/* ==========================================================================
   Lerngesellschaft — Bradford LL on the open page

   Pure white. Bradford roman title. Two precise color accents:
   fountain-pen blue (#1a3a5e) for structure, parchment yellow (#fcf2c6)
   for selection. Three motion gestures (no title animation): cover-mark
   draws in, sidenote hairline binds on hover, section numeral pulses on
   scroll-arrival.

   Layout is fluid via clamp() — no breakpoint snapping for type and
   spacing. The 900px breakpoint is reserved only for the sidenote layout
   switch (margin → inline-expandable).
   ========================================================================== */

@font-face {
  font-family: "BradfordLLWeb-Book";
  font-style: normal;
  font-weight: normal;
  font-display: swap;
  src: url("/fonts/BradfordLLWeb-Book.woff2") format("woff2"),
       url("/fonts/BradfordLLWeb-Book.woff") format("woff");
}

@font-face {
  font-family: "BradfordLLWeb-Book";
  font-style: italic;
  font-weight: normal;
  font-display: swap;
  src: url("/fonts/BradfordLLWeb-BookItalic.woff2") format("woff2"),
       url("/fonts/BradfordLLWeb-BookItalic.woff") format("woff");
}

/* --------------------------------------------------------------------------
   Tokens — fluid across viewport widths
   -------------------------------------------------------------------------- */

:root {
  --serif: "BradfordLLWeb-Book", "Iowan Old Style", Georgia, serif;

  --paper: #ffffff;
  --ink:   #050505;
  --ink-soft:  #5d574e;
  --ink-faint: #7a7268;     /* WCAG AA: 4.7:1 against white */
  --rule:  rgba(5, 5, 5, 0.10);

  --accent:        #1a3a5e;     /* fountain-pen blue: structure markers — section numerals, hairline bind, link hover */
  --accent-bright: #2a52a3;     /* brighter blue (legacy, currently unused outside fallback) */
  --accent-warm:   #9a3a14;     /* burnt sienna: cover mark, pulse highlight — the warm counterpoint */
  --highlight:     #fcf2c6;     /* parchment yellow: selection only */

  --measure: 30em;
  --gutter:  2.4em;
  --sidenote-width: 13em;

  /* Fluid sizing — minimum (small phones) → maximum (large desktops) */
  --pad-top:    clamp(3em,    1em + 11vw, 9.5em);
  --pad-side:   clamp(1em,    0.6em + 1.4vw, 1.5em);
  --pad-bottom: clamp(3em,    1em + 4vw, 6em);

  --title-size: 3.15rem;
  --subtitle-size: 1rem;

  --leading: 1.55;
  --motion:  cubic-bezier(0.22, 1, 0.36, 1);
}

/* --------------------------------------------------------------------------
   Reset + base
   -------------------------------------------------------------------------- */

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

html {
  font-size: 19px;
  text-size-adjust: 100%;
  -webkit-text-size-adjust: 100%;
}

@media (max-width: 480px) {
  html { font-size: 17px; }
  :root { --title-size: 2.05rem; }
}

html { background: var(--paper); overflow-x: hidden; }

body {
  margin: 0;
  background: transparent;
  color: var(--ink);
  font-family: var(--serif);
  font-size: 1rem;
  line-height: var(--leading);
  font-feature-settings: "kern", "liga", "onum", "calt";
  font-variant-numeric: oldstyle-nums;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  min-height: 100vh;
  overflow-wrap: break-word;
  /* Respect notch / safe-area on iOS */
  padding-left: env(safe-area-inset-left, 0);
  padding-right: env(safe-area-inset-right, 0);
}

/* --------------------------------------------------------------------------
   Background neural-network canvas — fixed behind everything.
   The animation is generated outside the main reading measure, so it reads
   as margin atmosphere rather than a texture behind the prose.
   -------------------------------------------------------------------------- */

.network-bg {
  position: fixed !important;
  top: 0 !important;
  left: 0 !important;
  width: 100vw !important;
  height: 100vh !important;
  z-index: 0;
  pointer-events: none;
  display: block !important;
}

@media (max-width: 700px) {
  .network-bg { display: none !important; }
}

a {
  color: inherit;
  text-decoration: underline;
  text-decoration-thickness: from-font;
  text-decoration-color: var(--rule);
  text-underline-offset: 0.18em;
  transition: color 220ms var(--motion),
              text-decoration-color 220ms var(--motion),
              border-color 220ms var(--motion);
}
a:hover {
  color: var(--accent);
  text-decoration-color: var(--accent);
}

::selection      { background: var(--highlight); color: var(--ink); }
::-moz-selection { background: var(--highlight); color: var(--ink); }

.skip { position: absolute; left: -9999px; }
.skip:focus {
  position: fixed;
  top: 1em;
  left: 1em;
  background: var(--ink);
  color: var(--paper);
  padding: 0.4em 0.8em;
  z-index: 100;
}

/* --------------------------------------------------------------------------
   Document
   -------------------------------------------------------------------------- */

.document {
  position: relative;
  z-index: 1;
  background: transparent;
  max-width: calc(var(--measure) + var(--gutter) + var(--sidenote-width));
  margin: 0 auto;
  padding: var(--pad-top) var(--pad-side) var(--pad-bottom);
  counter-reset: section;
}

.document > * { max-width: var(--measure); }

/* --------------------------------------------------------------------------
   Cover
   -------------------------------------------------------------------------- */

.cover {
  margin: 0;
  padding: 0;
  max-width: var(--measure);
}

.cover-title {
  font-style: normal;
  font-size: var(--title-size);
  line-height: 1.0;
  margin: 0;
  font-weight: normal;
  letter-spacing: 0;
  hanging-punctuation: first last;
}

.cover-mark {
  width: clamp(24px, 1.6em, 32px);
  height: 3px;
  background: var(--accent-warm);
  margin: 1.6em 0 1.4em;
  transform-origin: left center;
  transform: scaleX(0);
  transition: transform 720ms var(--motion);
}
body.is-loaded .cover-mark {
  transform: scaleX(1);
  transition-delay: 200ms;
}

.cover-subtitle,
.cover-byline,
.cover-altlang { text-indent: 0; }

.cover-subtitle {
  font-style: normal;
  font-size: var(--subtitle-size);
  line-height: 1.5;
  color: var(--ink-soft);
  margin: 0;
  max-width: 24em;
  opacity: 0;
  transition: opacity 720ms var(--motion);
}
body.is-loaded .cover-subtitle {
  opacity: 1;
  transition-delay: 360ms;
}

.cover-byline {
  font-style: italic;
  font-size: 0.86rem;
  color: var(--ink-soft);
  margin: 4em 0 0;
  letter-spacing: 0;
  opacity: 0;
  transition: opacity 720ms var(--motion);
}
body.is-loaded .cover-byline {
  opacity: 1;
  transition-delay: 540ms;
}

.cover-altlang {
  font-style: italic;
  font-size: 0.78rem;
  margin: 0.5em 0 0;
  opacity: 0;
  transition: opacity 720ms var(--motion);
}
body.is-loaded .cover-altlang {
  opacity: 1;
  transition-delay: 680ms;
}
.cover-altlang a {
  color: var(--ink-faint);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  padding-bottom: 0.05em;
  transition: color 220ms var(--motion), border-color 220ms var(--motion);
}
.cover-altlang a:hover {
  color: var(--accent);
  border-bottom-color: var(--accent);
}

/* --------------------------------------------------------------------------
   Body — justified, hyphens, indented continuation paragraphs.
   :where() flattens the specificity so cover-class margins win.
   -------------------------------------------------------------------------- */

.cover + p {
  margin-top: clamp(3.5em, 6em, 6em);
}

:where(.document) p,
:where(.document) ul,
:where(.document) ol {
  margin: 0;
  text-align: justify;
  hyphens: auto;
  -webkit-hyphens: auto;
  hyphenate-limit-chars: 7 3 3;
  word-spacing: -0.015em;
  text-justify: inter-word;
  hanging-punctuation: first last;
}

:where(.document) p + p { text-indent: 1.2em; }

.document hr { display: none; }

/* --------------------------------------------------------------------------
   Section headings — italic title + lower-roman numeral in fountain-pen blue
   -------------------------------------------------------------------------- */

.document h2 {
  counter-increment: section;
  font-weight: normal;
  font-style: italic;
  font-size: 1.18rem;
  text-align: left;
  margin: clamp(3.5em, 5.5em, 5.5em) 0 1.6em;
  line-height: 1.32;
  hyphens: none;
}
.document h2::before {
  content: counter(section, lower-roman);
  display: block;
  font-style: italic;
  font-size: 0.8rem;
  color: var(--accent);
  margin-bottom: 0.45em;
  letter-spacing: 0;
  transition: color 200ms var(--motion);
}
.document h2.is-arrived::before {
  animation: numeral-pulse 1200ms var(--motion);
}

@keyframes numeral-pulse {
  0%   { color: var(--accent); }
  20%  { color: var(--accent-warm); }
  100% { color: var(--accent); }
}

.document h3 {
  font-weight: normal;
  font-style: italic;
  font-size: 1rem;
  margin: 2.4em 0 0.6em;
  text-align: left;
}

.document blockquote {
  font-style: italic;
  margin: 2em 0 2em 1.6em;
  padding: 0;
  border: none;
  color: var(--ink);
  max-width: calc(var(--measure) - 3.2em);
  hyphens: auto;
  -webkit-hyphens: auto;
  text-align: left;
}
.document blockquote p { text-indent: 0; text-align: left; }
.document blockquote p + p { text-indent: 1.2em; }

.document ul, .document ol { padding-left: 1.4em; margin: 1em 0; }
.document li { margin: 0.3em 0; text-align: left; }
.document li > p { text-indent: 0; text-align: left; }

.document em, .document i, .document cite { font-style: italic; }
.document strong, .document b { font-style: italic; font-weight: normal; }

.document q { quotes: "“" "”" "‘" "’"; }
.document[lang="de"] q,
.document :lang(de) q { quotes: "»" "«" "›" "‹"; }

/* --------------------------------------------------------------------------
   Sidenotes — JS line-aligned on wide screens; inline expandable on narrow
   -------------------------------------------------------------------------- */

.note { display: inline; }

.note-marker {
  display: inline;
  cursor: pointer;
  position: relative;
  font-style: italic;
  font-size: 0.78em;
  vertical-align: super;
  line-height: 0;
  margin: 0 0.04em;
  color: var(--ink-soft);
  user-select: none;
  transition: color 160ms var(--motion);
  text-decoration: none;
}
.note-marker sup { font-size: inherit; vertical-align: baseline; }
.note-marker:hover,
.note-marker:focus-visible {
  color: var(--accent);
  outline: none;
}

.sidenote {
  position: absolute;
  right: 0;
  width: var(--sidenote-width);
  top: 0;
  font-style: italic;
  font-size: 0.78rem;
  line-height: 1.42;
  color: var(--ink-soft);
  text-align: left;
  text-indent: 0;
  hyphens: none;

  opacity: 0;
  transform: translateY(4px);
  transition: opacity 480ms var(--motion),
              transform 480ms var(--motion),
              color 220ms var(--motion);
}
.sidenote.is-revealed { opacity: 1; transform: translateY(0); }
.sidenote.is-active   { color: var(--ink); }

.sidenote-num {
  font-style: italic;
  font-size: 0.85em;
  color: var(--ink-faint);
  margin-right: 0.4em;
  transition: color 220ms var(--motion);
}
.sidenote.is-active .sidenote-num { color: var(--accent); }

.sidenote-overlay {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  overflow: visible;
  z-index: 1;
}
.sidenote-overlay .hairline {
  fill: none;
  stroke: var(--accent);
  stroke-width: 0.85;
  opacity: 0.65;
  vector-effect: non-scaling-stroke;
}

.footnotes-print { display: none; }

/* --------------------------------------------------------------------------
   Colophon
   -------------------------------------------------------------------------- */

.colophon {
  max-width: var(--measure);
  margin: clamp(5em, 9em, 9em) 0 0;
  padding: 2em 0 0;
  font-style: italic;
  font-size: 0.82rem;
  color: var(--ink-soft);
  line-height: 1.7;
  border-top: 1px solid var(--rule);
}
.colophon p { margin: 0; text-align: left; text-indent: 0; }
.colophon-alt {
  font-size: 0.78rem;
  color: var(--ink-faint);
  margin-top: 0.2em;
}
.colophon a {
  color: inherit;
  text-decoration: none;
  border-bottom: 1px solid var(--rule);
  padding-bottom: 0.05em;
  transition: color 220ms var(--motion), border-color 220ms var(--motion);
}
.colophon a:hover {
  color: var(--accent);
  border-bottom-color: var(--accent);
}

/* --------------------------------------------------------------------------
   Below 900px: sidenotes collapse to inline expandable
   -------------------------------------------------------------------------- */

@media (max-width: 900px) {
  :root { --sidenote-width: auto; }

  .document {
    max-width: var(--measure);
    background: transparent;
  }
  .document p { text-align: left; word-spacing: 0; }

  /* Larger tap target around the marker without affecting visual layout */
  .note-marker {
    padding: 0.5em 0.35em;
    margin: -0.5em -0.35em;
    display: inline-block;
  }
  .note-marker sup {
    vertical-align: 0.45em;
  }

  .sidenote {
    position: relative;
    right: auto;
    top: auto !important;
    width: auto;
    margin: 0;
    padding: 0 0 0 1em;
    border-left: 1px solid var(--rule);
    display: block;
    max-height: 0;
    overflow: hidden;
    opacity: 0;
    transform: none;
    transition: max-height 320ms var(--motion),
                opacity 280ms var(--motion),
                margin 280ms var(--motion),
                padding 280ms var(--motion);
    pointer-events: none;
    font-size: 0.86rem;
  }
  .sidenote.is-expanded {
    max-height: 32em;
    opacity: 1;
    margin: 0.6em 0 0.8em;
    padding: 0.2em 0 0.2em 1em;
    pointer-events: auto;
  }
  .sidenote.is-revealed { transform: none; }

  .note-marker[aria-expanded="true"] { color: var(--accent); }

  .sidenote-overlay { display: none; }
}

/* --------------------------------------------------------------------------
   Below 480px — phone-specific adjustments
   -------------------------------------------------------------------------- */

@media (max-width: 480px) {
  .cover-mark { height: 2px; }
  .cover-byline { margin-top: 3em; }
  .document h2 { font-size: 1.12rem; }
  .colophon { font-size: 0.86rem; }
}

/* --------------------------------------------------------------------------
   Reduced motion
   -------------------------------------------------------------------------- */

@media (prefers-reduced-motion: reduce) {
  .cover-mark,
  .cover-subtitle,
  .cover-byline,
  .cover-altlang,
  .sidenote,
  .note-marker,
  .document h2::before,
  a {
    transition: none !important;
    transition-delay: 0ms !important;
    transform: none !important;
    animation: none !important;
  }
  .cover-subtitle,
  .cover-byline,
  .cover-altlang,
  .sidenote { opacity: 1 !important; }
  .cover-mark { transform: scaleX(1) !important; }
  .sidenote-overlay { display: none; }
}

/* --------------------------------------------------------------------------
   Print
   -------------------------------------------------------------------------- */

@media print {
  :root {
    --paper: #fff;
    --ink: #000;
    --ink-soft: #333;
    --ink-faint: #777;
    --accent: #000;
    --rule: rgba(0, 0, 0, 0.2);
  }
  @page { size: A5; margin: 22mm 18mm 24mm 22mm; }
  body { background: #fff; padding: 0; }
  .skip { display: none; }
  .network-bg { display: none !important; }
  .document { padding: 0; max-width: none; }
  .document > * { max-width: none; }
  .cover-mark { display: none; }
  .cover { padding: 4em 0 0; page-break-after: always; }
  .cover-title { font-size: 2.4rem; }
  .cover-subtitle, .cover-byline { opacity: 1; }
  .cover-altlang, .sidenote-overlay { display: none; }
  .document h2 { page-break-after: avoid; }
  .document p, .document blockquote { orphans: 3; widows: 3; }
  .sidenote {
    position: static;
    float: footnote;
    width: auto;
    margin: 0;
    padding: 0;
    font-size: 9pt;
    color: #000;
    opacity: 1;
    transform: none;
  }
  .footnotes-print {
    display: block;
    margin-top: 4em;
    padding-top: 1em;
    border-top: 1px solid var(--rule);
    font-size: 9pt;
  }
  .colophon { page-break-before: always; border-top: none; }
  .colophon-alt { display: none; }
  a { text-decoration: none; color: inherit; }
}