:root{
  --paper: #fbfaf6;
  --ink: #121212;
  --muted: #5b5b5b;
  --rule: rgba(18,18,18,.12);

  --max: 980px;
  --baseline: 8px;

  --pad-m: 20px;
  --pad-t: 48px;
  --pad-d: 64px;

  --gutter-m: 16px;
  --gutter-t: 20px;
  --gutter-d: 24px;

  --radius: 10px;
}

/* Reset minimal */
*{ box-sizing:border-box; }
html,body{ height:100%; }
body{
  margin:0;
  background: var(--paper);
  color: var(--ink);
  font-family: ui-sans-serif, system-ui, -apple-system, Segoe UI, Roboto, Helvetica, Arial, "Apple Color Emoji","Segoe UI Emoji";
  letter-spacing: .01em;
}

/* Header */
.site-header{
  position: sticky;
  top: 0;
  z-index: 10;
  background: color-mix(in srgb, var(--paper) 92%, white 8%);
  border-bottom: 1px solid var(--rule);
}
.nav{
  max-width: var(--max);
  margin: 0 auto;
  padding: calc(var(--baseline)*2) var(--pad-m);
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap: var(--gutter-m);
}
.brand{
  text-decoration:none;
  color: var(--ink);
  font-weight: 600;
}
.nav-links a{
  text-decoration:none;
  color: var(--muted);
  margin-left: calc(var(--baseline)*3);
}
.nav-links a:hover{ color: var(--ink); }

/* Book container */
.book{
  max-width: var(--max);
  margin: 0 auto;
  padding: 0 var(--pad-m) calc(var(--baseline)*14);
}

/* Page = "Buchseite" */
.page{
  margin: calc(var(--baseline)*10) 0;
  padding: 0;
}
.page__inner{
  /* Satzspiegel (ruhig, konstant) */
  padding: var(--pad-m);
  border: 1px solid var(--rule);
  border-radius: var(--radius);
  background: color-mix(in srgb, var(--paper) 92%, white 8%);
}

/* Baseline rhythm helpers */
.rule{
  height:1px;
  background: var(--rule);
  margin: calc(var(--baseline)*4) 0;
}

/* Grid system: 12 columns desktop, 8 tablet, 4 mobile */
.grid{
  display:grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--gutter-m);
  align-items:start;
}

/* Column spans (mobile default: 4 columns) */
.col-12{ grid-column: 1 / -1; }
.col-8{ grid-column: 1 / -1; }
.col-7{ grid-column: 1 / -1; }
.col-6{ grid-column: 1 / -1; }
.col-5{ grid-column: 1 / -1; }
.col-4{ grid-column: 1 / -1; }

/* Tablet */
@media (min-width: 768px){
  .book{ padding: 0 var(--pad-t) calc(var(--baseline)*16); }
  .nav{ padding-left: var(--pad-t); padding-right: var(--pad-t); }
  .page__inner{ padding: var(--pad-t); }

  .grid{ grid-template-columns: repeat(8, 1fr); gap: var(--gutter-t); }
  .col-12{ grid-column: 1 / -1; }
  .col-8{ grid-column: 1 / span 8; }
  .col-7{ grid-column: 1 / span 7; }
  .col-6{ grid-column: 1 / span 4; }
  .col-5{ grid-column: 1 / span 5; }
  .col-4{ grid-column: 1 / span 4; }
}

/* Desktop */
@media (min-width: 1024px){
  .book{ padding: 0 var(--pad-d) calc(var(--baseline)*18); }
  .nav{ padding-left: var(--pad-d); padding-right: var(--pad-d); }
  .page__inner{ padding: var(--pad-d); }

  .grid{ grid-template-columns: repeat(12, 1fr); gap: var(--gutter-d); }
  .col-12{ grid-column: 1 / -1; }
  .col-8{ grid-column: 1 / span 8; }
  .col-7{ grid-column: 1 / span 7; }
  .col-6{ grid-column: auto / span 6; }
  .col-5{ grid-column: auto / span 5; }
  .col-4{ grid-column: auto / span 4; }
}

/* Typo */
.h1{
  font-size: clamp(30px, 3vw, 40px);
  line-height: 1.15;
  margin: 0 0 calc(var(--baseline)*3) 0;
}
.lead{
  font-size: 17px;
  line-height: 1.7;
  color: var(--muted);
  margin: 0;
  max-width: 68ch;
}
.body{
  font-size: 15px;
  line-height: 1.8;
  color: var(--ink);
  margin: 0 0 calc(var(--baseline)*3) 0;
  max-width: 70ch;
}
.kicker{
  text-transform: uppercase;
  letter-spacing: .12em;
  font-size: 11px;
  color: var(--muted);
  margin: 0 0 calc(var(--baseline)*2) 0;
}
.quote{
  font-size: 20px;
  line-height: 1.6;
  margin: 0 0 calc(var(--baseline)*3) 0;
  max-width: 55ch;
}

/* Figures */
.figure{ margin:0; }
.img{
  width:100%;
  height:auto;
  display:block;
  border-radius: 8px;
  background: rgba(18,18,18,.04);
}

/* Caption / Meta */
.caption{
  display:flex;
  gap: calc(var(--baseline)*2);
  align-items: baseline;
  justify-content: flex-start;
  flex-wrap: wrap;
  margin-top: calc(var(--baseline)*2);
}
.caption__title{
  font-size: 13px;
  color: var(--ink);
}
.meta{
  font-size: 11.5px;
  color: var(--muted);
  letter-spacing: .02em;
}
.meta--stack{
  margin-top: calc(var(--baseline)*2);
  font-size: 12px;
  line-height: 1.6;
}
.info{
  margin-left: auto;
  border: none;
  background: transparent;
  color: var(--muted);
  font-size: 12px;
  padding: calc(var(--baseline)*1) calc(var(--baseline)*2);
  cursor: pointer;
}
.info:hover{ color: var(--ink); }
.info:focus-visible{
  outline: 2px solid var(--ink);
  outline-offset: 2px;
}
.info--block{ margin-left: 0; padding-left: 0; }

/* Notes */
.note{
  margin-top: calc(var(--baseline)*2);
  padding-top: calc(var(--baseline)*2);
  border-top: 1px solid var(--rule);
  font-size: 14px;
  line-height: 1.8;
  color: var(--ink);
  max-width: 70ch;
}
.note--block{
  border-top: 1px solid var(--rule);
  padding-top: calc(var(--baseline)*2);
}

/* Templates */
.page--full .img{
  /* Full, aber buchig: kein randloser Screen-Fill */
  max-height: 72vh;
  object-fit: contain;
}

.page--spread .figure{ align-self:start; }

.page--block .text{
  padding-top: calc(var(--baseline)*1);
}

.page--textled .figure{
  align-self: end;
}

.page--pause .page__inner{
  padding-top: calc(var(--baseline)*16);
  padding-bottom: calc(var(--baseline)*16);
}
.pause{
  text-align:center;
  color: var(--muted);
}
.pause__line{
  margin:0 0 calc(var(--baseline)*2) 0;
  letter-spacing: .2em;
}
.pause__text{
  margin:0;
  font-size: 13px;
  letter-spacing: .04em;
}

/* TOC */
.toc{
  list-style:none;
  padding:0;
  margin:0;
  display:grid;
  gap: calc(var(--baseline)*2);
  max-width: 60ch;
}
.toc a{
  color: var(--ink);
  text-decoration:none;
}
.toc a:hover{ text-decoration: underline; }
.toc__meta{
  float:right;
  color: var(--muted);
  font-size: 12px;
}

/* Book nav (fixed, dezent) */
.book-nav{
  position: sticky;
  bottom: 0;
  background: color-mix(in srgb, var(--paper) 92%, white 8%);
  border-top: 1px solid var(--rule);
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap: var(--gutter-m);
  padding: calc(var(--baseline)*2) var(--pad-m);
}
.navbtn{
  border: none;
  background: transparent;
  color: var(--muted);
  font-size: 12px;
  padding: calc(var(--baseline)*1) calc(var(--baseline)*2);
  cursor:pointer;
}
.navbtn:hover{ color: var(--ink); }
.navbtn:disabled{ opacity:.35; cursor: default; }
.navbtn:focus-visible{
  outline: 2px solid var(--ink);
  outline-offset: 2px;
}
.navstat{
  font-size: 12px;
  color: var(--muted);
  text-align:center;
}
.navtitle{
  display:block;
  margin-top: 2px;
  color: var(--ink);
}

/* --- Lightbox (editorial, minimal) --- */
.lightbox {
  position: fixed;
  inset: 0;
  z-index: 999;
  background: rgba(18, 18, 18, 0.92);
  display: none;
  padding: 24px;
}

.lightbox[aria-hidden="false"] {
  display: grid;
  place-items: center;
}

.lightbox__panel {
  width: min(1100px, 100%);
  max-height: 92vh;
  display: grid;
  gap: 12px;
}

.lightbox__img {
  width: 100%;
  max-height: 78vh;
  object-fit: contain;
  border-radius: 10px;
  background: rgba(255,255,255,0.03);
}

.lightbox__meta {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  align-items: baseline;
  color: rgba(255,255,255,0.80);
  font-size: 12px;
}

.lightbox__title {
  color: rgba(255,255,255,0.92);
  font-size: 13px;
}

.lightbox__exif {
  color: rgba(255,255,255,0.70);
}

.lightbox__note {
  color: rgba(255,255,255,0.85);
  font-size: 13px;
  line-height: 1.7;
  max-width: 80ch;
}

.lightbox__top {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.lightbox__close {
  border: none;
  background: transparent;
  color: rgba(255,255,255,0.75);
  font-size: 12px;
  padding: 6px 10px;
  cursor: pointer;
}
.lightbox__close:hover { color: rgba(255,255,255,0.95); }
.lightbox__close:focus-visible {
  outline: 2px solid rgba(255,255,255,0.9);
  outline-offset: 2px;
}