/* コンテンツレイアウト */
.articles-content {
  padding: 4rem 0;
  background-color: var(--background-light);
}

.articles-layout {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.5rem;
}

/* サイドバー */
.articles-sidebar {
  order: -1;
  max-width: 88vw;
}

.sidebar-section {
  background-color: var(--white);
  border-radius: var(--border-radius);
  padding: 2rem;
  margin-bottom: 2rem;
  box-shadow: var(--box-shadow);
}

.sidebar-title {
  font-size: var(--font-size-xl);
  font-weight: var(--font-weight-bold);
  color: var(--text-color);
  margin-bottom: 1.5rem;
  padding-bottom: 0.5rem;
  border-bottom: 2px solid var(--border-color);
}

/* 検索フォーム */
.search-form {
  margin-bottom: 0;
}

.search-input-group {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.search-input {
  padding: 0.75rem;
  border: 1px solid var(--border-color);
  border-radius: var(--border-radius);
  font-size: var(--font-size-base);
  transition: var(--transition);
}

.search-input:focus {
  outline: none;
  border-color: var(--primary-color);
  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
}

.search-btn {
  padding: 0.75rem 1.5rem;
  background-color: var(--primary-color);
  color: var(--white);
  border: none;
  border-radius: var(--border-radius);
  font-weight: var(--font-weight-medium);
  cursor: pointer;
  transition: var(--transition);
}

.search-btn:hover:not(:disabled) {
  background-color: var(--secondary-color);
}

.search-btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
  background-color: #ccc;
  color: #666;
}

.search-btn.loading {
  position: relative;
  color: transparent;
}

.search-btn.loading::after {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 16px;
  height: 16px;
  border: 2px solid #666;
  border-top: 2px solid transparent;
  border-radius: 50%;
  animation: spin 1s linear infinite;
}

@keyframes spin {
  0% {
    transform: translate(-50%, -50%) rotate(0deg);
  }

  100% {
    transform: translate(-50%, -50%) rotate(360deg);
  }
}

.search-form.focused {
  box-shadow: 0 0 0 2px var(--primary-color);
  border-radius: var(--border-radius);
}

/* 読書進捗バー */
.reading-progress {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 3px;
  background-color: rgba(0, 0, 0, 0.1);
  z-index: 1001;
}

.reading-progress-bar {
  height: 100%;
  background-color: var(--primary-color);
  width: 0%;
  transition: width 0.3s ease;
}

/* カテゴリーリスト */
.category-list {
  list-style: none;
}

.category-item {
  margin-bottom: 0.5rem;
}

.category-link {
  display: block;
  padding: 0.75rem 1rem;
  color: var(--text-color);
  text-decoration: none;
  border-radius: var(--border-radius);
  transition: var(--transition);
  border: 1px solid transparent;
}

.category-link:hover {
  background-color: var(--background-light);
  border-color: var(--border-color);
}

.category-link.active {
  background-color: var(--primary-color);
  color: var(--white);
  font-weight: var(--font-weight-medium);
}

/* 最新記事 */
.recent-articles {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.recent-article {
  padding-bottom: 1.5rem;
  border-bottom: 1px solid var(--border-color);
}

.recent-article:last-child {
  border-bottom: none;
  padding-bottom: 0;
}

.recent-article-title a {
  font-size: var(--font-size-base);
  font-weight: var(--font-weight-medium);
  color: var(--text-color);
  text-decoration: none;
  line-height: 1.4;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
  transition: var(--transition);
}

.recent-article-title a:hover {
  color: var(--primary-color);
}

.recent-article-meta {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-top: 0.5rem;
  font-size: var(--font-size-sm);
  color: var(--text-light);
}

.recent-article-category {
  background-color: var(--background-light);
  padding: 0.25rem 0.5rem;
  border-radius: 12px;
  font-size: var(--font-size-xs);
}

/* メインコンテンツ */
.articles-main {
  order: 0;
  max-width: 88vw;
}

.filter-info {
  background-color: var(--white);
  padding: 1.5rem;
  border-radius: var(--border-radius);
  margin-bottom: 2rem;
  box-shadow: var(--box-shadow);
}

.search-info,
.category-info {
  margin-bottom: 1rem;
  color: var(--text-color);
}

.clear-filters {
  color: var(--primary-color);
  text-decoration: none;
  font-weight: var(--font-weight-medium);
}

.clear-filters:hover {
  text-decoration: underline;
}

/* 記事なしの場合 */
.no-articles {
  background-color: var(--white);
  padding: 4rem 2rem;
  text-align: center;
  border-radius: var(--border-radius);
  box-shadow: var(--box-shadow);
}

.no-articles h2 {
  font-size: var(--font-size-2xl);
  color: var(--text-color);
  margin-bottom: 1rem;
}

.no-articles p {
  color: var(--text-light);
  margin-bottom: 1rem;
  line-height: 1.6;
}

/* 記事グリッド */
.articles-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2rem;
  margin-bottom: 3rem;
}

.article-card {
  background-color: var(--white);
  border-radius: var(--border-radius);
  overflow: hidden;
  box-shadow: var(--box-shadow);
  transition: var(--transition);
  display: flex;
  flex-direction: column;
}

.article-card:hover {
  transform: translateY(-5px);
  box-shadow: var(--box-shadow-lg);
}

.article-image {
  position: relative;
  overflow: hidden;
  height: 200px;
  background-color: var(--background-light);
}

.article-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: var(--transition);
}

.article-card:hover .article-image img {
  transform: scale(1.05);
}

.article-content {
  padding: 1.5rem;
  flex: 1;
  display: flex;
  flex-direction: column;
}

.article-category-tag {
  display: inline-block;
  background-color: var(--primary-color);
  color: var(--white);
  padding: 0.25rem 0.75rem;
  border-radius: 12px;
  font-size: var(--font-size-xs);
  font-weight: var(--font-weight-medium);
  margin-bottom: 1rem;
  align-self: flex-start;
  transition: all 0.3s;
}

.article-category-tag:hover {
  background-color: var(--secondary-color);
}

.article-title {
  margin-bottom: 1rem;
  flex-shrink: 0;
}

.article-title a {
  font-size: var(--font-size-xl);
  font-weight: var(--font-weight-bold);
  color: var(--text-color);
  text-decoration: none;
  line-height: 1.4;
  transition: var(--transition);
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.article-title a:hover {
  color: var(--primary-color);
}

.article-excerpt {
  color: var(--text-light);
  line-height: 1.6;
  margin-bottom: 1.5rem;
  flex: 1;
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.article-meta {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 1rem;
  font-size: var(--font-size-sm);
  color: var(--text-light);
}

.article-author {
  font-weight: var(--font-weight-medium);
}

.article-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.article-tag {
  background-color: var(--background-light);
  color: var(--text-light);
  padding: 0.25rem 0.5rem;
  border-radius: 12px;
  font-size: var(--font-size-xs);
  font-weight: var(--font-weight-medium);
}

/* ページネーション */
.pagination {
  background-color: var(--white);
  padding: 2rem;
  border-radius: var(--border-radius);
  box-shadow: var(--box-shadow);
  text-align: center;
}

.pagination-info {
  color: var(--text-light);
  margin-bottom: 1.5rem;
  font-size: var(--font-size-sm);
}

.pagination-list {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 0.5rem;
  flex-wrap: wrap;
}

.pagination-link {
  display: block;
  padding: 0.75rem 1rem;
  color: var(--text-color);
  text-decoration: none;
  border: 1px solid var(--border-color);
  border-radius: var(--border-radius);
  transition: var(--transition);
  min-width: 44px;
  text-align: center;
}

.pagination-link:hover {
  background-color: var(--background-light);
  border-color: var(--primary-color);
}

.pagination-link.active {
  background-color: var(--primary-color);
  color: var(--white);
  border-color: var(--primary-color);
}

/* アニメーション */
.animate-on-scroll {
  opacity: 0;
  transform: translateY(30px);
  transition: all 0.6s ease;
}

.animate-on-scroll.animate-in {
  opacity: 1;
  transform: translateY(0);
}

/* モーダルとトースト */
.image-modal {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: 2000;
  opacity: 0;
  visibility: hidden;
  transition: all 0.3s ease;
}

.image-modal.show {
  opacity: 1;
  visibility: visible;
}

.image-modal-overlay {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-color: rgba(0, 0, 0, 0.9);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 2rem;
}

.image-modal-content {
  position: relative;
  max-width: 90%;
  max-height: 90%;
}

.modal-image {
  max-width: 100%;
  max-height: 100%;
  object-fit: contain;
}

.modal-close {
  position: absolute;
  top: -2rem;
  right: -2rem;
  width: 2rem;
  height: 2rem;
  background-color: rgba(255, 255, 255, 0.9);
  border: none;
  border-radius: 50%;
  font-size: 1.2rem;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
}

.toast {
  position: fixed;
  bottom: 2rem;
  left: 50%;
  transform: translateX(-50%) translateY(100px);
  background-color: var(--text-color);
  color: var(--white);
  padding: 1rem 2rem;
  border-radius: var(--border-radius);
  box-shadow: var(--box-shadow-lg);
  z-index: 1500;
  opacity: 0;
  transition: all 0.3s ease;
}

.toast.show {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}

/* タブレット以上 */
@media (min-width: 768px) {
  .articles-sidebar {
    order: 1;
  }

  .articles-main {
    order: 0;
  }

  .articles-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .search-input-group {
    flex-direction: row;
    gap: 0.5rem;
  }

  .search-btn {
    flex-shrink: 0;
  }
}

/* デスクトップ */
@media (min-width: 1024px) {
  .articles-layout {
    grid-template-columns: 3fr 1fr;
    gap: 2rem;
  }

  .search-input-group {
    flex-direction: column;
    gap: 0.5rem;
  }

  .search-btn {
    align-self: stretch;
  }
}