/* 投稿一覧レイアウト：PC3列 → タブレット2列 → スマホ1列 */
.post-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.5rem;
  margin-top: 2rem;
}

/* 投稿カード：アプリ風に整形 */
.post-card {
  background: #fff;
  border-radius: 12px;
  padding: 1rem;
  box-shadow: 0 4px 10px rgba(0, 0, 0, 0.08);
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  transition: transform 0.2s ease;
  min-height: 200px;
}
.post-card:hover {
  transform: translateY(-3px);
}

/* タグボタン */
.post-card a span {
  background: #ff9800;
  color: white;
  padding: 0.3em 0.8em;
  border-radius: 9999px;
  font-size: 0.8em;
  display: inline-block;
  margin: 2px 4px 0 0;
  text-decoration: none;
}

/* IDバッジ */
.id-badge {
  display: inline-block;
  background: #1abc9c;
  color: white;
  padding: 4px 10px;
  border-radius: 9999px;
  font-size: 0.85em;
  margin-top: 0.5em;
}

/* 投稿日時 */
.post-time {
  margin-top: auto;
  text-align: right;
  font-size: 0.8em;
  color: #17b4b1;
}

/* ヘッダー修正 */
header h1 a {
  color: white;
  text-decoration: none;
}
footer {
  font-size: 0.8em;
  text-align: center;
  background: #17b4b1;
  color: white;
  padding: 1em;
}