/* 記事カード代表画像（ファイルなし・404時はグラデ＋頭文字 — 一覧ページと共通） */
.article-card-thumb {
  position: relative;
  width: 100%;
  overflow: hidden;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  display: flex;
  align-items: center;
  justify-content: center;
}

.article-card-thumb--list {
  height: 200px;
  flex-shrink: 0;
}

.article-card-thumb--top {
  aspect-ratio: 16 / 10;
  flex-shrink: 0;
}

.article-card-thumb-letter {
  font-size: 48px;
  font-weight: 700;
  color: #fff;
  line-height: 1;
  user-select: none;
  z-index: 0;
}

.article-card-thumb--top .article-card-thumb-letter {
  font-size: 2.25rem;
}

.article-card-thumb img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
  z-index: 1;
}

.article-card-thumb img.is-hidden {
  display: none;
}