/* =============================================
   CASE STUDY — shared styles
   ============================================= */

.cs-hero {
  padding: calc(var(--section-py) + 80px) 0 0;
}

.cs-hero-meta {
  display: flex;
  align-items: center;
  gap: 16px;
  margin-bottom: 32px;
}

.cs-tag {
  display: inline-block;
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: #57695B;
  background: #D8E0D3;
  border-radius: 100px;
  padding: 6px 14px;
}

.cs-hero-heading {
  font-size: clamp(40px, 6vw, 88px);
  font-weight: 300;
  letter-spacing: -0.04em;
  line-height: 1.0;
  color: #1c1c1a;
  margin-bottom: 40px;
}

.cs-hero-desc {
  font-size: clamp(16px, 1.6vw, 20px);
  font-weight: 400;
  line-height: 1.7;
  color: #555;
  margin-bottom: 56px;
}

/* Stats row */
.cs-stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1px;
  border-top: 1px solid var(--color-border);
  border-bottom: 1px solid var(--color-border);
  margin-bottom: 0;
}

.cs-stat {
  padding: 32px 0;
}

.cs-stat-label {
  font-size: 11px;
  font-weight: 500;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-muted);
  margin-bottom: 10px;
}

.cs-stat-value {
  font-size: 15px;
  font-weight: 500;
  color: #1c1c1a;
  line-height: 1.4;
}

/* Hero image */
.cs-hero-img-wrap {
  margin-top: 72px;
  border-radius: 20px;
  overflow: hidden;
  background: #BABFAC;
  aspect-ratio: 16 / 9;
}

.cs-hero-img-wrap img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

/* ── Sections ── */
.cs-section {
  padding: calc(var(--section-py) * 0.65) 0;
}

.cs-section + .cs-section {
  padding-top: 0;
}

.cs-section-label {
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--color-muted);
  margin-bottom: 24px;
}

.cs-section-heading {
  font-size: clamp(25px, 3.15vw, 47px);
  font-weight: 400;
  letter-spacing: -0.03em;
  line-height: 1.2;
  color: #1c1c1a;
  margin-bottom: 28px;
}

.cs-section-subheading {
  font-size: clamp(18px, 1.8vw, 26px);
  font-weight: 500;
  letter-spacing: -0.02em;
  line-height: 1.3;
  color: #1c1c1a;
  margin-bottom: 16px;
}

.cs-section-body {
  font-size: 17.6px;
  line-height: 1.8;
  color: #555;
}

.cs-section-body p + p {
  margin-top: 20px;
}

.cs-section-body ul,
.cs-section-body ol {
  list-style-type: disc;
  padding-left: 24px;
}

.cs-section-body ol {
  list-style-type: decimal;
}

/* Two-col layout */
.cs-two-col {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 64px;
  align-items: start;
}

.cs-two-col--wide {
  grid-template-columns: 5fr 4fr;
}

/* Full-width image */
.cs-img-full {
  width: 100%;
  border-radius: 16px;
  overflow: hidden;
  background: #BABFAC;
}

.cs-img-full img {
  width: 100%;
  height: 100%;
  display: block;
  object-fit: cover;
}

.cs-img-full--tall {
  aspect-ratio: 4 / 3;
}

.cs-img-full--wide {
  aspect-ratio: 16 / 9;
}

.cs-img-full--quote {
  background: #fff;
}

.cs-img-full--quote img {
  object-fit: contain;
  height: auto;
}

/* Stacked consecutive images */
.cs-img-stack {
  margin-top: 32px;
}

/* Research image trio */
.cs-research-imgs {
  display: grid;
  grid-template-columns: 1fr 1fr 1fr;
  gap: 32px;
  margin-top: 48px;
}

@media (max-width: 768px) {
  .cs-research-imgs {
    grid-template-columns: 1fr;
  }
}

/* Image grid */
.cs-img-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  margin-top: 56px;
}

.cs-img-grid--3 {
  grid-template-columns: 1fr 1fr 1fr;
}

.cs-img-item {
  border-radius: 16px;
  overflow: hidden;
  background: #BABFAC;
  aspect-ratio: 3 / 4;
}

.cs-img-item img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

/* Problem / insight cards */
.cs-cards {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  margin-top: 48px;
}

.cs-card {
  background: #f8f8f6;
  border-radius: 16px;
  padding: 32px;
  border: 1px solid var(--color-border);
}

.cs-card-num {
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--color-muted);
  margin-bottom: 16px;
}

.cs-card-title {
  font-size: 17px;
  font-weight: 500;
  letter-spacing: -0.02em;
  color: #1c1c1a;
  margin-bottom: 12px;
}

.cs-card-body {
  font-size: 14px;
  line-height: 1.75;
  color: #666;
}

/* Quote block */
.cs-quote {
  border-left: 3px solid #57695B;
  padding: 8px 0 8px 32px;
  margin: 48px 0;
}

.cs-quote-text {
  font-size: clamp(20px, 2.5vw, 32px);
  font-weight: 300;
  letter-spacing: -0.025em;
  line-height: 1.35;
  color: #1c1c1a;
  margin-bottom: 16px;
}

.cs-quote-attr {
  font-size: 13px;
  color: var(--color-muted);
}

/* Next case study */
.cs-next {
  padding: calc(var(--section-py) * 0.65) 0 calc(var(--section-py) * 1.2);
}

.cs-next-label {
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--color-muted);
  margin-bottom: 24px;
}

/* Two-column image card variant */
.cs-next-card {
  margin-bottom: 0;
  display: grid;
  grid-template-columns: 1.1fr 1fr;
  gap: clamp(32px, 5vw, 64px);
  align-items: center;
}

.cs-next-card .project-img-wrap {
  aspect-ratio: 3 / 2;
}

.cs-next-card .project-meta {
  padding: 0;
}

.cs-next-card .project-title {
  font-size: clamp(24px, 3vw, 44px);
  font-weight: 300;
  line-height: 1.15;
}

@media (max-width: 640px) {
  .cs-next-card {
    grid-template-columns: 1fr;
    gap: 20px;
    align-items: start;
  }

  .cs-next-card .project-img-wrap {
    aspect-ratio: 16 / 10;
  }
}

/* Placeholder image style */
.cs-placeholder {
  width: 100%;
  height: 100%;
  min-height: 280px;
  background: linear-gradient(135deg, #BABFAC 0%, #9B9D85 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  color: rgba(255,255,255,0.7);
  font-size: 13px;
  font-family: var(--font-sans);
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

/* Prototype button */
.cs-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  margin-top: 36px;
  padding: 14px 28px;
  border-radius: 100px;
  background: #f0f0ee;
  border: 1.5px solid transparent;
  font-family: var(--font-sans);
  font-size: 15px;
  font-weight: 500;
  color: #1c1c1a;
  text-decoration: none;
  transition: background 0.25s, border-color 0.25s;
  overflow: hidden;
}

.cs-btn-arrow-wrap {
  position: relative;
  display: inline-block;
  width: 1em;
  height: 1em;
}

.cs-btn-arrow {
  position: absolute;
  top: 50%;
  left: 0;
  line-height: 1;
  display: inline-block;
  transition: opacity 0.35s cubic-bezier(0.4, 0, 0.2, 1), transform 0.35s cubic-bezier(0.4, 0, 0.2, 1);
}

.cs-btn-arrow--ne { opacity: 1; transform: translateY(-50%) rotate(-45deg); }
.cs-btn-arrow--e  { opacity: 0; transform: translateY(-50%) translateX(-4px); }

.cs-btn:hover {
  background: transparent;
  border-color: #1c1c1a;
}

.cs-btn:hover .cs-btn-arrow--ne {
  opacity: 0;
  transform: translateY(calc(-50% - 4px)) rotate(-45deg);
}

.cs-btn:hover .cs-btn-arrow--e {
  opacity: 1;
  transform: translateY(-50%) translateX(0);
}

/* ── Responsive ── */
@media (max-width: 960px) {
  .cs-stats {
    grid-template-columns: 1fr 1fr 1fr;
  }

  .cs-two-col,
  .cs-two-col--wide {
    grid-template-columns: 1fr;
    gap: 40px;
  }

  .cs-cards {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 640px) {
  .cs-stats {
    grid-template-columns: repeat(3, 1fr);
  }

  .cs-img-grid {
    grid-template-columns: 1fr;
  }

  .cs-img-grid--3 {
    grid-template-columns: 1fr;
  }

  .cs-cards {
    grid-template-columns: 1fr;
  }
}

/* ── Reading progress bar ── */
.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: #57695B;
  transform-origin: 0 50%;
  transform: scaleX(0);
  z-index: 200;
}