/* ============================================================
   AI観測ラボ ブログ — articles.css
   記事一覧ページ固有スタイル
   CSS変数・ヘッダー・フッターは observatory-common.css で管理
   2026.02
   ============================================================ */

/* ===== リセット ===== */
.arc-wrap *,
.arc-wrap *::before,
.arc-wrap *::after {
  box-sizing: border-box;
}

/* ===== テーマ制限解除 ===== */
#secondary, .sidebar, .widget-area {
  display: none !important;
}

.page .entry-content {
  max-width: 100% !important;
  padding: 0 !important;
  background: transparent !important;
  border: none !important;
  box-shadow: none !important;
  margin: 0 !important;
}

/* ===== ラッパー ===== */
.arc-wrap {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 40px 80px;
  font-family: var(--font-sans);
}
/* ===== ラッパー ===== */
.arc-wrap {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 40px 80px;
  font-family: var(--font-sans);
}


/* ============================================================
   HERO — コンパクト
   ============================================================ */
.arc-hero {
  position: relative;
  overflow: hidden;
  margin: 0 -40px 0;
  padding: 52px 40px 80px;
}

.arc-hero-starmap {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  z-index: 0;
}

.arc-hero-orb {
  position: absolute;
  width: 400px;
  height: 400px;
  border-radius: 50%;
  background: radial-gradient(circle, #C9D9F0 0%, transparent 70%);
  filter: blur(80px);
  top: -100px;
  right: -60px;
  opacity: .38;
  pointer-events: none;
  z-index: 0;
}

.arc-hero-inner {
  position: relative;
  z-index: 10;
  max-width: 640px;
}

.arc-hero-eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: .22em;
  text-transform: uppercase;
  color: var(--star-blue);
  margin-bottom: 18px;
  animation: arcIn .6s .1s both;
}
.arc-hero-eyebrow::before {
  content: '';
  display: block;
  width: 24px;
  height: 1px;
  background: var(--star-blue);
}

.arc-hero-title {
  font-family: var(--font-serif);
  font-weight: 300;
  font-size: clamp(36px, 4.2vw, 54px);
  line-height: 1.1;
  letter-spacing: -.01em;
  color: var(--ink);
  margin-bottom: 14px;
  animation: arcIn .7s .22s both;
  border: none !important;
  padding: 0 !important;
}
.arc-hero-title em {
  font-style: italic;
  color: var(--star-blue);
}

.arc-hero-desc {
  font-size: 13px;
  line-height: 1.9;
  color: var(--ink-soft);
  animation: arcIn .7s .38s both;
}

/* ボトムメタ */
.arc-hero-meta {
  position: absolute;
  bottom: 24px;
  left: 40px;
  display: flex;
  align-items: center;
  gap: 18px;
  z-index: 10;
}
.arc-hero-meta-stat {
  display: flex;
  flex-direction: column;
  gap: 2px;
}
.arc-hero-meta-stat strong {
  font-family: var(--font-mono);
  font-size: 17px;
  font-weight: 400;
  color: var(--ink);
  letter-spacing: .04em;
}
.arc-hero-meta-stat span {
  font-family: var(--font-mono);
  font-size: 8px;
  letter-spacing: .16em;
  color: var(--ink-soft);
  text-transform: uppercase;
}
.arc-hero-meta-divider {
  width: 1px;
  height: 28px;
  background: var(--line-strong);
}
.arc-hero-meta-coord {
  font-family: var(--font-mono);
  font-size: 8px;
  letter-spacing: .12em;
  color: var(--star-blue);
  opacity: .38;
  margin-left: 6px;
}


/* ============================================================
   FILTER TABS
   ============================================================ */
.arc-filter {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 20px 0 0;
  border-bottom: 1px solid var(--line-strong);
  margin-bottom: 40px;
  position: relative;
}
.arc-filter::after {
  content: '';
  position: absolute;
  bottom: -1px;
  left: 0;
  width: 44px;
  height: 2px;
  background: var(--star-blue);
}

.arc-filter-inner {
  display: flex;
  align-items: flex-end;
  gap: 0;
  flex-wrap: wrap;
}

.arc-filter-tab {
  display: flex;
  align-items: baseline;
  gap: 5px;
  padding: 10px 18px 12px;
  border: none;
  border-bottom: 2px solid transparent;
  background: transparent;
  cursor: pointer;
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: .14em;
  text-transform: uppercase;
  color: var(--ink-soft);
  transition: color var(--transition), border-color var(--transition);
  white-space: nowrap;
  margin-bottom: -1px;
}
.arc-filter-tab:hover {
  color: var(--ink);
}
.arc-filter-tab.active {
  color: var(--ink);
  border-bottom-color: var(--star-blue);
  background: transparent !important;
  background-color: transparent !important;
  color: var(--ink) !important;
}

.arc-filter-inner button,
.arc-filter-inner button.arc-filter-tab,
.arc-filter-inner button.arc-filter-tab.active {
  background: transparent !important;
  background-color: transparent !important;
  color: var(--ink-soft) !important;
}

.arc-filter-inner button.arc-filter-tab.active {
  color: var(--ink) !important;
  border-bottom-color: var(--star-blue) !important;
}

.arc-filter-tab {
  background-color: transparent !important;
}

.arc-filter-tab-en {
  font-size: 10px;
}
.arc-filter-tab-count {
  font-size: 8px;
  color: var(--star-blue);
  opacity: .65;
  letter-spacing: .1em;
}
.arc-filter-tab.active .arc-filter-tab-count {
  opacity: 1;
}

.arc-filter-result {
  display: flex;
  align-items: baseline;
  gap: 5px;
  flex-shrink: 0;
  padding-bottom: 12px;
}
.arc-filter-result-num {
  font-family: var(--font-mono);
  font-size: 20px;
  font-weight: 400;
  color: var(--ink);
  letter-spacing: .04em;
  transition: color var(--transition);
}
.arc-filter-result-label {
  font-family: var(--font-mono);
  font-size: 8px;
  letter-spacing: .18em;
  color: var(--ink-soft);
  text-transform: uppercase;
}


/* ============================================================
   ARTICLES GRID — 2カラム
   ============================================================ */
.arc-grid-section {
  min-height: 400px;
}

.arc-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 2px;
  background: var(--line);
}

/* カード */
.arc-card {
  display: flex;
  flex-direction: column;
  text-decoration: none;
  background: var(--white);
  position: relative;
  overflow: hidden;
  transition:
    transform var(--transition),
    box-shadow var(--transition);
}
.arc-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 12px 32px rgba(107,143,191,.13);
  z-index: 2;
}

/* サムネイル */
.arc-card-img {
  width: 100%;
  aspect-ratio: 16 / 9;
  overflow: hidden;
  background: var(--bg2);
  position: relative;
  flex-shrink: 0;
}
.arc-card-img img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
  transition: transform .42s ease;
}
.arc-card:hover .arc-card-img img {
  transform: scale(1.04);
}

/* プレースホルダー */
.arc-card-img-placeholder {
  width: 100%;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--bg2);
}

/* ログバッジ */
.arc-badge {
  position: absolute;
  top: 10px;
  left: 10px;
  font-family: var(--font-mono);
  font-size: 8px;
  letter-spacing: .15em;
  color: var(--star-blue);
  background: rgba(244,246,251,.92);
  border: 1px solid var(--line-strong);
  padding: 3px 8px;
  backdrop-filter: blur(4px);
}

/* カテゴリバッジ */
.arc-cat-badge {
  position: absolute;
  bottom: 10px;
  right: 10px;
  font-family: var(--font-mono);
  font-size: 8px;
  letter-spacing: .12em;
  color: var(--white);
  background: rgba(30,34,53,.72);
  padding: 3px 9px;
  backdrop-filter: blur(4px);
}

/* ボディ */
.arc-card-body {
  padding: 22px 24px 28px;
  display: flex;
  flex-direction: column;
  flex: 1;
}

.arc-card-meta {
  display: flex;
  gap: 12px;
  font-family: var(--font-mono);
  font-size: 9px;
  letter-spacing: .1em;
  color: var(--ink-soft);
  margin-bottom: 10px;
}

.arc-card-title {
  font-family: var(--font-sans);
  font-size: 15px;
  font-weight: 500;
  line-height: 1.7;
  color: var(--ink);
  margin-bottom: 10px;
  transition: color var(--transition);
  flex: 1;
}
.arc-card:hover .arc-card-title {
  color: var(--star-blue);
}

.arc-card-excerpt {
  font-size: 12px;
  line-height: 1.8;
  color: var(--ink-soft);
  margin-bottom: 16px;
}

.arc-card-read {
  font-family: var(--font-mono);
  font-size: 9px;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--star-blue);
  opacity: 0;
  transform: translateX(-4px);
  transition: opacity var(--transition), transform var(--transition);
  margin-top: auto;
}
.arc-card:hover .arc-card-read {
  opacity: 1;
  transform: translateX(0);
}


/* ============================================================
   EMPTY STATE
   ============================================================ */
.arc-empty {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 20px;
  padding: 80px 40px;
  color: var(--ink-soft);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .12em;
}


/* ============================================================
   ANIMATIONS
   ============================================================ */
@keyframes arcIn {
  from { opacity: 0; transform: translateY(12px); }
  to   { opacity: 1; transform: translateY(0); }
}
@keyframes arcPulse {
  0%, 100% { opacity: .5; }
  50%       { opacity: .9; }
}

.arc-star-pulse  { animation: arcPulse 3s ease-in-out infinite; }
.arc-star-pulse2 { animation: arcPulse 4.5s ease-in-out .8s infinite; }


/* ============================================================
   RESPONSIVE
   ============================================================ */
@media (max-width: 860px) {
  .arc-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 680px) {
  .arc-wrap {
    padding: 0 20px 60px;
  }
  .arc-hero {
    margin: 0 -20px 0;
    padding: 44px 20px 70px;
  }
  .arc-hero-title {
    font-size: clamp(30px, 8.5vw, 42px) !important;
  }
  .arc-hero-meta {
    left: 20px;
    gap: 12px;
  }
  .arc-hero-meta-coord {
    display: none;
  }
  .arc-filter {
    flex-direction: column;
    align-items: flex-start;
    gap: 12px;
  }
  .arc-filter-inner {
    gap: 0;
    width: 100%;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    padding-bottom: 2px;
    /* スクロールバー非表示 */
    scrollbar-width: none;
  }
  .arc-filter-inner::-webkit-scrollbar { display: none; }
  .arc-filter-tab {
    padding: 8px 14px 10px;
    font-size: 9px;
  }
  .arc-filter-result {
    padding-bottom: 0;
  }
  .arc-card-body {
    padding: 18px 20px 22px;
  }
  .arc-card-title {
    font-size: 14px;
  }
}