0 0; z-index: 150; display: grid; place-items: start center; padding: 70px 20px; background: color-mix(in srgb, var(--paper) 77%, transparent); backdrop-filter: blur(18px); }
.search-panel, .menu-panel { width: min(650px, 100%); max-height: calc(100vh - 190px); overflow: auto; padding: 26px; border: 1px solid var(--line); background: var(--paper); box-shadow: var(--shadow); }
.search-panel header, .menu-panel header { display: flex; justify-content: space-between; align-items: center; }
.search-panel h3, .menu-panel h3 { margin: 0; font: 500 31px/1 var(--display); }
.search-panel header button, .menu-panel header button { border: 0; background: transparent; font-size: 24px; cursor: pointer; }
.search-panel input { width: 100%; height: 48px; margin-top: 22px; padding: 0 13px; border: 1px solid var(--line); color: var(--ink); background: var(--panel); }
.search-hint { margin: 8px 0 15px; color: var(--muted); font: 10px/1 var(--sans); }
.search-results a { display: block; padding: 13px 0; border-top: 1px solid var(--line); text-decoration: none; }
.search-results b { display: block; margin-bottom: 4px; color: var(--accent); font: 600 13px/1.2 var(--display); }
.search-results span { color: var(--muted); font: 13px/1.5 var(--serif); }
.no-results { color: var(--muted); text-align: center; padding: 20px; }
.menu-panel > button:not([data-close]) { width: 100%; display: flex; flex-direction: column; gap: 5px; padding: 18px 0; border: 0; border-top: 1px solid var(--line); background: transparent; text-align: left; cursor: pointer; font-weight: 700; }
.menu-panel > button:first-of-type { margin-top: 22px; }
.menu-panel > button span { color: var(--muted); font-size: 11px; font-weight: 400; }
.menu-panel > button.danger { color: #b84335; }

@media (max-width: 1050px) {
  .book-grid { grid-template-columns: repeat(3, minmax(0, 1fr)); }
  .library-hero { grid-template-columns: minmax(360px, 1fr) minmax(270px, 340px); gap: 48px; padding-inline: 40px; }
}

@media (max-width: 820px) {
  .app-bar { grid-template-columns: 1fr auto; }
  .app-bar-center { display: none; }
  .library-hero { grid-template-columns: 1fr; padding: 65px 24px 70px; }
  .drop-zone { width: min(360px, 100%); justify-self: center; }
  .section-head { align-items: start; flex-direction: column; }
  .book-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .principles { grid-template-columns: 1fr; }
  .principles article { border-right: 1px solid var(--line); border-bottom: 0; }
  .principles article:last-child { border-bottom: 1px solid var(--line); }
  .reader-view { grid-template-columns: 1fr; }
  .reader-sidebar { position: fixed; inset: 68px auto 0 0; width: min(330px, 88vw); height: calc(100vh - 68px); transform: translateX(-104%); transition: transform .25s; z-index: 90; box-shadow: var(--shadow); }
  .reader-sidebar { background: var(--paper); }
  .toc-open .reader-sidebar { transform: translateX(0); }
  .reader-tools { top: 68px; padding-inline: 12px; }
  .reader-tools > a { display: none; }
  .mobile-toc { display: inline-grid !important; place-items: center; }
}

@media (max-width: 560px) {
  .app-bar { height: 62px; padding: 0 14px; }
  .wordmark { grid-template-columns: 34px auto; }
  .wordmark-icon { width: 34px; height: 38px; }
  .wordmark small { display: none; }
  .install-button { display: none !important; }
  .quiet-button { padding-inline: 10px; font-size: 11px; }
  .hero-copy h1 { font-size: 49px; }
  .hero-description { font-size: 15px; }
  .library-stats { gap: 15px; }
  .book-grid { gap: 22px 14px; }
  .book-card-copy h3 { font-size: 17px; }
  .book-card-copy p { font-size: 11px; }
  .reader-sidebar { top: 62px; height: calc(100vh - 62px); }
  .reader-tools { top: 62px; }
  .reader-tool-group { gap: 0; }
  .reader-tools button { width: 31px; }
  .reading-column { padding: 76px 21px 110px; }
  .reading-head { margin-bottom: 47px; }
  .reading-head h1 { font-size: 56px; }
  .reading-body { font-size: min(var(--reader-font-size), 22px); }
  .chapter-footer { grid-template-columns: 1fr; }
  .chapter-footer a.next { text-align: left; }
  .reader-popover { inset: 62px 0 0; padding: 24px 12px; }
  .processing-card { padding: 32px 24px; }
  .processing-card h2 { font-size: 37px; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { scroll-behavior: auto !important; animation: none !important; transition: none !important; }
}