/* =====================================================================
   Daffa Porto — Case study pages
   case-study.css

   Long-form, single-column reading layout on daylight paper. Uses the
   tokens from colors_and_type.css; no scroll engine.
   ===================================================================== */

* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }

body {
  background:
    linear-gradient(to bottom, #DCEEF7 0, var(--paper) 520px) no-repeat,
    var(--paper);
  color: var(--ink);
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

a { color: inherit; }

.cs-nav {
  max-width: 1040px;
  margin: 0 auto;
  padding: 24px 32px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}
.cs-nav .brand {
  font-family: var(--font-serif);
  font-style: italic;
  font-size: 22px;
  letter-spacing: -0.02em;
  text-decoration: none;
}
.cs-nav .brand .d { display: inline-block; width: 7px; height: 7px; border-radius: 50%; background: var(--signal); margin-left: 3px; }
.cs-nav .back,
.cs-kicker,
.cs-meta .lab,
.cs-stat .e,
.cs-foot {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}
.cs-nav .back { color: var(--ink-3); text-decoration: none; }
.cs-nav .back:hover { color: var(--ink); }

.cs-main {
  max-width: 1040px;
  margin: 0 auto;
  padding: 48px 32px 96px;
}

/* --- Header --- */
.cs-kicker { color: var(--ink-3); margin-bottom: 18px; display: flex; align-items: center; gap: 10px; }
.cs-kicker .pip { width: 7px; height: 7px; border-radius: 50%; background: var(--ok); }

.cs-title {
  font-family: var(--font-serif);
  font-weight: 400;
  font-size: clamp(48px, 8vw, 96px);
  line-height: 1;
  letter-spacing: -0.02em;
  margin: 0 0 24px;
}
.cs-title em { font-style: italic; }
.cs-title .accent { color: var(--signal); }

.cs-lede {
  font-size: clamp(18px, 2.2vw, 22px);
  line-height: 1.5;
  color: var(--ink-2);
  max-width: 46ch;
  margin: 0 0 40px;
}

.cs-meta {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 18px 28px;
  padding: 22px 0;
  border-top: 1px solid var(--rule-strong);
  border-bottom: 1px solid var(--rule-strong);
}
.cs-meta .lab { color: var(--ink-4); font-size: 10px; margin-bottom: 4px; }
.cs-meta .val { font-size: 14.5px; font-weight: 500; }

.cs-note {
  margin: 20px 0 0;
  font-size: 13.5px;
  color: var(--ink-3);
  display: flex;
  gap: 10px;
  align-items: baseline;
}
.cs-note::before { content: "NDA"; font-family: var(--font-mono); font-size: 10px; letter-spacing: 0.12em; padding: 2px 7px; border-radius: 999px; background: var(--signal-wash); color: var(--signal-ink); flex-shrink: 0; }

/* --- Stat strip --- */
.cs-stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1px;
  margin: 56px 0 0;
  background: var(--rule-strong);
  border: 1px solid var(--rule-strong);
  border-radius: 12px;
  overflow: hidden;
}
.cs-stat { background: var(--card); padding: 20px; }
.cs-stat .e { font-size: 10px; color: var(--ink-3); margin-bottom: 8px; }
.cs-stat .v { font-size: 30px; font-weight: 500; letter-spacing: -0.02em; line-height: 1.1; font-variant-numeric: tabular-nums; }
.cs-stat .v s { display: block; font-size: 14px; font-weight: 400; color: var(--ink-4); letter-spacing: 0; font-family: var(--font-mono); margin-bottom: 2px; }
.cs-stat .d { font-size: 13px; color: var(--ink-3); margin-top: 6px; line-height: 1.4; }

/* --- Body sections --- */
.cs-section {
  display: grid;
  grid-template-columns: 220px 1fr;
  gap: 40px;
  padding: 56px 0 0;
}
.cs-section > h2 {
  font-family: var(--font-serif);
  font-weight: 400;
  font-size: 32px;
  line-height: 1.1;
  margin: 0;
  letter-spacing: -0.01em;
}
.cs-section > h2 em { font-style: italic; }
.cs-body > :first-child { margin-top: 0; }
.cs-body h3 {
  font-size: 17px;
  font-weight: 600;
  margin: 32px 0 8px;
}
.cs-body p { color: var(--ink-2); margin: 0 0 14px; max-width: 68ch; }
.cs-body ul { margin: 0 0 14px; padding-left: 20px; color: var(--ink-2); max-width: 68ch; }
.cs-body li { margin-bottom: 6px; }
.cs-body li::marker { color: var(--ink-4); }
.cs-body strong { color: var(--ink); font-weight: 600; }
.cs-body code { font-family: var(--font-mono); font-size: 0.88em; background: var(--rule); padding: 1px 5px; border-radius: 4px; }

.cs-modules {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1px;
  background: var(--rule-strong);
  border: 1px solid var(--rule-strong);
  border-radius: 10px;
  overflow: hidden;
  margin: 20px 0 18px;
}
.cs-modules div { background: var(--card); padding: 14px 16px; font-size: 14px; color: var(--ink-2); line-height: 1.5; }
.cs-modules b { display: block; color: var(--ink); font-weight: 600; margin-bottom: 2px; }

.cs-chips { display: flex; flex-wrap: wrap; gap: 8px; }
.cs-chips span {
  font-family: var(--font-mono);
  font-size: 12px;
  padding: 5px 11px;
  border-radius: 999px;
  border: 1px solid var(--rule-strong);
  background: var(--card);
  color: var(--ink-2);
}

/* --- Footer --- */
.cs-foot {
  max-width: 1040px;
  margin: 0 auto;
  padding: 32px 32px 56px;
  border-top: 1px solid var(--rule-strong);
  display: flex;
  justify-content: space-between;
  gap: 18px;
  flex-wrap: wrap;
  color: var(--ink-3);
}
.cs-foot a { text-decoration: none; }
.cs-foot a:hover { color: var(--ink); }

@media (max-width: 880px) {
  .cs-meta,
  .cs-stats { grid-template-columns: 1fr 1fr; }
  .cs-section { grid-template-columns: 1fr; gap: 16px; padding-top: 48px; }
}

@media (max-width: 560px) {
  .cs-nav, .cs-main, .cs-foot { padding-left: 16px; padding-right: 16px; }
  .cs-main { padding-top: 24px; }
  .cs-modules { grid-template-columns: 1fr; }
  .cs-stat { padding: 16px; }
  .cs-stat .v { font-size: 26px; }
}