:root {
  --bg: #fafaf8;
  --fg: #1c1c1a;
  --muted: #6b6b66;
  --line: #deded8;
  --card: #fff;
  --accent: #2b4a8b;
  color-scheme: light dark;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #17171a;
    --fg: #ececea;
    --muted: #9a9a95;
    --line: #34343a;
    --card: #202024;
    --accent: #8fb0ff;
  }
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font-family: system-ui, -apple-system, "Hiragino Sans", "Noto Sans JP", sans-serif;
  line-height: 1.6;
}

a {
  color: var(--accent);
  text-decoration: none;
}

header {
  position: sticky;
  top: 0;
  z-index: 1;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.5rem 1rem;
  padding: 0.75rem 1rem;
  background: var(--bg);
  border-bottom: 1px solid var(--line);
}

h1 {
  margin: 0;
  font-size: 1.1rem;
}

h1 a {
  color: var(--fg);
}

#search {
  flex: 1 1 14rem;
  max-width: 28rem;
  padding: 0.5rem 0.75rem;
  font-size: 1rem;
  color: var(--fg);
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 8px;
}

#count {
  color: var(--muted);
  font-size: 0.85rem;
}

main {
  max-width: 1200px;
  margin: 0 auto;
  padding: 1rem;
}

.cards {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(15rem, 1fr));
  gap: 0.5rem;
  margin: 0;
  padding: 0;
  list-style: none;
}

.cards a {
  display: flex;
  gap: 0.75rem;
  align-items: baseline;
  height: 100%;
  padding: 0.6rem 0.8rem;
  color: var(--fg);
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 8px;
}

.cards a:hover,
.cards a:focus-visible {
  border-color: var(--accent);
}

.no {
  flex: none;
  min-width: 2.2rem;
  color: var(--accent);
  font-variant-numeric: tabular-nums;
  font-weight: 600;
}

.title {
  overflow: hidden;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  font-size: 0.9rem;
}

.empty {
  padding: 3rem 0;
  color: var(--muted);
  text-align: center;
}

.viewer-nav {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.5rem 1rem;
  margin-bottom: 1rem;
}

.viewer-nav strong {
  min-width: 4rem;
  text-align: center;
}

.button {
  padding: 0.35rem 0.8rem;
  color: var(--fg);
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 8px;
}

.button:hover {
  border-color: var(--accent);
}

.page-image {
  display: block;
  width: 100%;
  height: auto;
  max-width: 1400px;
  margin: 0 auto;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 4px;
}

footer {
  padding: 2rem 1rem;
  color: var(--muted);
  font-size: 0.75rem;
  text-align: center;
}