/* ============================================================
   CASE STUDY  —  shared styles for all case study sub-pages
   ============================================================ */

/* ── Back / breadcrumb link ───────────────────────────── */
.cs-back {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-ui);
  font-size: 0.6875rem;
  font-weight: 500;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--ink-2);
  transition: color 0.2s, opacity 0.2s;
}
.cs-back svg { width: 16px; height: 16px; flex-shrink: 0; }
.cs-back:hover { color: var(--ink); }

/* ── Hero ─────────────────────────────────────────────── */
.cs-hero {
  padding: calc(var(--pad-y) + 4.5rem) var(--pad-x) var(--pad-y);
  max-width: var(--max-w);
  margin: 0 auto;
  border-bottom: 1px solid var(--border);
}

.cs-tags {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.5rem;
  font-family: var(--font-ui);
  font-size: 0.6rem;
  font-weight: 500;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink-2);
  margin-top: 2rem;
  margin-bottom: 1.75rem;
}

.cs-headline {
  font-family: var(--font-display);
  font-size: clamp(3.25rem, 8.5vw, 8rem);
  font-weight: 300;
  line-height: 1.0;
  letter-spacing: -0.02em;
  margin-bottom: 3.5rem;
}
.cs-headline em {
  font-style: italic;
  color: var(--accent);
}

/* Metadata row */
.cs-meta {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 2.5rem;
  padding-top: 2rem;
  border-top: 1px solid var(--border);
}
.cs-meta-label {
  display: block;
  font-family: var(--font-ui);
  font-size: 0.575rem;
  font-weight: 500;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--ink-2);
  margin-bottom: 0.6rem;
}
.cs-meta-value {
  display: block;
  font-size: 0.875rem;
  line-height: 1.6;
  color: var(--ink);
}

/* ── Intro / Overview ─────────────────────────────────── */
.cs-intro {
  padding: clamp(3.5rem, 8vh, 5.5rem) var(--pad-x);
  border-bottom: 1px solid var(--border);
}
.cs-intro-inner {
  max-width: var(--max-w);
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: clamp(2rem, 6vw, 6rem);
  align-items: start;
}
.cs-lead {
  font-family: var(--font-display);
  font-size: clamp(1.35rem, 2.4vw, 1.9rem);
  font-weight: 400;
  line-height: 1.4;
  color: var(--ink);
}
.cs-body {
  font-size: clamp(0.9rem, 1.1vw, 1rem);
  line-height: 1.8;
  color: var(--ink-2);
}
.cs-body + .cs-body { margin-top: 1.25rem; }

/* ── Case Study Sections ──────────────────────────────── */
.cs-section {
  padding: clamp(4rem, 9vh, 7rem) var(--pad-x);
  border-bottom: 1px solid var(--border);
}
.cs-section--alt { background: var(--surface); }

.cs-section-inner {
  max-width: var(--max-w);
  margin: 0 auto;
}

.cs-section-header {
  display: flex;
  align-items: baseline;
  gap: 1.25rem;
  padding-bottom: 1.5rem;
  border-bottom: 1px solid var(--border);
  margin-bottom: clamp(2.5rem, 5vh, 4rem);
}

.cs-section-body { max-width: 860px; }

.cs-subhead {
  font-family: var(--font-display);
  font-size: clamp(1.2rem, 2vw, 1.65rem);
  font-weight: 400;
  font-style: italic;
  color: var(--ink);
  margin-top: 2.75rem;
  margin-bottom: 0.75rem;
}
.cs-subhead:first-child { margin-top: 0; }

/* ── Callouts — challenge items ───────────────────────── */
.cs-callouts {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
  margin-top: 2.75rem;
}
.cs-callout {
  padding: 1.75rem 1.5rem;
  background: var(--bg);
  border-top: 2px solid var(--accent);
}
[data-theme] .cs-callout { background: var(--surface); }
.cs-section--alt .cs-callout { background: var(--bg); }

.cs-callout-label {
  display: block;
  font-family: var(--font-ui);
  font-size: 0.575rem;
  font-weight: 500;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 0.85rem;
}
.cs-callout p {
  font-size: 0.9rem;
  line-height: 1.7;
  color: var(--ink-2);
  margin: 0;
}

/* ── Steps — ordered process list ────────────────────── */
.cs-steps {
  list-style: none;
  counter-reset: steps;
  margin-top: 2.25rem;
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}
.cs-steps li {
  counter-increment: steps;
  display: grid;
  grid-template-columns: 3rem 1fr;
  gap: 0.75rem;
  align-items: start;
  font-size: 0.95rem;
  line-height: 1.7;
  color: var(--ink-2);
}
.cs-steps li::before {
  content: counter(steps, decimal-leading-zero);
  font-family: var(--font-display);
  font-size: 1.75rem;
  font-weight: 300;
  color: var(--ink);
  opacity: 0.25;
  line-height: 1.1;
}

/* ── Goals table ─────────────────────────────────────── */
.cs-table {
  width: 100%;
  border-collapse: collapse;
  margin-top: 1.5rem;
  font-size: 0.875rem;
}
.cs-table th {
  font-family: var(--font-ui);
  font-size: 0.575rem;
  font-weight: 500;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--ink-2);
  text-align: left;
  padding: 0.75rem 1rem 0.75rem 0;
  border-bottom: 1px solid var(--border);
}
.cs-table td {
  padding: 0.9rem 1rem 0.9rem 0;
  border-bottom: 1px solid var(--border);
  color: var(--ink-2);
  line-height: 1.5;
}
.cs-table td:last-child {
  font-family: var(--font-ui);
  font-size: 0.8rem;
  font-weight: 500;
  letter-spacing: 0.04em;
  color: var(--ink);
}
.cs-table tr:last-child td { border-bottom: none; }

/* ── Surface list — before/after screens ─────────────── */
.cs-surfaces {
  display: flex;
  flex-direction: column;
  gap: 0;
  margin-top: 2.75rem;
  border-top: 1px solid var(--border);
}
.cs-surface {
  display: grid;
  grid-template-columns: 12rem 1fr;
  gap: 2rem;
  align-items: start;
  padding: 1.5rem 0;
  border-bottom: 1px solid var(--border);
}
.cs-surface-label {
  display: flex;
  align-items: baseline;
  gap: 0.75rem;
  font-family: var(--font-ui);
  font-size: 0.75rem;
  font-weight: 500;
  letter-spacing: 0.06em;
  color: var(--ink);
}
.cs-surface-num {
  font-family: var(--font-display);
  font-size: 1.5rem;
  font-weight: 300;
  color: var(--accent);
  line-height: 1;
  flex-shrink: 0;
}
.cs-surface p {
  font-size: 0.9rem;
  line-height: 1.7;
  color: var(--ink-2);
  margin: 0;
}

/* ── Outcomes — impact metrics grid ──────────────────── */
.cs-outcomes {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.5rem;
  margin-top: 2.75rem;
}
.cs-outcome {
  display: flex;
  align-items: flex-start;
  gap: 1.25rem;
  padding: 2rem 1.75rem;
  border: 1px solid var(--border);
}
.cs-outcome-mark {
  font-family: var(--font-display);
  font-size: 2.25rem;
  font-weight: 300;
  color: var(--accent);
  line-height: 1;
  flex-shrink: 0;
  width: 2rem;
  text-align: center;
}
.cs-outcome strong {
  display: block;
  font-family: var(--font-ui);
  font-size: 0.6rem;
  font-weight: 500;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink);
  margin-bottom: 0.6rem;
}
.cs-outcome p {
  font-size: 0.9rem;
  line-height: 1.7;
  color: var(--ink-2);
  margin: 0;
}

/* ── Bottom navigation ────────────────────────────────── */
.cs-nav-bottom {
  padding: clamp(3rem, 6vh, 4.5rem) var(--pad-x);
  max-width: var(--max-w);
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.cs-nav-back,
.cs-nav-next {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-ui);
  font-size: 0.6875rem;
  font-weight: 500;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--ink-2);
  transition: color 0.2s;
}
.cs-nav-back:hover,
.cs-nav-next:hover { color: var(--ink); }
.cs-nav-back svg,
.cs-nav-next svg { width: 16px; height: 16px; flex-shrink: 0; }


/* ════════════════════════════════════════════════════════
   RESPONSIVE
   ════════════════════════════════════════════════════════ */
@media (max-width: 960px) {
  .cs-intro-inner { grid-template-columns: 1fr; gap: 2rem; }
  .cs-meta { grid-template-columns: repeat(2, 1fr); gap: 1.75rem; }
  .cs-callouts { grid-template-columns: 1fr; }
  .cs-outcomes { grid-template-columns: 1fr; }
  .cs-surface { grid-template-columns: 1fr; gap: 0.5rem; }
}

@media (max-width: 600px) {
  .cs-meta { grid-template-columns: 1fr 1fr; gap: 1.5rem; }
  .cs-headline { font-size: clamp(2.75rem, 13vw, 4rem); }
  .cs-steps li { grid-template-columns: 2rem 1fr; }
}


/* ════════════════════════════════════════════════════════
   THEME OVERRIDES
   ════════════════════════════════════════════════════════ */

/* Tron */
[data-theme="tron"] .cs-back,
[data-theme="tron"] .cs-nav-back,
[data-theme="tron"] .cs-nav-next { color: rgba(0, 229, 255, 0.55); }
[data-theme="tron"] .cs-back:hover,
[data-theme="tron"] .cs-nav-back:hover,
[data-theme="tron"] .cs-nav-next:hover { color: var(--accent); }
[data-theme="tron"] .cs-callout { border-top-color: var(--accent); }
[data-theme="tron"] .cs-outcome { border-color: var(--border); }

/* 16-bit */
[data-theme="16bit"] .cs-headline { font-size: clamp(1.1rem, 3.5vw, 2.2rem); line-height: 1.9; }
[data-theme="16bit"] .cs-lead { font-size: clamp(0.55rem, 1.1vw, 0.8rem); line-height: 2.4; }
[data-theme="16bit"] .cs-body { font-size: 0.48rem; line-height: 2.4; }
[data-theme="16bit"] .cs-subhead { font-size: 0.65rem; line-height: 2; }
[data-theme="16bit"] .cs-callout-label,
[data-theme="16bit"] .cs-meta-label,
[data-theme="16bit"] .cs-outcome strong { font-size: 0.38rem; }
[data-theme="16bit"] .cs-meta-value { font-size: 0.45rem; line-height: 2; }
[data-theme="16bit"] .cs-callout p,
[data-theme="16bit"] .cs-outcome p { font-size: 0.42rem; line-height: 2.2; }
[data-theme="16bit"] .cs-callout { border-top: 3px solid var(--accent); }
[data-theme="16bit"] .cs-outcome { border: 2px solid var(--accent); }

/* Retro Future */
[data-theme="retro"] .cs-headline { font-weight: 100; text-transform: uppercase; letter-spacing: -0.01em; }
[data-theme="retro"] .cs-headline em { font-style: italic; text-transform: none; }
[data-theme="retro"] .cs-subhead { font-weight: 100; }
[data-theme="retro"] .cs-meta-label,
[data-theme="retro"] .cs-callout-label,
[data-theme="retro"] .cs-outcome strong { letter-spacing: 0.2em; }

/* Win95 */
[data-theme="win95"] .cs-headline { font-size: clamp(1.4rem, 4vw, 3rem); font-weight: bold; letter-spacing: 0; line-height: 1.3; color: #000080; }
[data-theme="win95"] .cs-headline em { font-style: normal; color: #000080; }
[data-theme="win95"] .cs-lead { font-size: clamp(0.8rem, 1.2vw, 1rem); line-height: 1.65; }
[data-theme="win95"] .cs-body { font-size: 0.8rem; line-height: 1.65; }
[data-theme="win95"] .cs-subhead { font-size: 0.9rem; font-style: normal; font-weight: bold; }
[data-theme="win95"] .cs-callout {
  border-top: none;
  border-top: 2px solid #FFFFFF;
  border-left: 2px solid #FFFFFF;
  border-right: 2px solid #808080;
  border-bottom: 2px solid #808080;
}
[data-theme="win95"] .cs-outcome {
  border-top: 2px solid #FFFFFF;
  border-left: 2px solid #FFFFFF;
  border-right: 2px solid #808080;
  border-bottom: 2px solid #808080;
}
[data-theme="win95"] .cs-callout-label,
[data-theme="win95"] .cs-meta-label,
[data-theme="win95"] .cs-outcome strong { font-size: 0.65rem; letter-spacing: 0; text-transform: none; font-weight: bold; color: #000080; }
[data-theme="win95"] .cs-meta-value,
[data-theme="win95"] .cs-callout p,
[data-theme="win95"] .cs-outcome p,
[data-theme="win95"] .cs-steps li { font-size: 0.75rem; line-height: 1.65; }
[data-theme="win95"] .cs-surface { grid-template-columns: 1fr; }
[data-theme="win95"] .cs-table th,
[data-theme="win95"] .cs-table td { font-size: 0.7rem; }

/* 16-bit additions */
[data-theme="16bit"] .cs-surface p { font-size: 0.42rem; line-height: 2.2; }
[data-theme="16bit"] .cs-table th { font-size: 0.38rem; }
[data-theme="16bit"] .cs-table td { font-size: 0.42rem; }