*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

:root {
  --bg: #111;
  --bg-surface: #1a1a1a;
  --text: #e8e8e8;
  --text-muted: #888;
  --border: #333;
  --gap: 4px;
  --max-width: 1200px;
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto,
    "Helvetica Neue", Arial, sans-serif;
}

html {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  min-height: 100vh;
}

/* ---- Header ---- */

.site-header {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 2rem 1rem 1.5rem;
  text-align: center;
}

.site-title {
  color: var(--text);
  text-decoration: none;
  font-size: 1.25rem;
  font-weight: 600;
  letter-spacing: 0.02em;
}

.site-title:hover {
  color: #fff;
}

.site-description {
  color: var(--text-muted);
  font-size: 0.875rem;
  margin-top: 0.25rem;
}

/* ---- Gallery Grid ---- */

.gallery {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--gap);
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--gap);
}

.gallery-item {
  aspect-ratio: 1;
  overflow: hidden;
  cursor: pointer;
  border: none;
  padding: 0;
  background: var(--bg-surface);
  display: block;
  position: relative;
}

.gallery-item img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
  transition: transform 0.3s ease, opacity 0.3s ease;
}

.gallery-item:hover img,
.gallery-item:focus-visible img {
  transform: scale(1.03);
  opacity: 0.85;
}

.gallery-item:focus-visible {
  outline: 2px solid var(--text);
  outline-offset: -2px;
}

/* ---- Empty State ---- */

.gallery-empty {
  max-width: var(--max-width);
  margin: 4rem auto;
  padding: 2rem;
  text-align: center;
  color: var(--text-muted);
}

.gallery-empty h2 {
  font-size: 1.25rem;
  margin-bottom: 0.5rem;
  color: var(--text);
}

.gallery-empty code {
  background: var(--bg-surface);
  padding: 0.15em 0.4em;
  border-radius: 3px;
  font-size: 0.9em;
}

/* ---- Lightbox ---- */

.lightbox {
  position: fixed;
  inset: 0;
  z-index: 1000;
  background: rgba(0, 0, 0, 0.95);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.2s ease, visibility 0.2s ease;
}

.lightbox[aria-hidden="false"] {
  opacity: 1;
  visibility: visible;
}

.lightbox-close {
  position: absolute;
  top: 0.75rem;
  right: 0.75rem;
  background: none;
  border: none;
  color: var(--text);
  font-size: 1.75rem;
  cursor: pointer;
  padding: 0.5rem;
  line-height: 1;
  z-index: 1001;
  border-radius: 4px;
}

.lightbox-close:hover {
  color: #fff;
}

.lightbox-close:focus-visible {
  outline: 2px solid var(--text);
  outline-offset: 2px;
}

.lightbox-content {
  display: flex;
  flex-direction: column;
  align-items: center;
  max-height: 100vh;
  max-width: 100vw;
  padding: 3rem 1rem 1.5rem;
  overflow-y: auto;
}

.lightbox-image {
  max-height: 72vh;
  max-width: 90vw;
  object-fit: contain;
  display: block;
  border: 3vmin solid #fff;
  box-shadow: 0 4px 24px rgba(0, 0, 0, 0.5);
}

.lightbox-nav {
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  background: none;
  border: none;
  color: var(--text);
  font-size: 2.5rem;
  cursor: pointer;
  padding: 1rem;
  opacity: 0.6;
  transition: opacity 0.2s ease;
  line-height: 1;
  border-radius: 4px;
}

.lightbox-nav:hover {
  opacity: 1;
}

.lightbox-nav:focus-visible {
  outline: 2px solid var(--text);
  outline-offset: 2px;
  opacity: 1;
}

.lightbox-prev {
  left: 0;
}

.lightbox-next {
  right: 0;
}

/* ---- Lightbox EXIF ---- */

.lightbox-exif {
  margin-top: 1rem;
  text-align: center;
  color: var(--text-muted);
  font-size: 0.8125rem;
  line-height: 1.7;
  max-width: 600px;
}

.lightbox-title {
  color: var(--text);
  font-size: 1rem;
  font-weight: 600;
}

.lightbox-caption {
  margin-top: 0.15rem;
  margin-bottom: 0.5rem;
}

.lightbox-camera {
  color: var(--text);
}

.lightbox-exposure {
  letter-spacing: 0.02em;
}

.lightbox-date {
  margin-top: 0.15rem;
  font-size: 0.75rem;
}

/* ---- Screen-reader only ---- */

.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;
}

/* ---- Footer ---- */

.site-footer {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 2rem 1rem;
  text-align: center;
  color: var(--text-muted);
  font-size: 0.75rem;
}

/* ---- Prevent scroll when lightbox open ---- */

body.lightbox-open {
  overflow: hidden;
}

/* ---- Responsive ---- */

@media (max-width: 768px) {
  .gallery {
    grid-template-columns: repeat(2, 1fr);
  }

  .lightbox-nav {
    font-size: 1.75rem;
    padding: 0.75rem;
  }
}

@media (max-width: 480px) {
  .gallery {
    grid-template-columns: 1fr;
    gap: 2px;
    padding: 0 2px;
  }

  .lightbox-image {
    max-height: 55vh;
    max-width: 100vw;
  }

  .lightbox-content {
    padding: 3rem 0.5rem 1rem;
  }

  .site-header {
    padding: 1.5rem 1rem 1rem;
  }
}