/* ==========================================================================
   Home page, "tiles" design (site_design: tiles in _config.yml)
   Markup: _includes/home/tiles-{de,en}.html. Loaded after theme-tiles.css on
   the home page only; the carousel styles come from home.css.
   ========================================================================== */

/* ---------------------------------------------------------------- hero */
.tiles-hero {
  padding: 4.5rem 0 0;
  background: var(--color-white);
}

.tiles-hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.1fr) minmax(0, 0.9fr);
  gap: 4rem;
  align-items: center;
}

.tiles-hero-copy h1 {
  margin-bottom: 1.25rem;
  line-height: 1.05;
}

.tiles-hero-lead {
  max-width: 56ch;
  margin-bottom: 2rem;
  font-size: 1.15rem;
  line-height: 1.7;
  color: var(--color-text);
}

.tiles-hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
}

/* The mosaic: a 2 × 2 arrangement on a 4 × 4 grid. The top-right and
   bottom-left quadrants are 2 × 2 photo tiles; the top-left and bottom-right
   quadrants are each a 2 × 2 of small squares with one corner left open
   (top-left corner above, bottom-right corner below), so the cluster steps
   from the top right to the bottom left like the header image on fh-ooe.at.
   The photos show group pictures from the pool in _data/home_mosaic.yml and
   take turns fading to another one every few seconds (initMosaic in
   main.js); the small
   squares are flat colour only, the AIST blue and its tints. */
.tile-mosaic {
  --tile-gap: 8px;
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  grid-template-rows: repeat(4, minmax(0, 1fr));
  gap: var(--tile-gap);
  aspect-ratio: 1;
  width: 100%;
  max-width: 33rem;
  margin-left: auto;
}

.tile {
  position: relative;
  display: block;
  min-width: 0;
  min-height: 0;
  overflow: hidden;
  text-decoration: none;
}

/* explicit placement (row-start / col-start / row-end / col-end) */
.tile:nth-child(1) { grid-area: 1 / 2 / 2 / 3; }   /* light blue  (top-left quadrant, top right)    */
.tile:nth-child(2) { grid-area: 1 / 3 / 3 / 5; }   /* photo 1     (top-right quadrant)              */
.tile:nth-child(3) { grid-area: 2 / 2 / 3 / 3; }   /* AIST blue   (top-left quadrant, bottom right) */
.tile:nth-child(4) { grid-area: 2 / 1 / 3 / 2; }   /* sky         (top-left quadrant, bottom left)  */
.tile:nth-child(5) { grid-area: 3 / 1 / 5 / 3; }   /* photo 2     (bottom-left quadrant)            */
.tile:nth-child(6) { grid-area: 3 / 3 / 4 / 4; }   /* mid blue    (bottom-right quadrant, top left) */
.tile:nth-child(7) { grid-area: 3 / 4 / 4 / 5; }   /* sky         (bottom-right quadrant, top right)*/
.tile:nth-child(8) { grid-area: 4 / 3 / 5 / 4; }   /* AIST blue   (bottom-right quadrant, bottom left) */

.tile-blue { background: var(--color-primary); }
.tile-mid { background: var(--color-primary-500); }
.tile-light { background: var(--color-primary-light); }
.tile-sky { background: var(--sky-200); }

/* Photo tiles hold two stacked images: the visible one (.is-front) and a
   spare that main.js loads the next picture into. The incoming picture
   fades in on top of the current one, which stays underneath (.is-behind)
   until the fade is over, so no background ever shows through. */
.tile-photo {
  background: var(--sky-100);
}

.tile-photo img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
  opacity: 0;
  z-index: 0;
  transition: opacity 1.2s ease, transform 0.6s var(--ease);
}

.tile-photo img.is-front {
  opacity: 1;
  z-index: 2;
}

.tile-photo img.is-behind {
  opacity: 1;
  z-index: 1;
  transition: none;
}

.tile-photo:hover img,
.tile-photo:focus-visible img {
  transform: scale(1.06);
}

@media (prefers-reduced-motion: no-preference) {
  .tile {
    opacity: 0;
    transform: scale(0.85);
    animation: tile-in 0.55s var(--ease) forwards;
    animation-delay: calc(var(--i, 0) * 60ms);
  }
}

@keyframes tile-in {
  to {
    opacity: 1;
    transform: none;
  }
}

/* numbers strip: four cells separated by hairlines */
.tiles-stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  list-style: none;
  margin: 3.5rem 0 0;
  padding: 0;
  border-top: 1px solid var(--color-line);
  border-bottom: 1px solid var(--color-line);
}

.tiles-stats li + li {
  border-left: 1px solid var(--color-line);
}

.tiles-stats a {
  display: flex;
  flex-direction: column;
  gap: 0.2rem;
  padding: 1.5rem 1.5rem;
  color: inherit;
  text-decoration: none;
  transition: background-color 0.2s var(--ease);
}

.tiles-stats a:hover,
.tiles-stats a:focus-visible {
  background: var(--color-bg-light);
  text-decoration: none;
}

.tiles-stats .stat-value {
  font-size: 2.4rem;
  font-weight: 700;
  line-height: 1.05;
  letter-spacing: -0.03em;
  color: var(--color-primary);
  font-variant-numeric: tabular-nums;
}

.tiles-stats .stat-label {
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--color-text-light);
}

/* ------------------------------------------------------- research areas */
.area-tiles {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1.5rem;
}

.area-tile {
  /* one palette for all three areas: the AIST blue and its tints */
  --area-color: var(--color-primary);
  --area-soft: var(--sky-100);
  display: flex;
  flex-direction: column;
  min-width: 0;
  padding: 1.75rem 1.75rem 1.5rem;
  background: var(--color-white);
  border: 1px solid var(--color-line);
  border-top: 5px solid var(--area-color);
  transition: border-color 0.2s var(--ease);
}

.area-tile:hover {
  border-color: var(--area-color);
}

.area-tile-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 4.5rem;
  height: 4.5rem;
  margin-bottom: 1.25rem;
  background: var(--area-soft);
}

.area-tile-icon img {
  width: 3.25rem;
  height: 3.25rem;
  object-fit: contain;
}

.area-tile h2 {
  font-size: 1.35rem;
  margin: 0 0 0.75rem;
}

.area-tile > p {
  flex: 1;
  font-size: 0.95rem;
  line-height: 1.7;
}

.area-tile em {
  display: block;
  margin-top: 0.5rem;
  font-size: 0.82rem;
  color: var(--color-text-light);
}

.area-tile .carousel {
  margin-top: 0.25rem;
}

.area-tile .carousel-viewport {
  border-radius: 0;
  border: 1px solid var(--color-line);
  background: var(--color-bg-light);
}

.area-tile-link {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  margin-top: 1rem;
  padding-top: 1rem;
  border-top: 1px solid var(--color-line);
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--area-color);
}

.area-tile-link i {
  font-size: 0.8em;
  transition: transform 0.2s var(--ease);
}

.area-tile-link:hover {
  color: var(--area-color);
  text-decoration: none;
}

.area-tile-link:hover i {
  transform: translateX(3px);
}

/* -------------------------------------------------------------- news */
.tiles-news-grid {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

/* -------------------------------------------------------- quick tiles */
.quick-tiles {
  display: grid;
  grid-template-columns: repeat(6, minmax(0, 1fr));
  gap: 0.75rem;
  list-style: none;
  margin: 0;
  padding: 0;
}

.quick-tiles a {
  position: relative;
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
  gap: 0.2rem;
  aspect-ratio: 1;
  padding: 1.1rem;
  background: var(--color-primary);
  color: var(--color-white);
  text-decoration: none;
  transition: background-color 0.2s var(--ease);
}

.quick-tiles a:hover,
.quick-tiles a:focus-visible {
  background: var(--color-primary-500);
  color: var(--color-white);
  text-decoration: none;
}

.quick-tiles a > i {
  position: absolute;
  top: 1.1rem;
  left: 1.1rem;
  font-size: 1.5rem;
  color: var(--color-primary-light);
  transition: color 0.2s var(--ease);
}

.quick-tiles a:hover > i,
.quick-tiles a:focus-visible > i {
  color: var(--color-white);
}

.quick-tiles a::after {
  content: "\f061";
  font-family: "Font Awesome 6 Free";
  font-weight: 900;
  position: absolute;
  top: 1.1rem;
  right: 1.1rem;
  font-size: 0.8rem;
  opacity: 0.6;
  transition: transform 0.2s var(--ease), opacity 0.2s var(--ease);
}

.quick-tiles a:hover::after,
.quick-tiles a:focus-visible::after {
  opacity: 1;
  transform: translateX(3px);
}

.quick-tiles span {
  font-size: 1.05rem;
  font-weight: 700;
  letter-spacing: -0.01em;
  line-height: 1.2;
}

.quick-tiles small {
  font-size: 0.75rem;
  line-height: 1.3;
  color: rgba(255, 255, 255, 0.7);
}

/* ------------------------------------------------------------ cta band */
.tiles-cta {
  position: relative;
  overflow: hidden;
  padding: 4.5rem 0;
  background: var(--sky-100);
  color: var(--color-text);
}

.tiles-cta .container {
  position: relative;
  z-index: 1;
}

.tiles-cta-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.3fr) auto;
  gap: 2rem;
  align-items: center;
}

.tiles-cta h2 {
  color: var(--color-primary);
  margin-bottom: 0.5rem;
}

.tiles-cta p:last-child {
  margin: 0;
  max-width: 60ch;
}

.tiles-cta .tiles-hero-actions {
  justify-content: flex-end;
}

/* a small cluster of squares echoing the hero mosaic */
.tiles-cta-deco {
  position: absolute;
  right: -1rem;
  bottom: -1rem;
  display: grid;
  grid-template-columns: repeat(3, 4.5rem);
  grid-template-rows: repeat(3, 4.5rem);
  gap: 8px;
  pointer-events: none;
}

.tiles-cta-deco i {
  display: block;
}

.tiles-cta-deco i:nth-child(1) { grid-area: 1 / 3; background: var(--sky-200); }
.tiles-cta-deco i:nth-child(2) { grid-area: 2 / 2; background: var(--color-primary); }
.tiles-cta-deco i:nth-child(3) { grid-area: 2 / 3; background: var(--color-primary-light); }
.tiles-cta-deco i:nth-child(4) { grid-area: 3 / 1; background: var(--color-white); }

/* ------------------------------------------------------------ responsive */
@media (max-width: 1024px) {
  .tiles-hero-grid {
    grid-template-columns: 1fr;
    gap: 2.5rem;
  }

  .tile-mosaic {
    margin-left: 0;
    max-width: 30rem;
  }

  .area-tiles {
    grid-template-columns: 1fr;
  }

  .tiles-news-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .quick-tiles {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .tiles-cta-grid {
    grid-template-columns: 1fr;
  }

  .tiles-cta .tiles-hero-actions {
    justify-content: flex-start;
  }

  .tiles-cta-deco {
    opacity: 0.5;
  }
}

@media (max-width: 640px) {
  .tiles-hero {
    padding-top: 2.5rem;
  }

  .tile-mosaic {
    --tile-gap: 6px;
    max-width: none;
  }

  .tiles-stats {
    grid-template-columns: repeat(2, 1fr);
    margin-top: 2.5rem;
  }

  .tiles-stats li:nth-child(3) {
    border-left: none;
  }

  .tiles-stats li:nth-child(n + 3) {
    border-top: 1px solid var(--color-line);
  }

  .tiles-stats a {
    padding: 1.1rem 1rem;
  }

  .tiles-stats .stat-value {
    font-size: 1.9rem;
  }

  .tiles-news-grid {
    grid-template-columns: 1fr;
  }

  .quick-tiles {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .tiles-cta {
    padding: 3rem 0;
  }
}