/* ===================================================
   column.css — コラム一覧ページ
   =================================================== */

/* ---- Popular slider ---- */
.col-slider-section {
  background: #fff;
  padding: 40px 0 36px;
  border-bottom: 1px solid var(--border);
}

.col-slider-header {
  max-width: 1200px;
  margin: 0 auto 20px;
  padding: 0 24px;
}

.col-slider-label {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 0.72rem;
  font-weight: 800;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--yellow-hover);
  background: var(--yellow-light);
  padding: 5px 12px;
  border-radius: 99px;
}

.col-slider-viewport {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
  overflow: hidden;
}

.col-slider-track {
  display: flex;
  gap: 16px;
  transition: transform 0.5s cubic-bezier(0.25, 1, 0.5, 1);
}

/* ---- Slide card ---- */
.col-slide {
  flex: 0 0 calc((100% - 32px) / 3);
  aspect-ratio: 16 / 9;
  border-radius: 16px;
  overflow: hidden;
  text-decoration: none;
  display: block;
  position: relative;
  box-shadow: 0 4px 20px rgba(0,0,0,0.1);
  transition: transform 0.22s ease, box-shadow 0.22s ease;
}

.col-slide:hover {
  transform: translateY(-4px);
  box-shadow: 0 12px 36px rgba(0,0,0,0.18);
}

/* Category pill on slide — top-left overlay */
.col-slide-cat-strip {
  position: absolute;
  top: 12px;
  left: 12px;
  z-index: 3;
  font-size: 0.68rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  color: #fff;
  padding: 3px 10px;
  border-radius: 99px;
  writing-mode: horizontal-tb;
}

.col-strip--strategy { background: rgba(55,65,81,0.85); }
.col-strip--aiseo    { background: rgba(37,99,235,0.85); }
.col-strip--tech     { background: rgba(8,145,178,0.85); }
.col-strip--trend    { background: rgba(234,88,12,0.85); }
.col-strip--aio      { background: rgba(124,58,237,0.85); }

/* background image area */
.col-slide-bg {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
}

.col-slide-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(to top, rgba(0,0,0,0.78) 0%, rgba(0,0,0,0.12) 50%, transparent 100%);
}

.col-slide-body {
  position: relative;
  z-index: 1;
  padding: 20px;
}

.col-slide-date {
  font-size: 0.72rem;
  color: rgba(255,255,255,0.6);
  margin-bottom: 8px;
  font-weight: 500;
}

.col-slide-title {
  font-size: 0.9rem;
  font-weight: 700;
  color: #fff;
  line-height: 1.5;
  letter-spacing: -0.01em;
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

/* ---- Dots ---- */
.col-slider-dots {
  display: flex;
  justify-content: center;
  gap: 6px;
  margin-top: 20px;
}

.col-slider-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: #d1d5db;
  border: none;
  cursor: pointer;
  padding: 0;
  transition: background 0.2s, width 0.2s;
}

.col-slider-dot.active {
  background: var(--dark);
  width: 24px;
  border-radius: 4px;
}

/* =============================================
   SUBNAV
   ============================================= */
.col-subnav {
  background: #fff;
  border-bottom: 1px solid #e9ecef;
  padding: 12px 0;
}

.col-subnav-inner {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 40px;
  flex-wrap: wrap;
}

.col-subnav-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 6px;
  text-decoration: none;
  color: #6b7280;
  transition: color 0.2s ease;
}

.col-subnav-item svg {
  width: 28px;
  height: 28px;
  color: #9ca3af;
  transition: color 0.2s ease;
}

.col-subnav-item span {
  font-size: 0.75rem;
  font-weight: 700;
}

.col-subnav-item:hover,
.col-subnav-item.active {
  color: #111827;
}

.col-subnav-item:hover svg,
.col-subnav-item.active svg {
  color: var(--yellow-hover);
}

/* ---- Hero ---- */
.col-hero {
  padding: 110px 0 56px;
  background: #ffffff;
  border-bottom: 1px solid #e9ecef;
}

.col-hero .container { position: relative; z-index: 1; }

.col-breadcrumb {
  font-size: 0.78rem;
  color: #9ca3af;
  margin-bottom: 32px;
}
.col-breadcrumb a {
  color: #9ca3af;
  text-decoration: none;
}
.col-breadcrumb a:hover { color: #0891b2; }
.col-breadcrumb span { margin: 0 6px; }

.col-hero-title {
  font-size: clamp(3rem, 8vw, 5.5rem);
  font-weight: 900;
  color: #7DD9ED;
  line-height: 1;
  letter-spacing: -0.03em;
  margin-bottom: 10px;
}

.col-hero-sub {
  font-size: 1rem;
  color: #4b5563;
  font-weight: 500;
}

/* ---- Section ---- */
.col-section {
  padding: 64px 0 80px;
  background: #f4f6f9;
}

/* ---- Category filter (Tabs) ---- */
.col-tabs {
  display: flex;
  margin-bottom: 40px;
  border-bottom: 1px solid #d1d5db;
  gap: 2px;
}

.col-tab-btn {
  background: #fff;
  border: 1px solid #d1d5db;
  border-bottom: none;
  border-radius: 8px 8px 0 0;
  padding: 14px 24px;
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--gray);
  cursor: pointer;
  flex: 1;
  text-align: center;
  position: relative;
  transition: all 0.2s ease;
}

.col-tab-btn:hover {
  background: #f9fafb;
  color: var(--dark);
}

.col-tab-btn.active {
  background: #fcd34d; /* Yellow */
  color: #111827;
  border-color: #fcd34d;
  z-index: 2;
}

/* Triangle for active tab */
.col-tab-btn.active::after {
  content: '';
  position: absolute;
  bottom: -8px;
  left: 50%;
  transform: translateX(-50%);
  border-left: 8px solid transparent;
  border-right: 8px solid transparent;
  border-top: 8px solid #fcd34d;
}

/* =============================================
   LAYOUT (MAIN & SIDEBAR)
   ============================================= */
.col-main-layout {
  display: flex;
  gap: 40px;
  align-items: flex-start;
}

.col-main-content {
  flex: 1;
  min-width: 0;
}

.col-sidebar {
  width: 300px;
  flex-shrink: 0;
  display: flex;
  flex-direction: column;
  gap: 32px;
}

/* Sidebar Widgets */
.col-sidebar-banner a {
  display: block;
  background: linear-gradient(135deg, #ecfeff 0%, #cffafe 100%);
  border: 1.5px solid #a5f3fc;
  color: #0e7490;
  padding: 32px 24px;
  border-radius: 16px;
  text-decoration: none;
  box-shadow: 0 4px 16px rgba(8,145,178,0.1);
  transition: transform 0.2s, box-shadow 0.2s;
  text-align: center;
}

.col-sidebar-banner a:hover {
  transform: translateY(-4px);
  box-shadow: 0 10px 28px rgba(8,145,178,0.18);
}

.col-sidebar-banner h4 {
  font-size: 1.1rem;
  font-weight: 800;
  margin-bottom: 12px;
  line-height: 1.4;
  color: #0e7490;
}

.col-sidebar-banner p {
  font-size: 0.85rem;
  line-height: 1.6;
  margin-bottom: 24px;
  color: #374151;
}

.col-banner-btn {
  display: inline-block;
  background: #0891b2;
  color: #fff;
  font-weight: 700;
  font-size: 0.9rem;
  padding: 10px 24px;
  border-radius: 99px;
  transition: background 0.18s;
}

.col-sidebar-banner a:hover .col-banner-btn {
  background: #0e7490;
}

.col-widget-title {
  font-size: 1.1rem;
  font-weight: 800;
  color: #111827;
  margin-bottom: 16px;
  padding-bottom: 12px;
  border-bottom: 2px solid #e5e7eb;
}

.col-widget-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.col-widget-tags a {
  background: #fff;
  border: 1px solid #d1d5db;
  color: #4b5563;
  padding: 6px 12px;
  border-radius: 6px;
  font-size: 0.8rem;
  text-decoration: none;
  font-weight: 500;
  transition: all 0.2s;
}

.col-widget-tags a:hover {
  background: #f3f4f6;
  border-color: #9ca3af;
  color: #111827;
}

/* =============================================
   FEATURED ARTICLE
   ============================================= */
.col-featured {
  margin-bottom: 48px;
}

.col-featured-card {
  display: grid;
  grid-template-columns: 420px 1fr;
  background: #fff;
  border: 1.5px solid var(--border);
  border-radius: 20px;
  overflow: hidden;
  text-decoration: none;
  transition: transform 0.22s ease, box-shadow 0.22s ease, border-color 0.22s ease;
  min-height: 300px;
}

.col-featured-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 20px 48px rgba(0,0,0,0.1);
  border-color: rgba(125,217,237,0.4);
}

.col-featured-thumb {
  position: relative;
  display: flex;
  flex-direction: column;
  justify-content: flex-start;
  padding: 28px;
  overflow: hidden;
}

.col-thumb-content {
  position: relative;
  z-index: 1;
  display: flex;
  align-items: center;
  justify-content: flex-end;
}

.col-thumb-tag {
  display: inline-block;
  background: rgba(255,255,255,0.18);
  color: rgba(255,255,255,0.9);
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  padding: 4px 12px;
  border-radius: 99px;
  border: 1px solid rgba(255,255,255,0.25);
  backdrop-filter: blur(4px);
}

.col-thumb-date {
  font-size: 0.78rem;
  color: rgba(255,255,255,0.5);
}

.col-featured-body {
  padding: 36px 40px;
  display: flex;
  flex-direction: column;
  justify-content: center;
}

.col-featured-meta {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 16px;
}

.col-featured-title {
  font-size: 1.25rem;
  font-weight: 800;
  color: var(--dark);
  line-height: 1.5;
  letter-spacing: -0.02em;
  margin-bottom: 14px;
}

.col-featured-excerpt {
  font-size: 0.9rem;
  color: var(--gray);
  line-height: 1.75;
  margin-bottom: 24px;
  flex: 1;
}

.col-featured-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.col-author {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.82rem;
  color: var(--gray);
  font-weight: 500;
}

.col-author-avatar {
  width: 28px;
  height: 28px;
  background: var(--yellow-light);
  border: 1.5px solid rgba(125,217,237,0.4);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.65rem;
  font-weight: 800;
  color: var(--yellow-hover);
}

.col-read-more {
  font-size: 0.82rem;
  font-weight: 700;
  color: var(--yellow-hover);
}

/* =============================================
   ARTICLE GRID
   ============================================= */
.col-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
  margin-bottom: 48px;
}

.col-card {
  background: #fff;
  border: 1.5px solid var(--border);
  border-radius: 18px;
  overflow: hidden;
  text-decoration: none;
  display: flex;
  flex-direction: column;
  position: relative;
  transition: transform 0.22s ease, box-shadow 0.22s ease, border-color 0.22s ease;
}

.col-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 14px 36px rgba(0,0,0,0.09);
  border-color: rgba(125,217,237,0.45);
}

/* ---- Thumbnails (shared colors) ---- */
.col-card-thumb,
.col-featured-thumb {
  height: 160px;
  position: relative;
  overflow: hidden;
  flex-shrink: 0;
}

.col-thumb--dark   { background: linear-gradient(145deg, #111827 0%, #374151 100%); }
.col-thumb--blue   { background: linear-gradient(145deg, #1d4ed8 0%, #38bdf8 100%); }
.col-thumb--teal   { background: linear-gradient(145deg, #0369a1 0%, #7DD9ED 100%); }
.col-thumb--purple { background: linear-gradient(145deg, #6d28d9 0%, #c084fc 100%); }
.col-thumb--orange { background: linear-gradient(145deg, #c2410c 0%, #fb923c 100%); }
.col-thumb--green  { background: linear-gradient(145deg, #15803d 0%, #4ade80 100%); }

/* decorative circles */
.col-card-thumb::before,
.col-featured-thumb::before {
  content: '';
  position: absolute;
  top: -30px;
  right: -30px;
  width: 140px;
  height: 140px;
  background: rgba(255,255,255,0.06);
  border-radius: 50%;
  pointer-events: none;
}

.col-thumb-label {
  position: absolute;
  bottom: 16px;
  left: 16px;
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  color: rgba(255,255,255,0.8);
  background: rgba(0,0,0,0.2);
  padding: 3px 10px;
  border-radius: 99px;
  backdrop-filter: blur(4px);
}

/* Category pill badge — top-left of thumbnail */
.col-card-cat {
  position: absolute;
  top: 12px;
  left: 12px;
  height: auto;
  width: auto;
  writing-mode: horizontal-tb;
  font-size: 0.7rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  color: #fff;
  padding: 3px 10px;
  border-radius: 99px;
  z-index: 3;
}

.col-cat-bg--aiseo    { background: #2563eb; }
.col-cat-bg--strategy { background: #374151; }
.col-cat-bg--tech     { background: #0891b2; }
.col-cat-bg--trend    { background: #ea580c; }
.col-cat-bg--aio      { background: #7c3aed; }

.col-card-thumb {
  padding-left: 0;
}

/* ---- Card body ---- */
.col-card-body {
  padding: 22px 24px 24px 24px;
  display: flex;
  flex-direction: column;
  flex: 1;
}

.col-card-meta {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 10px;
}

.col-card-title {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--dark);
  line-height: 1.55;
  margin-bottom: 10px;
  letter-spacing: -0.01em;
  flex: 1;
}

.col-card-excerpt {
  font-size: 0.82rem;
  color: var(--gray);
  line-height: 1.7;
  margin-bottom: 14px;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.col-card-author {
  font-size: 0.78rem;
  color: #9ca3af;
  font-weight: 500;
  margin-top: auto;
}

/* ---- Category badges ---- */
.col-cat-badge {
  display: inline-block;
  font-size: 0.72rem;
  font-weight: 700;
  padding: 3px 9px;
  border-radius: 99px;
}

.col-cat--aiseo    { background: #eff6ff; color: #1d4ed8; }
.col-cat--strategy { background: #111827; color: #fff; }
.col-cat--tech     { background: #ecfeff; color: #0369a1; }
.col-cat--trend    { background: #fff7ed; color: #c2410c; }
.col-cat--aio      { background: #f5f3ff; color: #6d28d9; }

/* Hide old badges since we now use vertical strips */
.col-card-meta .col-cat-badge {
  display: none;
}

.col-date {
  font-size: 0.78rem;
  color: #9ca3af;
}

/* ---- Load more ---- */
.col-more {
  text-align: center;
}

.col-more-btn {
  background: transparent;
  border: 1.5px solid var(--border);
  border-radius: 99px;
  padding: 12px 36px;
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--dark);
  cursor: pointer;
  transition: background 0.18s, border-color 0.18s;
}

.col-more-btn:hover {
  background: var(--dark);
  border-color: var(--dark);
  color: #fff;
}

/* ---- Empty ---- */
.col-empty {
  text-align: center;
  padding: 64px 0;
  color: var(--gray);
  font-size: 0.95rem;
}

/* ---- CTA ---- */
.col-cta {
  background: var(--dark);
  padding: 56px 0;
  position: relative;
  overflow: hidden;
}

.col-cta::before {
  content: '';
  position: absolute;
  inset: 0;
  background-image: radial-gradient(rgba(125,217,237,0.1) 1px, transparent 1px);
  background-size: 24px 24px;
  pointer-events: none;
}

.col-cta-inner {
  position: relative;
  z-index: 1;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 32px;
  flex-wrap: wrap;
}

.col-cta-label {
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--yellow);
  margin-bottom: 10px;
}

.col-cta-title {
  font-size: 1.5rem;
  font-weight: 800;
  color: #fff;
  letter-spacing: -0.02em;
  margin-bottom: 8px;
}

.col-cta-sub {
  font-size: 0.875rem;
  color: rgba(255,255,255,0.5);
}

.col-cta-actions {
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  gap: 12px;
  flex-shrink: 0;
}

.col-cta-link {
  font-size: 0.82rem;
  color: rgba(255,255,255,0.45);
  text-decoration: underline;
  text-underline-offset: 2px;
  transition: color 0.18s;
}

.col-cta-link:hover { color: rgba(255,255,255,0.75); }

/* ---- Responsive ---- */
@media (max-width: 900px) {
  /* Featured card */
  .col-featured-card { grid-template-columns: 1fr; }
  .col-featured-thumb { min-height: 200px; height: 200px; }
  .col-featured-body { padding: 28px; }

  /* Grid */
  .col-grid { grid-template-columns: repeat(2, 1fr); }

  /* Slider */
  .col-slide { flex: 0 0 calc((100% - 16px) / 2); }

  /* Sidebar stacks below main content */
  .col-main-layout { flex-direction: column; }
  .col-sidebar { width: 100%; flex-direction: row; flex-wrap: wrap; gap: 20px; }
  .col-sidebar-banner, .col-sidebar-widget { flex: 1 1 280px; }

  /* Subnav */
  .col-subnav-inner { gap: 20px; }
}

@media (max-width: 600px) {
  /* Hero */
  .col-hero { padding: 100px 0 40px; }
  .col-hero-title { font-size: clamp(2.4rem, 10vw, 3.5rem); }

  /* Subnav */
  .col-subnav-inner { gap: 12px; overflow-x: auto; justify-content: flex-start; padding: 0 16px; flex-wrap: nowrap; }
  .col-subnav-item { flex-shrink: 0; }
  .col-subnav-item svg { width: 22px; height: 22px; }

  /* Tabs — 横スクロール */
  .col-tabs { overflow-x: auto; flex-wrap: nowrap; gap: 0; border-bottom: 1px solid #d1d5db; -webkit-overflow-scrolling: touch; }
  .col-tab-btn { flex: 0 0 auto; padding: 12px 16px; font-size: 0.82rem; white-space: nowrap; }
  .col-tab-btn.active::after { display: none; }

  /* Featured */
  .col-featured-thumb { height: 180px; min-height: 180px; }
  .col-featured-title { font-size: 1.05rem; }
  .col-featured-body { padding: 20px; }
  .col-featured-excerpt { display: none; }

  /* Grid */
  .col-grid { grid-template-columns: 1fr; gap: 16px; }

  /* Sidebar */
  .col-sidebar { flex-direction: column; }
  .col-sidebar-banner a { padding: 24px 20px; }

  /* CTA */
  .col-cta { padding: 40px 0; }
  .col-cta-inner { flex-direction: column; align-items: flex-start; gap: 24px; }
  .col-cta-actions { align-items: flex-start; width: 100%; }
  .col-cta-title { font-size: 1.2rem; }
  .btn-cta-primary { width: 100%; text-align: center; }

  /* Slider */
  .col-slider-section { padding: 28px 0 24px; }
  .col-slide { flex: 0 0 calc(100% - 40px); }
  .col-slide-title { font-size: 0.85rem; }

  /* Section padding */
  .col-section { padding: 40px 0 56px; }
}