/* =============================================================
   CASE STUDY — Ads OS
   Layered on proposal.css. Same brand system, case-specific blocks.
   ============================================================= */

/* Current nav state */
.nav-links a.is-current { color: var(--purple); }
.nav-links a.is-current::after {
  content: ""; display: block; height: 2px; background: var(--yellow);
  margin-top: 4px;
}

/* ============ HERO ============ */
.cs-hero {
  background: var(--purple);
  color: var(--cream);
  padding: 96px 0 80px;
  position: relative;
  overflow: hidden;
}
.cs-hero::before {
  content: ""; position: absolute; inset: 0;
  background:
    radial-gradient(circle at 88% 12%, rgba(253, 204, 13, 0.18), transparent 42%),
    radial-gradient(circle at 4% 90%, rgba(253, 204, 13, 0.10), transparent 38%);
  pointer-events: none;
}
.cs-hero-inner { position: relative; }

.cs-hero-meta {
  display: flex; justify-content: space-between; align-items: baseline;
  padding-bottom: 24px;
  border-bottom: 1px solid rgba(253, 204, 13, 0.3);
  margin-bottom: 60px;
}
.cs-hero-meta .eyebrow { color: var(--yellow); }
.cs-hero-meta .eyebrow-dim { color: rgba(246, 239, 222, 0.6); font-family: var(--mono); font-size: 12px; letter-spacing: 0.14em; text-transform: uppercase; }

.cs-hero-title {
  font-family: var(--serif);
  font-size: clamp(64px, 10vw, 152px);
  line-height: 0.92;
  letter-spacing: -0.025em;
  font-weight: 400;
  margin: 0 0 32px;
  text-wrap: pretty;
}
.cs-hero-title em { color: var(--yellow); font-style: italic; }

.cs-hero-sub {
  font-family: var(--serif);
  font-style: italic;
  font-size: clamp(22px, 2.4vw, 32px);
  line-height: 1.35;
  color: rgba(246, 239, 222, 0.88);
  margin: 0 0 64px;
  max-width: 40ch;
}

.cs-stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1px;
  background: rgba(253, 204, 13, 0.18);
  border: 1px solid rgba(253, 204, 13, 0.18);
  border-radius: 8px;
  overflow: hidden;
}
.cs-stat {
  background: var(--purple);
  padding: 28px 24px;
  display: flex; flex-direction: column; gap: 10px;
}
.cs-stat-num {
  font-family: var(--serif);
  font-size: 72px;
  line-height: 0.95;
  font-weight: 400;
  letter-spacing: -0.02em;
  color: var(--yellow);
}
.cs-stat-num small { font-size: 0.6em; vertical-align: super; }
.cs-stat-label {
  font-family: var(--mono);
  font-size: 13px;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  line-height: 1.5;
}
.cs-stat-label small {
  display: block;
  font-size: 11px;
  text-transform: none;
  letter-spacing: 0.08em;
  opacity: 0.6;
  margin-top: 2px;
}

@media (max-width: 900px) { .cs-stats { grid-template-columns: 1fr 1fr; } }

/* ============ CLIENT SECTIONS ============ */
.cs-client { padding: 120px 0; }
.cs-client--01 { background: var(--bg); }
.cs-client--02 { background: var(--purple-deep); color: var(--cream); }
.cs-client--03 { background: var(--yellow); color: var(--purple-ink); }

.cs-client-head { margin-bottom: 56px; max-width: 880px; }
.cs-client-num {
  display: inline-block;
  font-family: var(--mono);
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.18em;
  padding-bottom: 16px;
  margin-bottom: 20px;
  border-bottom: 1px solid currentColor;
}
.cs-client--01 .cs-client-num { color: var(--purple); }
.cs-client--02 .cs-client-num { color: var(--yellow); }
.cs-client--03 .cs-client-num { color: var(--purple); }
.cs-client-title {
  font-family: var(--serif);
  font-size: clamp(56px, 8vw, 112px);
  line-height: 0.95;
  letter-spacing: -0.025em;
  font-weight: 400;
  margin-bottom: 14px;
}
.cs-client-sub {
  font-family: var(--mono);
  font-size: 14px;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  margin: 0;
  opacity: 0.7;
}

/* Metric row */
.cs-metric-row {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 1px;
  background: rgba(26, 10, 46, 0.15);
  border: 1px solid rgba(26, 10, 46, 0.15);
  border-radius: 8px;
  overflow: hidden;
  margin-bottom: 56px;
}
.cs-client--02 .cs-metric-row { background: rgba(253, 204, 13, 0.2); border-color: rgba(253, 204, 13, 0.2); }
.cs-metric {
  background: var(--bg);
  padding: 26px 22px;
  display: flex; flex-direction: column; gap: 8px;
}
.cs-client--02 .cs-metric { background: var(--purple-deep); }
.cs-client--03 .cs-metric { background: var(--yellow); }
.cs-metric-num {
  font-family: var(--serif);
  font-size: 56px;
  line-height: 0.95;
  font-weight: 400;
  letter-spacing: -0.02em;
}
.cs-client--01 .cs-metric-num { color: var(--purple); }
.cs-client--02 .cs-metric-num { color: var(--yellow); }
.cs-client--03 .cs-metric-num { color: var(--purple); }
.cs-metric-label {
  font-family: var(--mono);
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.14em;
  opacity: 0.78;
}

@media (max-width: 900px) { .cs-metric-row { grid-template-columns: 1fr 1fr; } }

/* Ad-level table */
.cs-table {
  border: 1px solid rgba(26, 10, 46, 0.15);
  border-radius: 8px;
  overflow: hidden;
  margin-bottom: 64px;
  font-size: 15px;
}
.cs-table-head, .cs-table-row {
  display: grid;
  grid-template-columns: 2.2fr 0.8fr 0.8fr 0.8fr 1.2fr;
  align-items: center;
  padding: 18px 24px;
  gap: 16px;
}
.cs-table-head {
  background: var(--purple);
  color: var(--cream);
  font-family: var(--mono);
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.14em;
}
.cs-table-row { background: var(--bg); border-top: 1px solid rgba(26, 10, 46, 0.1); }
.cs-table-row--win { background: rgba(253, 204, 13, 0.18); }
.cs-table-row--win b { color: var(--purple); }
.cs-tag {
  display: inline-block;
  background: var(--yellow);
  color: var(--purple-ink);
  font-family: var(--mono);
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 0.14em;
  padding: 4px 12px;
  border-radius: 999px;
  font-weight: 600;
  justify-self: start;
}

@media (max-width: 800px) {
  .cs-table-head { display: none; }
  .cs-table-row { grid-template-columns: 1fr 1fr; gap: 8px 16px; }
}

/* Two-campaign cards (Ever After) */
.cs-two-camp {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
  margin-bottom: 24px;
}
.cs-camp {
  background: rgba(253, 204, 13, 0.08);
  border: 1px solid rgba(253, 204, 13, 0.2);
  border-radius: 8px;
  padding: 32px 28px;
  display: flex; flex-direction: column; gap: 18px;
}
.cs-camp-eyebrow {
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--yellow);
}
.cs-camp-title {
  font-family: var(--serif);
  font-size: 32px;
  font-weight: 400;
  font-style: italic;
  line-height: 1.1;
  letter-spacing: -0.01em;
}
.cs-camp-stats { display: grid; grid-template-columns: repeat(5, 1fr); gap: 12px; padding-top: 16px; border-top: 1px solid rgba(253, 204, 13, 0.2); }
.cs-camp-stats > div { display: flex; flex-direction: column; gap: 4px; }
.cs-camp-stats span {
  font-family: var(--serif);
  font-size: 26px;
  color: var(--yellow);
  line-height: 1;
  letter-spacing: -0.01em;
}
.cs-camp-stats small {
  font-family: var(--mono);
  font-size: 10px;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  opacity: 0.6;
}

@media (max-width: 800px) { .cs-two-camp { grid-template-columns: 1fr; } .cs-camp-stats { grid-template-columns: repeat(3, 1fr); } }

.cs-totals {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 28px;
  padding: 20px 28px;
  background: var(--yellow);
  color: var(--purple-ink);
  border-radius: 6px;
  font-size: 15px;
  margin-bottom: 64px;
  font-family: var(--mono);
  letter-spacing: 0.04em;
}
.cs-totals .eyebrow-yellow { color: var(--purple-deep); }
.cs-totals b { font-family: var(--sans); font-size: 22px; font-weight: 600; }

/* Winning creative blocks */
.cs-winning { margin-top: 16px; }
.cs-winning-head { margin-bottom: 32px; }
.cs-winning-head .eyebrow-yellow { color: var(--yellow); }
.cs-client--01 .cs-winning-head .eyebrow-yellow { color: var(--purple); }
.cs-client--03 .cs-winning-head .eyebrow-yellow { color: var(--purple); }
.cs-winning-title {
  font-family: var(--serif);
  font-size: clamp(40px, 5vw, 64px);
  line-height: 1;
  letter-spacing: -0.02em;
  font-weight: 400;
  margin-top: 12px;
  text-wrap: pretty;
}
.cs-winning-title em { font-style: italic; }
.cs-client--01 .cs-winning-title em { color: var(--purple); }
.cs-client--02 .cs-winning-title em { color: var(--yellow); }

.cs-winning-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
}
.cs-winning-card {
  background: var(--cream);
  color: var(--ink);
  border-radius: 8px;
  padding: 28px;
  display: flex; flex-direction: column; gap: 12px;
}
.cs-client--03 .cs-winning-card { background: rgba(255,255,255,0.5); }
.cs-winning-card--result {
  background: var(--ink);
  color: var(--cream);
}
.cs-winning-card--result strong { color: var(--yellow); font-weight: 600; }
.cs-winning-tag {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--purple);
}
.cs-winning-card--result .cs-winning-tag { color: var(--yellow); }
.cs-winning-card p { font-size: 15px; line-height: 1.55; margin: 0; }

@media (max-width: 800px) { .cs-winning-grid { grid-template-columns: 1fr; } }

/* Strategy block (Simply Home) */
.cs-strategy {
  background: rgba(105, 53, 156, 0.08);
  border-left: 4px solid var(--purple);
  padding: 24px 28px;
  border-radius: 0 8px 8px 0;
  display: flex; flex-direction: column; gap: 10px;
}
.cs-strategy .eyebrow-yellow { color: var(--purple); }
.cs-strategy p { font-size: 17px; line-height: 1.6; margin: 0; }

/* ============ APRIL ============ */
.cs-april {
  background: var(--bg);
  padding: 120px 0;
}
.cs-april-lede {
  font-size: 20px;
  line-height: 1.55;
  max-width: 60ch;
  margin: 0 0 56px;
  opacity: 0.88;
}

.cs-april-stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1px;
  background: rgba(26, 10, 46, 0.15);
  border: 1px solid rgba(26, 10, 46, 0.15);
  border-radius: 8px;
  overflow: hidden;
  margin-bottom: 48px;
}
.cs-april-stat {
  background: var(--bg);
  padding: 28px 24px;
  display: flex; flex-direction: column; gap: 10px;
}
.cs-april-num {
  font-family: var(--serif);
  font-size: 56px;
  line-height: 0.95;
  letter-spacing: -0.02em;
  color: var(--purple);
}
.cs-april-label {
  font-family: var(--mono);
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.14em;
}
.cs-april-label small {
  display: block;
  font-size: 11px;
  text-transform: none;
  letter-spacing: 0.06em;
  opacity: 0.6;
  margin-top: 2px;
}

@media (max-width: 900px) { .cs-april-stats { grid-template-columns: 1fr 1fr; } }

.cs-april-split { display: grid; grid-template-columns: 1fr 1fr; gap: 24px; }
.cs-april-card {
  background: var(--purple);
  color: var(--cream);
  padding: 32px 30px;
  border-radius: 8px;
  display: flex; flex-direction: column; gap: 16px;
}
.cs-april-card:nth-child(2) { background: var(--purple-deep); }
.cs-april-tag {
  font-family: var(--mono);
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.16em;
  color: var(--yellow);
}
.cs-april-card h4 {
  font-family: var(--serif);
  font-size: 28px;
  line-height: 1.15;
  font-weight: 400;
  font-style: italic;
  letter-spacing: -0.01em;
}
.cs-april-card ul { display: flex; flex-direction: column; gap: 8px; font-size: 14px; opacity: 0.88; }
.cs-april-card li { padding-left: 20px; position: relative; line-height: 1.5; }
.cs-april-card li::before { content: "→"; position: absolute; left: 0; color: var(--yellow); }

@media (max-width: 800px) { .cs-april-split { grid-template-columns: 1fr; } }

/* ============ FORMULA ============ */
.cs-formula {
  background: var(--ink);
  color: var(--cream);
  padding: 120px 0;
}
.cs-formula .section-display em { color: var(--yellow); }

.cs-formula-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
  margin-top: 48px;
}
.cs-f-card {
  background: rgba(246, 239, 222, 0.05);
  border: 1px solid rgba(246, 239, 222, 0.12);
  border-radius: 8px;
  padding: 32px 28px;
  display: flex; flex-direction: column; gap: 14px;
  transition: background 0.18s, border-color 0.18s;
}
.cs-f-card:hover { background: rgba(253, 204, 13, 0.08); border-color: rgba(253, 204, 13, 0.3); }
.cs-f-num {
  font-family: var(--serif);
  font-style: italic;
  font-size: 56px;
  line-height: 0.9;
  color: var(--yellow);
}
.cs-f-card h3 {
  font-family: var(--serif);
  font-size: 30px;
  font-weight: 400;
  line-height: 1.05;
  letter-spacing: -0.01em;
}
.cs-f-card p { font-size: 15px; line-height: 1.55; margin: 0; opacity: 0.85; }

@media (max-width: 900px) { .cs-formula-grid { grid-template-columns: 1fr; } }