/* Base styles */
* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}
html {
  font-family: "Helvetica Neue", Arial, sans-serif;
  font-size: 16px;
  line-height: 1.4;
}
body {
  color: #000;
  width: 100%;
}
a {
  color: inherit;
  text-decoration: none;
}

/* Image sizing inside gallery */
.item img {
  display: block;
  width: 100%;
  height: auto;
}

/* Gallery image width utility classes */
.img-w-25 { width: 25%; max-width: 120px; }
.img-w-50 { width: 50%; max-width: 220px; }
.img-w-75 { width: 75%; max-width: 320px; }
.img-w-100 { width: 100%; }

@media (min-width: 768px) {
  .img-w-25 { max-width: 160px; }
  .img-w-50 { max-width: 280px; }
  .img-w-75 { max-width: 420px; }
}

/* Section titles */
.section-title {
  /* font-size: 1rem; */
  /* font-weight: 600; */
  margin-bottom: 1.2rem;
}

/* Top bar */
header.top-bar {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  align-items: flex-start;
  padding: 0.5rem 1rem;
  font-size: 0.75rem;
}
.top-bar {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  align-items: flex-start;
  padding: 0.5rem 1rem;
  font-size: 0.75rem;
}
.top-bar .menu {
  display: flex;
  gap: 1rem;
  list-style: none;
}
.top-bar .date {
  margin-top: 0.25rem;
}

/* Generic section spacing */
section {
  margin: 3rem auto;
  width: min(90%, 1200px);
}

/* Make direct children of <main> span the full viewport width */
main > * {
  width: 100%;
  max-width: 100%;
}

/* Gallery layout (flex for varied widths) */
.gallery {
  display: flex;
  flex-wrap: wrap;
  gap: 2rem;
  align-items: flex-start;
}
.gallery .item {
  text-align: center;
  font-size: 0.625rem;
}

/* 12-column utilities */
[class*="col-span-"] {
  grid-column-end: span var(--span);
}
.col-span-1 {--span:1}
.col-span-2 {--span:2}
.col-span-3 {--span:3}
.col-span-4 {--span:4}
.col-span-5 {--span:5}
.col-span-6 {--span:6}
.col-span-7 {--span:7}
.col-span-8 {--span:8}
.col-span-9 {--span:9}
.col-span-10 {--span:10}
.col-span-11 {--span:11}
.col-span-12 {--span:12}

.start-1 {grid-column-start:1}
.start-2 {grid-column-start:2}
.start-3 {grid-column-start:3}
.start-4 {grid-column-start:4}
.start-5 {grid-column-start:5}
.start-6 {grid-column-start:6}
.start-7 {grid-column-start:7}
.start-8 {grid-column-start:8}
.start-9 {grid-column-start:9}
.start-10 {grid-column-start:10}
.start-11 {grid-column-start:11}
.start-12 {grid-column-start:12}

/* Existing grid layout (fallback/other use) */
.grid-4 {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
  gap: 1.5rem;
}
.grid-4 .item {
  text-align: center;
  font-size: 0.625rem;
}
.grid-4 .item.rotated img {
  transform: rotate(-8deg);
}
.caption {
  display: block;
  margin-top: 0.25rem;
}

/* Gesture */
.gesture {
  text-align: left;
}
/* Custom header bar inside each section */
.gesture .top-bar {
  position: relative;
  display: grid;
  grid-template-columns: repeat(12, 1fr);
  align-items: baseline;
  padding: 0 0.5rem;
  border-bottom: 1px solid #ccc;
  margin-bottom: 1rem;
  column-gap: 0.5rem;
}
.gesture .section-title {
  margin-bottom: 0; /* override default */
}
.gesture .section-desc {
  font-size: 0.75rem;
}
.gesture img {
  width: 40vw;
  max-width: 240px;
}
.gesture .caption {
  font-size: 0.625rem;
  margin-top: 0.5rem;
}

/* Birds pair */
.grid-2 {
  display: flex;
  justify-content: center;
  gap: 2rem;
}
.grid-2 img {
  width: 42vw;
  max-width: 260px;
}

/* Arrow / Mosquito icon sections */
.arrow-section,
.mosquito {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  gap: 0.75rem;
}
.circle-icon {
  width: 38vw;
  max-width: 200px;
}
.small-caption {
  font-size: 0.625rem;
  max-width: 220px;
}

/* Footer banner */
.footer-banner {
  position: relative;
  text-align: center;
}
.footer-banner img {
  width: 60vw;
  max-width: 350px;
}
.page-end {
  font-size: 18vw;
  font-weight: 700;
  color: rgba(0, 0, 0, 0.04);
  margin-top: -5vw;
  pointer-events: none;
}
.credits {
  margin-top: 2rem;
  font-size: 0.625rem;
  display: flex;
  justify-content: space-between;
  width: 100%;
  max-width: 100%;
  padding-inline: 1rem;
}

/* Accessibility */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

/* Larger screens */
@media (min-width: 768px) {
  html {
    font-size: 18px;
  }
  .grid-4 {
    grid-template-columns: repeat(4, 1fr);
  }
  .gesture img {
    width: 200px;
  }
  .grid-2 img {
    width: 260px;
  }
  .circle-icon {
    width: 200px;
  }
  .page-end {
    font-size: 10vw;
    margin-top: -3vw;
  }
}

.caption {
  font-size: 0.8rem;
  font-weight: 400;
  color: rgba(0, 0, 0, 0.75);
  /* font-family: "Diatype Semi-Mono Variable", sans-serif; */
  font-style: normal;
  line-height: 1.35;
  letter-spacing: 0;
  display: block;
  width: 100%;
  font-variation-settings: 'slnt' 0, 'MONO' 0.5;
  border-bottom: 0.1rem solid rgba(0, 0, 0, 0.4);
  border-left: 0.1rem solid rgba(0, 0, 0, 0.4);
  padding: 0.4rem 0 0.4rem 0.8rem;
  margin-top: 0.5rem;
}

/* Flying object animation */
.flying-object {
  position: fixed;
  left: -60px;
  width: 40px;
  height: auto;
  pointer-events: none;
  animation: flyAcross 12s linear infinite;
}

@keyframes flyAcross {
  from {
    transform: translateX(0);
  }
  to {
    transform: translateX(calc(100vw + 60px));
  }
}

/* ---------------- Sticky Header & Footer ---------------- */
/* Base hide mobile variants */
.mobile-bar,
.mobile-credits {
  display: none;
}

/* Desktop (≥768px) fixed header & footer */
@media (min-width: 768px) {
  header.top-bar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: #fff;
    border-bottom: 1px solid #ddd;
  }
  footer.credits {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: #fff;
    border-top: 1px solid #ddd;
  }
  /* compensate for fixed bars */
  main {
    padding-top: 3.5rem;
    padding-bottom: 3rem;
  }
}

/* Mobile (≤767px) show mobile variants, hide desktop bars */
@media (max-width: 767px) {
  header.top-bar,
  footer.credits {
    display: none;
  }

  .mobile-bar,
  .mobile-credits {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 100%;
    background: #fff;
    z-index: 1000;
    padding: 0.65rem 1rem;
    font-size: 0.75rem;
  }
  .mobile-bar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    border-bottom: 1px solid #ddd;
  }
  .mobile-credits .mobile-menu {
    display: flex;
    gap: 0.75rem;
    list-style: none;
    padding: 0;
    margin: 0;
  }
  .mobile-credits .mobile-menu a {
    text-decoration: none;
  }
  .mobile-credits {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    border-top: 1px solid #ddd;
  }
  main {
    padding-top: 2.8rem;
    padding-bottom: 2.5rem;
  }
}