/* === CASE STUDY PAGES === */

.cs-nav {
  position: sticky;
  top: 0;
  z-index: 100;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1.25rem 3rem;
  background: rgba(244,244,244,0.88);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid rgba(10,10,10,0.07);
}
.cs-back {
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  color: var(--color-neutral-01);
  letter-spacing: 0.03em;
  transition: color 0.2s;
}
.cs-back:hover { color: var(--color-black); }
.cs-nav-name {
  font-family: var(--font-primary);
  font-size: 0.9rem;
  font-weight: var(--fw-medium);
  color: var(--color-black);
}

/* Header */
.cs-header {
  max-width: 760px;
  margin: 0 auto;
  padding: 4.5rem 2rem 3rem;
}
.cs-tag {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--color-neutral-01);
  margin-bottom: 1.25rem;
}
.cs-title {
  font-size: clamp(2rem, 5vw, 3.25rem);
  font-weight: var(--fw-semibold);
  line-height: 1.1;
  letter-spacing: -0.01em;
  color: var(--color-black);
  margin-bottom: 2.5rem;
}
.cs-metrics {
  display: flex;
  gap: 0;
  padding: 1.75rem 0;
  border-top: 1px solid rgba(10,10,10,0.08);
  border-bottom: 1px solid rgba(10,10,10,0.08);
}
.cs-metric {
  flex: 1;
  padding-right: 2rem;
  border-right: 1px solid rgba(10,10,10,0.08);
  margin-right: 2rem;
}
.cs-metric:last-child {
  border-right: none;
  margin-right: 0;
  padding-right: 0;
}
.cs-metric-value {
  display: block;
  font-size: 1.2rem;
  font-weight: var(--fw-semibold);
  color: var(--color-black);
  margin-bottom: 0.25rem;
  font-family: var(--font-primary);
}
.cs-metric-label {
  display: block;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: var(--color-neutral-01);
  letter-spacing: 0.04em;
}

/* Article */
.cs-article {
  max-width: 760px;
  margin: 0 auto;
  padding: 0 2rem 8rem;
}
.cs-section {
  padding: 3rem 0;
  border-bottom: 1px solid rgba(10,10,10,0.07);
}
.cs-section:last-child { border-bottom: none; }
.cs-section-label {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--color-neutral-01);
  margin-bottom: 1.5rem;
}
.cs-section p {
  font-size: 1.0625rem;
  line-height: 1.8;
  color: var(--color-dark);
  text-wrap: pretty;
  margin-bottom: 1.1rem;
}
.cs-section p:last-child { margin-bottom: 0; }
.cs-section h3 {
  font-size: 1rem;
  font-weight: var(--fw-semibold);
  color: var(--color-black);
  margin: 2rem 0 0.75rem;
}
.cs-section h3:first-child { margin-top: 0; }
.cs-section ul, .cs-section ol {
  padding-left: 1.4rem;
  margin-bottom: 1.1rem;
}
.cs-section li {
  font-size: 1.0625rem;
  line-height: 1.75;
  color: var(--color-dark);
  margin-bottom: 0.4rem;
}
.cs-section blockquote {
  border-left: 2px solid rgba(10,10,10,0.14);
  padding: 0.2rem 0 0.2rem 1.25rem;
  margin: 1.5rem 0;
}
.cs-section blockquote p {
  font-style: italic;
  color: var(--color-neutral-01);
  font-size: 1rem;
}
.cs-section strong { color: var(--color-black); font-weight: var(--fw-semibold); }

/* Patterns block */
.cs-pattern {
  background: rgba(10,10,10,0.03);
  border: 1px solid rgba(10,10,10,0.07);
  border-radius: var(--radius-lg);
  padding: 1.25rem 1.5rem;
  margin-bottom: 1rem;
}
.cs-pattern-title {
  font-size: 0.875rem;
  font-weight: var(--fw-semibold);
  color: var(--color-black);
  margin-bottom: 0.5rem;
  font-family: var(--font-primary);
}
.cs-pattern p {
  font-size: 0.9375rem !important;
  margin-bottom: 0 !important;
}

/* Table */
.cs-table {
  width: 100%;
  border-collapse: collapse;
  margin: 1.5rem 0;
  font-size: 0.9375rem;
}
.cs-table th {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-neutral-01);
  border-bottom: 1px solid rgba(10,10,10,0.12);
  padding: 0.5rem 1rem 0.5rem 0;
  text-align: left;
}
.cs-table td {
  padding: 0.75rem 1rem 0.75rem 0;
  border-bottom: 1px solid rgba(10,10,10,0.05);
  color: var(--color-dark);
  line-height: 1.5;
}

/* What changed two-col */
.cs-changed {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.5rem;
  margin-top: 0.5rem;
}
.cs-changed-block {
  background: rgba(10,10,10,0.03);
  border: 1px solid rgba(10,10,10,0.07);
  border-radius: var(--radius-lg);
  padding: 1.25rem 1.5rem;
}
.cs-changed-label {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-neutral-01);
  margin-bottom: 0.75rem;
}
.cs-changed-block p {
  font-size: 0.9375rem !important;
  margin-bottom: 0 !important;
}

/* Stated limitations. Quieter than body copy: it should read as a footnote the
   reader can skip, not as a disclaimer the page is apologising with. */
/* .cs-article p already sets colour, so a bare .cs-caveat loses the cascade */
.cs-article p.cs-caveat {
  font-size: 0.875rem !important;
  color: var(--color-neutral-01);
  border-left: 2px solid rgba(10,10,10,0.12);
  padding-left: 1rem;
  margin-top: 2rem !important;
}
.cs-article p.cs-caveat strong { color: var(--color-black); font-weight: var(--fw-medium); }

/* Mobile */
@media (max-width: 640px) {
  .cs-nav { padding: 1rem 1.25rem; }
  .cs-header { padding: 2.5rem 1.25rem 2rem; }
  .cs-article { padding: 0 1.25rem 5rem; }
  .cs-metrics { flex-direction: column; gap: 1.25rem; }
  .cs-metric { border-right: none; margin-right: 0; padding-right: 0; border-bottom: 1px solid rgba(10,10,10,0.08); padding-bottom: 1.25rem; }
  .cs-metric:last-child { border-bottom: none; padding-bottom: 0; }
  .cs-changed { grid-template-columns: 1fr; }
}