/* Storytelling-Karten. Farben über data-bg / data-card (alle Farben aus dem Theme). */
.stack {
  --stack-bg: var(--pitch-black); --stack-fg: var(--porcelain); --stack-muted: var(--on-dark); --stack-accent: var(--golden-sand);
  --card-bg: var(--evergreen); --card-fg: var(--porcelain); --card-muted: var(--on-dark); --card-accent: var(--golden-sand); --card-line: transparent;
  --strip: 60px;                                   /* sichtbarer Streifen der vorherigen Karte */
  --stack-top: calc(var(--header-h) + var(--space-4));
  padding: var(--section-space) 0;
  background: var(--stack-bg);
  color: var(--stack-fg);
}
/* Hintergrund */
.stack[data-bg="evergreen"]   { --stack-bg: var(--evergreen); }
.stack[data-bg="deep_walnut"] { --stack-bg: var(--deep-walnut); }
.stack[data-bg="porcelain"], .stack[data-bg="white"], .stack[data-bg="golden_sand"] { --stack-fg: var(--pitch-black); --stack-muted: var(--on-light); --stack-accent: var(--evergreen); }
.stack[data-bg="porcelain"]   { --stack-bg: var(--porcelain); }
.stack[data-bg="white"]       { --stack-bg: var(--white); }
.stack[data-bg="golden_sand"] { --stack-bg: var(--golden-sand); --stack-muted: rgba(16, 11, 4, .76); }
/* Karten */
.stack[data-card="pitch_black"] { --card-bg: var(--pitch-black); }
.stack[data-card="deep_walnut"] { --card-bg: var(--deep-walnut); }
.stack[data-card="porcelain"], .stack[data-card="white"], .stack[data-card="golden_sand"] { --card-fg: var(--pitch-black); --card-muted: var(--on-light); --card-accent: var(--evergreen); }
.stack[data-card="porcelain"]   { --card-bg: var(--porcelain); }
.stack[data-card="white"]       { --card-bg: var(--white); }
.stack[data-card="golden_sand"] { --card-bg: var(--golden-sand); --card-muted: rgba(16, 11, 4, .76); }
/* Gleiche Farbe für Karte und Hintergrund: feine Linie, damit die Karten sich abheben */
.stack[data-bg="pitch_black"][data-card="pitch_black"], .stack[data-bg="evergreen"][data-card="evergreen"], .stack[data-bg="deep_walnut"][data-card="deep_walnut"] { --card-line: var(--line-dark-strong); }
.stack[data-bg="porcelain"][data-card="porcelain"], .stack[data-bg="white"][data-card="white"], .stack[data-bg="golden_sand"][data-card="golden_sand"] { --card-line: var(--line-light-strong); }

.stack__grid { display: grid; grid-template-columns: minmax(260px, 1fr) minmax(0, 2fr); gap: var(--gap-columns); align-items: start; }
.stack__rail { position: sticky; top: var(--sticky-top); }
.stack .stack__heading { max-width: 430px; margin: 0; color: var(--stack-fg); }

.stack__list { display: grid; gap: var(--space-7); margin: 0; padding: 0; list-style: none; }
.stack__card {
  position: sticky;
  top: calc(var(--sticky-top) + var(--i) * var(--strip));
  min-height: clamp(280px, 38vh, 360px);
  padding: 20px clamp(24px, 3vw, 48px) clamp(28px, 3vw, 44px);
  border: 1px solid var(--card-line);
  border-radius: var(--radius-sm);
  background: var(--card-bg);
  color: var(--card-fg);
  box-shadow: 0 -12px 32px -18px rgba(16, 11, 4, .55);  /* Kante, wenn die Karte über die vorherige gleitet */
}
.stack .stack__meta { display: flex; align-items: baseline; gap: var(--space-4); min-height: calc(var(--strip) - 20px); margin: 0 0 var(--space-6); }
.stack__num { color: var(--card-accent); font-family: var(--font-display); font-size: 22px; font-style: italic; line-height: 1; }
.stack__topic { color: var(--card-accent); font-size: var(--fs-label); font-weight: var(--fw-bold); letter-spacing: var(--ls-label); text-transform: uppercase; }
.stack .stack__statement { max-width: 22ch; margin: 0; font-family: var(--font-display); font-size: clamp(1.75rem, 1.3rem + 1.9vw, 2.75rem); font-weight: var(--fw-medium); line-height: 1.12; letter-spacing: var(--ls-title); }
.stack .stack__consequence { max-width: 46ch; margin: var(--space-5) 0 0; color: var(--card-muted); font-size: var(--fs-body-lg); line-height: 1.6; }

/* Abschluss */
.stack__closing { max-width: 88ch; margin-top: var(--section-space); }
.stack .stack__closing-label { margin: 0 0 var(--space-4); color: var(--stack-accent); font-size: var(--fs-closing); font-weight: var(--fw-bold); letter-spacing: .12em; line-height: 1.2; text-transform: uppercase; }
.stack__closing-text, .stack .stack__closing-highlight { font-family: var(--font-display); font-size: var(--fs-closing); font-style: italic; font-weight: var(--fw-medium); line-height: 1.36; hyphens: auto; }
.stack__closing-text { color: var(--stack-fg); }
.stack__closing-text p { margin: 0 0 var(--space-3); }
.stack .stack__closing-highlight { margin: var(--space-5) 0 0; color: var(--stack-accent); }

/* „Freiwischen“: weiche Kante wandert beim Scrollen von links nach rechts über den Text */
@supports (animation-timeline: view()) {
  @media (prefers-reduced-motion: no-preference) {
    .stack__wipe {
      -webkit-mask-image: linear-gradient(90deg, #000 40%, transparent 60%);
      mask-image: linear-gradient(90deg, #000 40%, transparent 60%);
      -webkit-mask-size: 260% 100%; mask-size: 260% 100%;
      -webkit-mask-repeat: no-repeat; mask-repeat: no-repeat;
      animation: stack-wipe linear both;
      animation-timeline: view();
      animation-range: entry 20% cover 45%;
    }
    .stack__wipe--late { animation-range: entry 60% cover 55%; }
  }
}
@keyframes stack-wipe {
  from { -webkit-mask-position: 100% 0; mask-position: 100% 0; }
  to   { -webkit-mask-position: 0 0;    mask-position: 0 0; }
}

@media (max-width: 1023px) {
  .stack__grid { grid-template-columns: minmax(0, 1fr); gap: var(--space-8); }
  .stack__rail { position: static; }
  .stack { --strip: 52px; }
  .stack__card { top: calc(var(--stack-top) + var(--i) * var(--strip)); min-height: 300px; }
  .stack__list { gap: var(--space-6); }
}
@media (max-width: 767px) {
  .stack__card { min-height: 280px; margin-inline: calc(var(--gutter) * -0.5); padding-inline: 20px; }
  .stack .stack__meta { margin-bottom: var(--space-5); }
  .stack__closing { margin-top: var(--space-10); }
}
@media (prefers-reduced-motion: reduce) {
  .stack__card { position: static; box-shadow: none; }
}