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

:root {
  --gap: 6px;
  --header-h: 52px;
}

body {
  font-family: 'General Sans', -apple-system, sans-serif;
  background: #fff;
  color: #111;
}

/* Header */
header {
  position: sticky;
  top: 0;
  z-index: 100;
  height: var(--header-h);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 24px;
  background: rgba(255,255,255,0.95);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid #f0f0f0;
}

.logo {
  font-family: 'Satoshi', sans-serif;
  font-size: 26px;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  text-decoration: none;
  color: inherit;
}

nav {
  display: flex;
  gap: 24px;
}

nav a {
  font-size: 12px;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  text-decoration: none;
  color: #888;
  transition: color 0.15s;
}

nav a:hover,
nav a.active {
  color: #111;
}

/* Grid */
main {
  display: flex;
  gap: var(--gap);
  padding: var(--gap);
  align-items: flex-start;
  width: 100%;
  box-sizing: border-box;
}

.grid-col {
  flex: 1 1 0;
  min-width: 0;
  display: flex;
  flex-direction: column;
  gap: var(--gap);
}

.photo-item {
  cursor: pointer;
  overflow: hidden;
  background: #f4f4f4;
  width: 100%;
}

.photo-item img {
  display: block;
  width: 100%;
  height: auto;
  transition: opacity 0.2s;
}

.photo-item img.loading {
  opacity: 0;
}

.photo-item:hover img {
  opacity: 0.88;
}


/* Footer */
footer {
  text-align: center;
  padding: 48px 24px;
  font-size: 13px;
  letter-spacing: 0.06em;
  color: #111;
}

/* Lightbox */
#lightbox {
  position: fixed;
  inset: 0;
  z-index: 200;
  background: rgba(0,0,0,0.96);
  display: flex;
  align-items: center;
  justify-content: center;
}

#lightbox[hidden] { display: none; }

#lb-img-wrap {
  max-width: 90vw;
  max-height: 90vh;
  display: flex;
  align-items: center;
  justify-content: center;
}

#lb-img {
  max-width: 90vw;
  max-height: 90vh;
  object-fit: contain;
  display: block;
}

#lb-close,
#lb-prev,
#lb-next {
  position: fixed;
  background: none;
  border: none;
  color: #fff;
  cursor: pointer;
  font-size: 32px;
  line-height: 1;
  padding: 12px;
  opacity: 0.7;
  transition: opacity 0.15s;
  -webkit-tap-highlight-color: transparent;
}

#lb-close:hover,
#lb-prev:hover,
#lb-next:hover { opacity: 1; }

#lb-close { top: 16px; right: 20px; font-size: 22px; }
#lb-prev   { left: 12px; top: 50%; transform: translateY(-50%); font-size: 48px; }
#lb-next   { right: 12px; top: 50%; transform: translateY(-50%); font-size: 48px; }

/* Empty state */
.empty {
  width: 100%;
  text-align: center;
  padding: 120px 24px;
  color: #bbb;
  font-size: 13px;
  letter-spacing: 0.05em;
}

/* Responsive */
@media (max-width: 700px)  { :root { --gap: 4px; } }

@media (max-width: 600px) {
  header { padding: 0 16px; }
  nav { gap: 16px; }
  #lb-prev { left: 4px; }
  #lb-next { right: 4px; }
}