.report-container {
  padding: 4rem 2rem;
  max-width: 960px;
  margin: 0 auto;
}
.section-header {
  margin-bottom: 2.5rem;
  text-align: center;
}
.section-header h2 {
  font-size: 2rem;
  font-weight: 700;
  color: #2c3e50;
  margin: 0 0 0.5rem 0;
}
.section-header p {
  font-size: 1rem;
  color: #7f8c8d;
  color: #ea5532;
  margin: 0;
}

/* --- メインのカテゴリタブ --- */
.category-tab-nav {
  display: flex;
  border-bottom: 2px solid #e0e0e0;
  margin-bottom: 2rem;
}
.category-tab-item {
  padding: 1rem 1.5rem;
  cursor: pointer;
  font-size: 1.1rem;
  font-weight: 600;
  color: #7f8c8d;
  position: relative;
  transition: color 0.3s;
}
.category-tab-item:hover {
  color: #2c3e50;
}
.category-tab-item.is-active {
  color: #3498db;
}
.category-tab-item::after {
  content: "";
  position: absolute;
  bottom: -2px;
  left: 0;
  width: 100%;
  height: 2px;
  background-color: #3498db;
  transform: scaleX(0);
  transition: transform 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
}
.category-tab-item.is-active::after {
  transform: scaleX(1);
}

/* --- メインのコンテンツ --- */
.category-tab-content {
  display: none;
  animation: fadeIn 0.5s ease-in-out;
}
.category-tab-content.is-active {
  display: block;
}
@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(10px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* --- サブの年度タブ --- */
.year-tab-nav {
  display: flex;
  gap: 0.5rem;
  margin-bottom: 2rem;
}
.year-tab-item {
  padding: 0.6rem 1.2rem;
  cursor: pointer;
  font-size: 0.9rem;
  font-weight: 600;
  color: #34495e;
  background-color: #ecf0f1;
  border-radius: 2rem;
  border: 1px solid transparent;
  transition: all 0.3s;
}
.year-tab-item:hover {
  border-color: #bdc3c7;
}
.year-tab-item.is-active {
  background-color: #3498db;
  color: #ffffff;
  border-color: #3498db;
}

/* --- サブのコンテンツ --- */
.year-tab-content {
  display: none;
}
.year-tab-content.is-active {
  display: block;
  animation: fadeIn 0.4s;
}

/* --- ファイルリストのスタイル --- */
.file-list {
  list-style: none;
  padding: 0;
  margin: 0;
}
.file-item {
  display: flex;
  align-items: center;
  padding: 1.25rem 0.85rem;
  border-bottom: 1px solid #e9ecef;
  transition: background-color 0.2s;
}
.file-item:hover {
  background-color: #ffffff;
}
.file-item__date {
  flex: 0 0 80px;
  font-size: 0.9rem;
  color: #7f8c8d;
  font-weight: 600;
}
.file-item__title {
  flex: 1 1 auto;
  margin: 0;
  font-weight: 600;
  color: #2c3e50;
}
.download-button {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.6rem 1.2rem;
  background-color: #3498db;
  color: #ffffff;
  text-decoration: none;
  font-size: 0.9rem;
  font-weight: 600;
  border-radius: 5px;
  transition: background-color 0.2s;
}
.download-button:hover {
  background-color: #2980b9;
}
.download-button svg {
  width: 1em;
  height: 1em;
}
.download-button.filetype-excel {
  background-color: #1d6f42;
}
.download-button.filetype-excel:hover {
  background-color: #185c37;
}
.download-button img {
  width: 1em;
  height: 1em;
}
/* --- スマホ対応 --- */
@media (max-width: 768px) {
  .report-container {
    padding: 3rem 1rem;
  }
  .category-tab-item {
    padding: 0.8rem 0.5rem;
    font-size: 0.9rem;
    flex-grow: 1;
    text-align: center;
  }
  .year-tab-nav {
    flex-wrap: wrap;
  }
  .file-item {
    flex-direction: column;
    align-items: flex-start;
    gap: 0.8rem;
  }
  .file-item__title {
    width: 100%;
  }
}