:root {
  --reader-font-scale: 1;
  --reader-max-width: 900px;

  --color-background: #f5f5f5;
  --color-surface: #ffffff;
  --color-text: #1a1a1a;
  --color-muted: #5c5c5c;
  --color-border: #cccccc;
  --color-accent: #164a7b;
  --color-accent-text: #ffffff;
  --color-focus: #ff8c00;

  --page-padding: clamp(1rem, 4vw, 3rem);
  --base-font-size: 1.125rem;
  --line-height: 1.65;

  --shadow: 0 2px 12px rgba(0, 0, 0, 0.08);
  --radius: 0.75rem;
}

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

html {
  min-height: 100%;
  background: var(--color-background);
  color: var(--color-text);
  
  /* DEPSreader керує переходами між сторінками сам */
  scroll-behavior: auto;
}

body {
  min-width: 280px;
  min-height: 100vh;
  margin: 0;
  background: var(--color-background);
  color: var(--color-text);
  font-family:
    system-ui,
    -apple-system,
    BlinkMacSystemFont,
    "Segoe UI",
    "Noto Sans",
    Arial,
    sans-serif;
}

button,
a,
input,
select,
textarea {
  font: inherit;
}

button {
  cursor: pointer;
}

button:disabled {
  cursor: not-allowed;
  opacity: 0.5;
}

button:focus-visible,
a:focus-visible,
[tabindex]:focus-visible {
  outline: 3px solid var(--color-focus);
  outline-offset: 3px;
}

.skip-link {
  position: fixed;
  top: 0;
  left: 0;
  z-index: 1000;
  padding: 0.75rem 1rem;
  background: var(--color-accent);
  color: var(--color-accent-text);
  text-decoration: none;
  transform: translateY(-150%);
}

.skip-link:focus {
  transform: translateY(0);
}

.reader-app {
  width: 100%;
  max-width: 100%;

  height: 100vh;
  height: 100dvh;

  min-height: 0;

  display: flex;
  flex-direction: column;

  overflow: hidden;
}

.reader-header {
  position: sticky;
  top: 0;
  z-index: 50;

  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;

  min-height: 4rem;

  padding:
    max(0.5rem, env(safe-area-inset-top))
    max(0.75rem, env(safe-area-inset-right))
    0.5rem
    max(0.75rem, env(safe-area-inset-left));

  background: var(--color-surface);
  border-bottom: 1px solid var(--color-border);
  box-shadow: var(--shadow);

  flex-shrink: 0 0 auto;
}

.reader-brand {
  min-width: 0;
}

.brand-link {
  display: block;
  overflow: hidden;

  color: var(--color-text);
  font-weight: 700;
  text-decoration: none;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.reader-toolbar {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.toolbar-button,
.settings-button,
.navigation-button,
.close-button {
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  background: var(--color-surface);
  color: var(--color-text);
}

.toolbar-button {
  min-height: 2.75rem;
  padding: 0.5rem 0.75rem;

  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.4rem;
}

.toolbar-button:hover,
.settings-button:hover,
.navigation-button:hover {
  border-color: var(--color-accent);
}

.side-panel {
  position: fixed;

  top: 0;
  right: 0;
  bottom: 0;

  z-index: 100;

  width: 28rem;
  max-width: 92vw;

  height: 100vh;
  height: 100dvh;

  overflow-x: hidden;
  overflow-y: auto;

  padding:
    max(1rem, env(safe-area-inset-top))
    max(1rem, env(safe-area-inset-right))
    max(1rem, env(safe-area-inset-bottom))
    max(1rem, env(safe-area-inset-left));

  background: var(--color-surface);
  color: var(--color-text);

  border-left: 1px solid var(--color-border);

  box-shadow: -4px 0 20px rgba(0, 0, 0, 0.15);

  -webkit-overflow-scrolling: touch;
}

.panel-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;

  margin-bottom: 1rem;
}

.panel-header h2 {
  margin: 0;
}

.close-button {
  width: 2.75rem;
  height: 2.75rem;
  font-size: 1.5rem;
  line-height: 1;
}

#toc-list {
  margin: 0;
  padding-left: 1.5rem;
}

#toc-list li {
  margin-bottom: 0.5rem;
}

.toc-button {
  width: 100%;
  padding: 0.75rem;

  text-align: start;

  border: 1px solid var(--color-border);
  border-radius: 0.5rem;

  background: var(--color-surface);
  color: var(--color-text);
}

.toc-button[aria-current="page"] {
  border-color: var(--color-accent);
  background: var(--color-accent);
  color: var(--color-accent-text);
}

.language-list {
  display: grid;
  gap: 0.5rem;
}

.language-button {
  width: 100%;
  min-height: 3rem;
  padding: 0.75rem;

  text-align: start;

  border: 1px solid var(--color-border);
  border-radius: 0.5rem;

  background: var(--color-surface);
  color: var(--color-text);
}

.language-button[aria-current="true"] {
  border-color: var(--color-accent);
  background: var(--color-accent);
  color: var(--color-accent-text);
}

.language-button:disabled {
  opacity: 0.65;
}

.settings-group {
  margin-bottom: 2rem;
}

.settings-group h3 {
  margin-top: 0;
  font-size: 1rem;
}

.settings-actions {
  display: flex;
  gap: 0.5rem;
}

.settings-button {
  min-height: 2.75rem;
  padding: 0.5rem 0.8rem;
}

.settings-wide {
  width: 100%;
}

.settings-button[aria-pressed="true"] {
  background: var(--color-accent);
  color: var(--color-accent-text);
}

.reader-main {
  flex: 1 1 auto;

  width: 100%;
  max-width: 100%;

  min-width: 0;
  min-height: 0;
  height: 0;

  padding: 1rem;

  display: flex;
  flex-direction: column;
  align-items: stretch;
  gap: 0;

  overflow: hidden;
}

.reader-status {
  flex: 0 0 auto;
  width: 100%;
  max-width: var(--reader-max-width);
  margin: 0 auto;
}

.reader-error {
  flex: 0 0 auto;
  width: 100%;
  max-width: var(--reader-max-width);
  margin: 0 auto;
}

.reader-status {
  width: min(var(--reader-max-width), 100%);
  margin: 0 auto 0.75rem;
  color: var(--color-muted);
  text-align: center;
  font-size: 0.95rem;
}

.reader-page {
  width: min(var(--reader-max-width), 100%);
  max-width: 100%;

  min-width: 0;
  min-height: 0;
  height: 100%;

  margin: 0 auto;

  display: flex;
  flex: 1 1 auto;
  flex-direction: column;

  padding: var(--page-padding);

  background: var(--color-surface);
  color: var(--color-text);

  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);

  overflow: hidden;

  touch-action: pan-y;
}

.deps-cover {
  position: relative;
}

.deps-cover-identifier {
  position: absolute;
  top: 0;
  right: 0;

  color: var(--color-muted);
  font-size: 0.85em;
  line-height: 1;
  white-space: nowrap;
}

.deps-work {
  position: relative;
  width: 100%;
  box-sizing: border-box;
}

.deps-work-identifier {
  position: absolute;
  right: 0;
  bottom: 0;

  color: var(--color-muted);
  font-size: 0.85em;
  line-height: 1;
  white-space: nowrap;
}

.page-content {
  width: 100%;
  max-width: 100%;

  margin: 0;

  flex: 1 1 auto;
  min-height: 0;

  overflow-y: auto;
  overflow-x: hidden;

  font-size: calc(var(--base-font-size) * var(--reader-font-scale));
  line-height: var(--line-height);

  -webkit-overflow-scrolling: touch;
}

.page-cover {
  min-height: 100%;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 1rem;

  text-align: center;
}

.page-cover h1 {
  margin: 0;
  font-size: clamp(2rem, 7vw, 4rem);
  line-height: 1.15;
}

.page-cover h2 {
  margin: 0;
  font-size: clamp(1.2rem, 4vw, 2rem);
  font-weight: 500;
}

.page-cover .metadata {
  color: var(--color-muted);
}

.cover-image {
  display: block;
  width: min(100%, 24rem);
  max-height: 50vh;
  object-fit: contain;
  border-radius: 0.5rem;
}

.work-page {
  width: 100%;
}

.work-page h1 {
  margin-top: 0;
  margin-bottom: 1.5rem;

  font-size: clamp(
    1.6rem,
    calc(1.6rem * var(--reader-font-scale)),
    3rem
  );

  line-height: 1.2;
}

.work-author {
  margin-bottom: 1.5rem;
  color: var(--color-muted);
  font-size: 0.95em;
}

.text-block {
  margin: 0 0 1rem;
}

.poem-stanza {
  margin-bottom: 1.5rem;
}

.poem-line {
  display: block;
}

.part-indicator {
  margin-top: 2rem;
  color: var(--color-muted);
  font-size: 0.85em;
  text-align: center;
}

.end-page {
  min-height: 100%;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 1rem;

  text-align: center;
}

.end-page h1 {
  margin: 0;
}

.publication-link {
  display: inline-flex;
  align-items: center;
  justify-content: center;

  min-height: 2.75rem;
  padding: 0.65rem 1rem;

  border: 1px solid var(--color-accent);
  border-radius: var(--radius);

  background: var(--color-accent);
  color: var(--color-accent-text);
  text-decoration: none;
}

.reader-error {
  width: min(var(--reader-max-width), 100%);
  margin: 1rem auto;
  padding: 1rem;

  border: 2px solid currentColor;
  border-radius: var(--radius);
}

.reader-footer {
  flex: 0 0 auto;
  width: 100%;

  padding:
    0.5rem
    max(0.75rem, env(safe-area-inset-right))
    max(0.5rem, env(safe-area-inset-bottom))
    max(0.75rem, env(safe-area-inset-left));

  border-top: 1px solid var(--color-border);
  background: var(--color-surface);

  overflow: hidden;
}

.page-navigation {
  width: min(var(--reader-max-width), 100%);
  max-width: 100%;

  margin: 0 auto;

  display: grid;
  grid-template-columns: 1fr auto 1fr;

  align-items: center;

  gap: 0.5rem;

  min-width: 0;
}

.navigation-button {
  min-height: 2.75rem;
  max-height: 3.25rem;

  padding: 0.5rem 0.75rem;

  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;

  overflow: hidden;
}

#previous-button {
  justify-self: start;
}

#next-button {
  justify-self: end;
}

.page-indicator {
  text-align: center;
  color: var(--color-muted);
  white-space: nowrap;
}

.publication-footer {
  width: min(var(--reader-max-width), 100%);
  margin: 0.75rem auto 0;

  color: var(--color-muted);
  font-size: 0.85rem;
  text-align: center;
}

/* High contrast mode */
body.high-contrast {
  --color-background: #000000;
  --color-surface: #000000;
  --color-text: #ffffff;
  --color-muted: #ffffff;
  --color-border: #ffffff;
  --color-accent: #ffff00;
  --color-accent-text: #000000;
  --color-focus: #00ffff;

  --shadow: none;
}

body.high-contrast .reader-page,
body.high-contrast .reader-header,
body.high-contrast .reader-footer,
body.high-contrast .side-panel,
body.high-contrast button,
body.high-contrast .toc-button,
body.high-contrast .language-button {
  box-shadow: none;
}

/* Reduced motion */
body.reduced-motion *,
body.reduced-motion *::before,
body.reduced-motion *::after {
  scroll-behavior: auto !important;
  transition: none !important;
  animation: none !important;
}

/* RTL */
.reader-app[dir="rtl"] .side-panel {
  right: auto;
  left: 0;
  border-left: 0;
  border-right: 1px solid var(--color-border);
}

.reader-app[dir="rtl"] #toc-list {
  padding-left: 0;
  padding-right: 1.5rem;
}

.reader-app[dir="rtl"] .reader-page,
.reader-app[dir="rtl"] .page-content {
  text-align: start;
}

/* Japanese */
.reader-app[lang="ja"] .page-content {
  line-height: 1.9;
  font-family:
    "Noto Sans JP",
    "Yu Gothic",
    "Hiragino Kaku Gothic ProN",
    system-ui,
    sans-serif;
}

/* Mobile */
@media (max-width: 700px) {
  .reader-header {
    align-items: center;
    flex-direction: row;
    flex-wrap: wrap;
    gap: 0.5rem;
  }

  .reader-brand {
    flex: 1 1 auto;
    min-width: 0;
  }

  .reader-toolbar {
    flex: 0 1 auto;

    display: grid;
    grid-template-columns: repeat(3, auto);

    gap: 0.35rem;
  }

  .toolbar-button {
    width: auto;
    min-width: 2.75rem;
    min-height: 2.5rem;
    padding: 0.45rem 0.55rem;
  }

  .reader-main {
    flex: 1 1 auto;

    width: 100%;
    min-width: 0;
    min-height: 0;
    height: 0;

    padding: 0.5rem;

    display: flex;
    flex-direction: column;
    overflow: hidden;
  }

  .reader-page {
    flex: 1 1 auto;

    width: 100%;
    max-width: 100%;

    min-width: 0;
    min-height: 0;
    height: 100%;

    padding: 1rem;

    border-radius: 0.5rem;

    display: flex;
    flex-direction: column;

    overflow: hidden;
  }

  .page-content {
    flex: 1 1 auto;

    width: 100%;
    min-width: 0;
    min-height: 0;

    overflow-x: hidden;
    overflow-y: auto;

    font-size:
      calc(1.05rem * var(--reader-font-scale));
  }

  .reader-footer {
    flex: 0 0 auto;

    width: 100%;
    min-height: 0;

    padding:
      0.4rem
      max(0.5rem, env(safe-area-inset-right))
      max(0.4rem, env(safe-area-inset-bottom))
      max(0.5rem, env(safe-area-inset-left));

    overflow: hidden;
  }

  .page-navigation {
    width: 100%;
    max-width: 100%;

    display: grid;
    grid-template-columns: 1fr 1fr;

    gap: 0.4rem;
  }

  .page-indicator {
    grid-column: 1 / -1;
    grid-row: 1;

    min-height: 1.5rem;

    overflow: hidden;
    white-space: nowrap;
    text-overflow: ellipsis;
  }

  #previous-button,
  #next-button {
    grid-row: 2;

    width: 100%;
    min-width: 0;
    min-height: 2.75rem;
    max-height: 3rem;

    padding: 0.45rem 0.5rem;

    overflow: hidden;
  }
}

@media (max-width: 420px) {
  .reader-header {
    padding:
      0.4rem
      0.5rem;
  }

  .brand-link {
    font-size: 0.9rem;
  }

  .toolbar-button {
    min-height: 2.5rem;
    min-width: 2.5rem;
    padding: 0.4rem;
  }

  .toolbar-button span:last-child {
    font-size: 0.8rem;
  }

  .reader-page {
    padding: 0.75rem;
  }

  .page-content {
    font-size:
      calc(1rem * var(--reader-font-scale));
  }

  .navigation-button {
    min-height: 2.75rem;
    padding: 0.55rem 0.65rem;
  }
}

@media (min-width: 1200px) and (min-height: 600px) {
  .reader-main {
    padding: 1.25rem;
  }

  .reader-page {
    min-height: 0;
  }

  .page-content {
    font-size:
      calc(var(--base-font-size) * var(--reader-font-scale));
  }
}

/* Print */
@media print {
  .reader-header,
  .reader-footer,
  .side-panel,
  .reader-status,
  .skip-link {
    display: none !important;
  }

  body,
  .reader-app,
  .reader-main,
  .reader-page {
    background: #fff;
    color: #000;
  }

  .reader-page {
    border: 0;
    box-shadow: none;
    width: 100%;
    min-height: auto;
  }
}

#publication-footer {
  max-height: 0;
  overflow: hidden;
}