/* ══════════════════════════════════════════════════════════════════════
   Causes Amplify — Moment 3: One Interest, Many Channels (Cluster Explainer)
   Enforces Apple HIG Design System, Authentic Media Framing, and Zero Emojis
   ══════════════════════════════════════════════════════════════════════ */

.cluster-explainer {
  background: var(--system-background, #ffffff);
  border: 1px solid var(--separator, rgba(60, 60, 67, 0.12));
  border-radius: var(--radius-lg, 20px);
  padding: 36px 36px 32px;
  box-shadow: 0 4px 24px -2px rgba(0, 0, 0, 0.05);
  position: relative;
}

.cluster-explainer .card-header {
  margin-bottom: 24px;
}

.cluster-explainer .doc-meta-label {
  color: var(--causes-red, #ed2224);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  margin-bottom: 6px;
}

.cluster-explainer .card-title {
  font-size: clamp(26px, 2.8vw, 34px);
  font-weight: 800;
  letter-spacing: -0.02em;
  color: var(--label, #0f172a);
  margin: 0 0 8px 0;
  line-height: 1.15;
}

.cluster-explainer .card-desc {
  font-size: 17px;
  line-height: 1.5;
  color: #334155;
  margin: 0;
  max-width: 68ch;
}

/* ── 1. The Core Concern Hero Capsule ── */
.cluster-concern-capsule {
  background: linear-gradient(135deg, rgba(46, 51, 140, 0.04) 0%, rgba(46, 51, 140, 0.01) 100%);
  border: 1px solid rgba(46, 51, 140, 0.14);
  border-radius: var(--radius-md, 14px);
  padding: 22px 28px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 32px;
  margin-bottom: 28px;
  position: relative;
  overflow: hidden;
}

.cluster-concern-capsule::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 4px;
  background: var(--causes-indigo, #2e338c);
  border-radius: 4px 0 0 4px;
}

.cluster-concern-left {
  flex: 0 0 auto;
}

.cluster-concern-tag {
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--causes-indigo, #2e338c);
  margin-bottom: 4px;
  display: flex;
  align-items: center;
  gap: 6px;
}

.cluster-concern-tag svg {
  width: 14px;
  height: 14px;
  flex-shrink: 0;
}

.cluster-concern-title {
  font-size: clamp(28px, 3.2vw, 36px);
  font-weight: 800;
  letter-spacing: -0.025em;
  color: var(--label, #0f172a);
  margin: 0;
  line-height: 1.1;
}

.cluster-concern-divider {
  width: 1px;
  height: 48px;
  background: rgba(46, 51, 140, 0.16);
  flex-shrink: 0;
}

.cluster-concern-right {
  flex: 1 1 auto;
  max-width: 44ch;
}

.cluster-concern-quote-label {
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  color: var(--secondary-label, #64748b);
  margin-bottom: 4px;
}

.cluster-concern-quote {
  font-size: clamp(17px, 1.8vw, 20px);
  font-weight: 500;
  font-style: italic;
  color: #1e293b;
  line-height: 1.4;
  margin: 0;
}

/* ── 2. Channels Section Eyebrow ── */
.cluster-section-label {
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--secondary-label, #64748b);
  margin-bottom: 16px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.cluster-section-label::after {
  content: '';
  flex: 1;
  height: 1px;
  background: var(--separator, rgba(60, 60, 67, 0.12));
}

/* ── 3. Three Channel Cards Grid ── */
.cluster-channel-columns {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
  margin-bottom: 28px;
}

/* Card Architecture (Apple HIG Elevated Card) */
.cluster-explainer .cluster-channel {
  background: var(--system-background, #ffffff);
  border: 1px solid var(--separator, rgba(60, 60, 67, 0.14));
  border-radius: var(--radius-lg, 18px);
  box-shadow: 0 4px 16px -2px rgba(0, 0, 0, 0.04);
  display: flex;
  flex-direction: column;
  overflow: hidden;
  position: relative;
  transition: all 0.35s cubic-bezier(0.32, 0.72, 0, 1);
  min-width: 0;
  padding: 0;
}

.cluster-explainer .cluster-channel:hover {
  transform: translateY(-2px);
  box-shadow: 0 10px 24px -4px rgba(46, 51, 140, 0.1);
  border-color: rgba(46, 51, 140, 0.28);
}

/* Channel Signature Top Bar */
.cluster-card-bar {
  height: 4px;
  width: 100%;
  flex-shrink: 0;
}
.cluster-card-groceries .cluster-card-bar { background: var(--causes-indigo, #2e338c); }
.cluster-card-bills .cluster-card-bar { background: var(--causes-red, #ed2224); }
.cluster-card-choices .cluster-card-bar { background: var(--causes-green, #117a3d); }

/* Card Header Area */
.cluster-card-header {
  padding: 18px 20px 14px;
  display: flex;
  flex-direction: column;
}

.cluster-card-badge {
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  padding: 4px 10px;
  border-radius: 9999px;
  display: inline-flex;
  align-items: center;
  gap: 5px;
  width: fit-content;
  margin-bottom: 10px;
}

.cluster-card-groceries .cluster-card-badge {
  background: rgba(46, 51, 140, 0.08);
  color: var(--causes-indigo, #2e338c);
}
.cluster-card-bills .cluster-card-badge {
  background: rgba(237, 34, 36, 0.08);
  color: var(--causes-red, #ed2224);
}
.cluster-card-choices .cluster-card-badge {
  background: rgba(17, 122, 61, 0.08);
  color: var(--causes-green, #117a3d);
}

.cluster-card-name {
  font-size: 20px;
  font-weight: 750;
  letter-spacing: -0.015em;
  color: var(--label, #0f172a);
  margin: 0 0 6px 0;
  line-height: 1.25;
}

.cluster-card-perspective {
  font-size: 13.5px;
  line-height: 1.45;
  color: #475569;
  margin: 0;
  min-height: 2.8em;
}

/* Media Frame (Clean Creator Clip Thumbnail) */
.cluster-media-frame {
  margin: 0 16px;
  border-radius: var(--radius-md, 12px);
  overflow: hidden;
  position: relative;
  aspect-ratio: 4 / 3;
  background: #0f172a;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.06);
}

.cluster-clip-image {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

.cluster-card-groceries .cluster-clip-image { object-position: center 45%; }
.cluster-card-bills .cluster-clip-image { object-position: center 25%; }
.cluster-card-choices .cluster-clip-image { object-position: center 40%; }

.cluster-media-scrim {
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(0,0,0,0) 50%, rgba(0,0,0,0.55) 100%);
  pointer-events: none;
}

.cluster-media-tag {
  position: absolute;
  bottom: 8px;
  left: 10px;
  background: rgba(15, 23, 42, 0.72);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border: 1px solid rgba(255, 255, 255, 0.2);
  color: #ffffff;
  font-size: 10px;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  padding: 2px 7px;
  border-radius: 6px;
  display: inline-flex;
  align-items: center;
  gap: 4px;
}

.cluster-media-tag svg {
  width: 10px;
  height: 10px;
}

/* Example Story Box */
.cluster-story-box {
  margin: auto 16px 18px;
  padding: 12px 14px;
  background: var(--secondary-system-background, #f8fafc);
  border: 1px solid rgba(0, 0, 0, 0.05);
  border-radius: var(--radius-md, 12px);
  display: flex;
  flex-direction: column;
}

.cluster-story-eyebrow {
  font-size: 10px;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--secondary-label, #64748b);
  margin-bottom: 3px;
  display: block;
}

.cluster-story-headline {
  font-size: 14.5px;
  font-weight: 700;
  line-height: 1.35;
  color: var(--label, #0f172a);
  margin: 0;
}

/* ── 4. The Shared Learning Banner ── */
.cluster-learning-banner {
  display: flex;
  align-items: center;
  gap: 18px;
  padding: 18px 24px;
  background: linear-gradient(135deg, rgba(46, 51, 140, 0.05) 0%, rgba(46, 51, 140, 0.02) 100%);
  border: 1px solid rgba(46, 51, 140, 0.16);
  border-radius: var(--radius-md, 14px);
}

.cluster-learning-icon-box {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: #ffffff;
  border: 1px solid rgba(46, 51, 140, 0.16);
  box-shadow: 0 2px 8px rgba(46, 51, 140, 0.08);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  color: var(--causes-indigo, #2e338c);
}

.cluster-learning-icon-box svg {
  width: 22px;
  height: 22px;
}

.cluster-learning-text h3 {
  font-size: 16px;
  font-weight: 750;
  letter-spacing: -0.01em;
  line-height: 1.3;
  margin: 0 0 3px 0;
  color: var(--label, #0f172a);
}

.cluster-learning-text p {
  margin: 0;
  font-size: 14px;
  line-height: 1.5;
  color: #334155;
}

.cluster-example-note {
  font-size: 11.5px;
  color: var(--secondary-label, #64748b);
  margin: 14px 0 0 0;
  line-height: 1.45;
}

/* ── 5. Responsive Viewport Adaptations ── */
@media (max-width: 768px) {
  .cluster-explainer {
    padding: 24px 20px 20px;
  }
  .cluster-concern-capsule {
    flex-direction: column;
    align-items: flex-start;
    gap: 14px;
    padding: 18px 20px;
  }
  .cluster-concern-divider {
    display: none;
  }
  .cluster-channel-columns {
    grid-template-columns: 1fr;
    gap: 16px;
  }
  .cluster-explainer .cluster-channel {
    width: 100%;
  }
  .cluster-learning-banner {
    align-items: flex-start;
    padding: 16px;
  }
}