/* ============================================================
   THRIVE · UX Case Study
   Design language: a real case file. Manila folder tabs mark
   each stage of the process, a case-number stamp anchors the
   hero, and a "file thickness" bar tracks reading progress.
   ============================================================ */

@import url('https://fonts.googleapis.com/css2?family=Source+Serif+4:ital,opsz,wght@0,8..60,400;0,8..60,600;0,8..60,700;1,8..60,500&family=Inter:wght@400;500;600;700&family=JetBrains+Mono:wght@400;500;600&display=swap');

:root {
  /* Color */
  --paper:      #F1F3EE;
  --paper-deep: #E8EBE2;
  --card:       #FBFBF8;
  --ink:        #1E2A26;
  --ink-soft:   #4B5A54;
  --ink-faint:  #8B9690;
  --teal:       #3F6659;
  --teal-deep:  #2B4A40;
  --brick:      #B5482F;
  --brick-soft: #E8DACF;
  --manila:     #E9E1CC;
  --manila-line:#C9B98F;
  --line:       #D3D8CB;

  /* Type */
  --display: 'Source Serif 4', Georgia, serif;
  --body: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  --mono: 'JetBrains Mono', 'SFMono-Regular', Consolas, monospace;

  --wrap: 1180px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  * { animation-duration: 0.01ms !important; animation-iteration-count: 1 !important; transition-duration: 0.01ms !important; }
}

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--body);
  font-size: 17px;
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
}

img { max-width: 100%; display: block; }

a { color: inherit; }

h1, h2, h3 { font-family: var(--display); color: var(--ink); margin: 0; }

::selection { background: var(--brick); color: var(--card); }

:focus-visible {
  outline: 2px solid var(--brick);
  outline-offset: 3px;
  border-radius: 2px;
}

/* ---------- progress bar (file thickness) ---------- */
.progress {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: 4px;
  background: var(--paper-deep);
  z-index: 100;
}
.progress span {
  display: block;
  height: 100%;
  width: 0%;
  background: linear-gradient(90deg, var(--teal), var(--brick));
  transition: width 0.08s linear;
}

/* ---------- header / nav ---------- */
.site-header {
  position: sticky;
  top: 4px;
  z-index: 90;
  background: rgba(241, 243, 238, 0.92);
  backdrop-filter: blur(6px);
  border-bottom: 1px solid var(--line);
}
.header-inner {
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 14px 32px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}
.wordmark {
  font-family: var(--mono);
  font-weight: 600;
  font-size: 14px;
  letter-spacing: 0.12em;
  text-decoration: none;
  color: var(--ink);
  border: 1px solid var(--ink);
  padding: 4px 9px;
  border-radius: 3px;
  flex: none;
}
.site-header nav {
  display: flex;
  gap: 4px;
  overflow-x: auto;
  scrollbar-width: none;
}
.site-header nav::-webkit-scrollbar { display: none; }
.site-header nav a {
  flex: none;
  text-decoration: none;
  font-size: 13.5px;
  color: var(--ink-soft);
  padding: 7px 12px;
  border-radius: 5px;
  white-space: nowrap;
  transition: background 0.15s, color 0.15s;
}
.site-header nav a:hover { color: var(--ink); background: var(--paper-deep); }
.site-header nav a[aria-current="true"] {
  color: var(--card);
  background: var(--teal);
}

/* ---------- layout helpers ---------- */
main { max-width: var(--wrap); margin: 0 auto; padding: 0 32px; }

.section {
  padding: 88px 0;
  border-top: 1px solid var(--line);
}
.section:first-of-type { border-top: none; }

/* case-file tab kicker */
.section-kicker {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--ink-soft);
  background: var(--manila);
  border: 1px solid var(--manila-line);
  border-bottom: none;
  padding: 7px 16px 9px;
  border-radius: 7px 7px 0 0;
  margin-bottom: -1px;
  position: relative;
  transform: rotate(-0.4deg);
}
.section:nth-of-type(even) .section-kicker { transform: rotate(0.4deg); }

.section-heading {
  border: 1px solid var(--manila-line);
  background: var(--card);
  padding: 28px 30px 8px;
  border-radius: 0 10px 10px 10px;
  margin-bottom: 40px;
}
.section-heading h2 {
  font-size: clamp(1.5rem, 2.6vw, 2.1rem);
  font-weight: 600;
  line-height: 1.25;
  max-width: 32ch;
}
.section-heading p {
  color: var(--ink-soft);
  max-width: 62ch;
  font-size: 16px;
  margin-top: 14px;
  padding-bottom: 22px;
}

/* reveal on scroll */
.reveal { opacity: 0; transform: translateY(14px); transition: opacity 0.6s ease, transform 0.6s ease; }
.reveal.is-visible { opacity: 1; transform: translateY(0); }

/* ---------- hero ---------- */
.hero {
  padding: 56px 0 64px;
  display: grid;
  grid-template-columns: 1.05fr 0.95fr;
  gap: 48px;
  align-items: center;
}
.hero-copy { position: relative; }
.eyebrow {
  font-family: var(--mono);
  font-size: 12.5px;
  letter-spacing: 0.1em;
  color: var(--brick);
  margin: 0 0 10px;
  text-transform: uppercase;
}
.hero h1 {
  font-size: clamp(2.6rem, 6vw, 4.2rem);
  font-weight: 700;
  letter-spacing: -0.01em;
  line-height: 0.95;
}
.hero h2 {
  font-family: var(--body);
  font-weight: 600;
  font-size: clamp(1.05rem, 2vw, 1.3rem);
  color: var(--ink-soft);
  margin-top: 14px;
  max-width: 34ch;
}
.hero-intro {
  margin-top: 20px;
  max-width: 52ch;
  color: var(--ink-soft);
  font-size: 16px;
}

.meta-grid {
  margin-top: 32px;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  border: 1px solid var(--line);
  border-radius: 8px;
  overflow: hidden;
  background: var(--card);
}
.meta-grid div { padding: 14px 16px; border-left: 1px solid var(--line); }
.meta-grid div:first-child { border-left: none; }
.meta-grid span {
  display: block;
  font-family: var(--mono);
  font-size: 10.5px;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--ink-faint);
  margin-bottom: 4px;
}
.meta-grid strong { font-size: 15px; font-weight: 600; }

.hero-image {
  margin: 0;
  border: 1px solid var(--manila-line);
  border-radius: 10px;
  padding: 10px;
  background: var(--card);
  position: relative;
  transform: rotate(0.6deg);
}
.hero-image::after {
  content: 'CASE FILE · 2026';
  position: absolute;
  top: -14px;
  right: 18px;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  background: var(--brick);
  color: #fff;
  padding: 5px 10px;
  border-radius: 4px;
  transform: rotate(-2deg);
  box-shadow: 0 3px 8px rgba(30,42,38,0.18);
}

/* ---------- image placeholders ---------- */
.placeholder {
  --ratio: 4/3;
  aspect-ratio: var(--ratio);
  width: 100%;
  border-radius: 6px;
  background:
    repeating-linear-gradient(135deg, var(--paper-deep) 0 10px, var(--card) 10px 20px);
  border: 1px dashed var(--ink-faint);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 10px;
  color: var(--ink-faint);
  text-align: center;
  padding: 20px;
}
.placeholder svg { width: 30px; height: 30px; opacity: 0.6; }
.placeholder span {
  font-family: var(--mono);
  font-size: 11.5px;
  letter-spacing: 0.03em;
  max-width: 26ch;
  line-height: 1.4;
}

.bordered {
  border: 1px solid var(--line);
  border-radius: 10px;
  background: var(--card);
  padding: 8px;
}
figure { margin: 0; }
figcaption {
  font-size: 13px;
  color: var(--ink-soft);
  padding: 10px 8px 4px;
}
.large-visual .placeholder { --ratio: 16/9; }

/* ---------- problem section ---------- */
.problem-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
  margin-bottom: 36px;
}
.problem-grid article {
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 20px;
  background: var(--card);
}
.problem-grid h3 { font-size: 16px; font-weight: 600; margin-bottom: 8px; }
.problem-grid p { color: var(--ink-soft); font-size: 14.5px; margin: 0; }

.problem-statement {
  border-left: 3px solid var(--brick);
  background: var(--brick-soft);
  padding: 20px 24px;
  border-radius: 0 8px 8px 0;
}
.problem-statement span {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--brick);
}
.problem-statement p {
  font-family: var(--display);
  font-size: 19px;
  margin-top: 8px;
  max-width: 58ch;
}

/* ---------- research ---------- */
.research-table-wrap { overflow-x: auto; margin-bottom: 32px; }
.research-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 14.5px;
  min-width: 620px;
}
.research-table th {
  text-align: left;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--ink-faint);
  padding: 10px 14px;
  border-bottom: 2px solid var(--ink);
}
.research-table td {
  padding: 14px 14px;
  border-bottom: 1px solid var(--line);
  vertical-align: top;
  color: var(--ink-soft);
}
.research-table td strong { color: var(--ink); }

.research-questions {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 14px;
}
.research-questions div {
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 16px;
  background: var(--card);
}
.research-questions span {
  font-family: var(--mono);
  font-size: 11px;
  color: var(--brick);
}
.research-questions p { margin: 8px 0 0; font-size: 14.5px; font-weight: 500; }

/* ---------- journey insight ---------- */
.journey-insight {
  margin-top: 24px;
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 20px 24px;
  background: var(--paper-deep);
}
.journey-insight-label {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--teal);
  margin-bottom: 8px;
}
.journey-insight p { margin: 0; color: var(--ink-soft); max-width: 68ch; }

/* ---------- personas ---------- */
.persona-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
}
.persona { border: 1px solid var(--line); border-radius: 10px; overflow: hidden; background: var(--card); }
.persona .placeholder { --ratio: 4/3; border-radius: 0; border: none; border-bottom: 1px solid var(--line); }
.persona-note { padding: 16px 18px; }
.persona-note span {
  font-family: var(--mono);
  font-size: 11px;
  color: var(--brick);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}
.persona-note p { margin: 6px 0 0; font-size: 14.5px; color: var(--ink-soft); }

/* ---------- insight block ---------- */
.insight-block {
  border: 1px solid var(--manila-line);
  background: var(--manila);
  border-radius: 10px;
  padding: 36px 40px;
}
.insight-lead {
  font-family: var(--display);
  font-style: italic;
  font-size: clamp(1.3rem, 2.6vw, 1.8rem);
  line-height: 1.35;
  max-width: 34ch;
  margin: 0;
  color: var(--teal-deep);
}
.insight-block > p:last-child {
  margin-top: 18px;
  color: var(--ink-soft);
  max-width: 62ch;
}

/* ---------- before / after ---------- */
.before-after {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: 20px;
  margin-bottom: 32px;
}
.ba-panel {
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 22px 24px;
  background: var(--card);
}
.ba-panel.revised { border-color: var(--teal); background: #EEF4F1; }
.ba-panel span {
  font-family: var(--mono);
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--ink-faint);
}
.ba-panel h3 { font-size: 19px; margin-top: 6px; }
.ba-panel p { color: var(--ink-soft); font-size: 14px; margin: 10px 0 14px; }
.ba-panel strong { font-family: var(--mono); font-size: 22px; color: var(--ink); }
.ba-panel small { display: block; color: var(--ink-faint); font-size: 12px; margin-top: 2px; }
.ba-arrow { font-size: 24px; color: var(--brick); }

.decision-copy { max-width: 62ch; }
.decision-copy h3 { font-size: 17px; margin-bottom: 8px; }
.decision-copy p { color: var(--ink-soft); }

/* ---------- wireframes ---------- */
.wireframe-block {
  display: grid;
  grid-template-columns: 0.9fr 1.4fr;
  gap: 26px;
  align-items: center;
  margin-bottom: 26px;
}
.wireframe-copy span {
  font-family: var(--mono);
  font-size: 11px;
  color: var(--brick);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}
.wireframe-copy h3 { font-size: 17px; margin-top: 6px; }
.wireframe-copy p { color: var(--ink-soft); font-size: 14.5px; margin-top: 8px; }
.wireframe-row { display: grid; grid-template-columns: repeat(4, 1fr); gap: 8px; }
.wireframe-row .placeholder { --ratio: 3/4; }

.flow-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 18px;
}
.flow-grid .placeholder { --ratio: 16/9; }

/* ---------- video ---------- */
.video-wrap { max-width: 720px; margin: 0 auto; }
.video-wrap video { width: 100%; border-radius: 6px; display: block; }
.video-wrap .placeholder { --ratio: 16/9; margin: 0; }

/* ---------- final dashboard / ui rationale ---------- */
.final-dashboard { margin-bottom: 36px; }
.final-dashboard .placeholder { --ratio: 16/9.2; }

.ui-rationale {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
  margin-bottom: 36px;
}
.ui-rationale article {
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 20px;
  background: var(--card);
}
.ui-rationale span {
  font-family: var(--mono);
  font-size: 10.5px;
  color: var(--teal);
  letter-spacing: 0.06em;
}
.ui-rationale h3 { font-size: 15.5px; margin: 8px 0 8px; line-height: 1.35; }
.ui-rationale p { color: var(--ink-soft); font-size: 14px; margin: 0; }

.screen-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
}
.screen-grid .placeholder { --ratio: 4/3; }

/* ---------- testing ---------- */
.testing-stat {
  display: flex;
  align-items: baseline;
  gap: 16px;
  padding: 22px 26px;
  margin-bottom: 30px;
  background: #EEF4F1;
  border-color: var(--teal);
}
.testing-stat strong {
  font-family: var(--mono);
  font-size: 40px;
  color: var(--teal-deep);
}
.testing-stat span { color: var(--ink-soft); font-size: 14.5px; }

.testing-findings {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
}
.testing-findings article {
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 20px;
  background: var(--card);
}
.testing-findings span {
  font-family: var(--mono);
  font-size: 10.5px;
  color: var(--ink-faint);
  text-transform: uppercase;
}
.testing-findings h3 { font-size: 16px; margin: 6px 0 8px; }
.testing-findings p { color: var(--ink-soft); font-size: 14px; margin: 0 0 12px; }
.testing-findings strong {
  display: block;
  font-size: 13.5px;
  color: var(--brick);
  font-weight: 600;
  border-top: 1px solid var(--line);
  padding-top: 10px;
}

/* ---------- outcome ---------- */
.outcome-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
  margin-bottom: 36px;
}
.outcome-grid div {
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 22px;
  text-align: center;
  background: var(--card);
}
.outcome-grid strong {
  display: block;
  font-family: var(--mono);
  font-size: 26px;
  color: var(--teal-deep);
}
.outcome-grid span { font-size: 13px; color: var(--ink-soft); }

.measurement {
  border: 1px solid var(--manila-line);
  background: var(--manila);
  border-radius: 10px;
  padding: 26px 28px;
}
.measurement h3 { font-size: 16px; margin-bottom: 16px; }
.measurement-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
}
.measurement-grid p { margin: 0; font-size: 13.5px; color: var(--ink-soft); }
.measurement-grid strong { color: var(--ink); font-size: 14px; }
.measurement small { display: block; margin-top: 18px; color: var(--ink-faint); font-size: 12px; }

/* ---------- reflection ---------- */
.next-steps {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
  margin-bottom: 32px;
}
.next-steps > div {
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 20px;
  background: var(--card);
}
.next-steps span {
  font-family: var(--mono);
  font-size: 11px;
  color: var(--brick);
}
.next-steps h3 { font-size: 15.5px; margin: 8px 0; }
.next-steps p { color: var(--ink-soft); font-size: 14px; margin: 0; }

.project-note {
  border-left: 3px solid var(--ink-faint);
  padding: 16px 22px;
  background: var(--paper-deep);
  border-radius: 0 8px 8px 0;
}
.project-note strong { font-family: var(--mono); font-size: 11px; text-transform: uppercase; letter-spacing: 0.06em; color: var(--ink-faint); }
.project-note p { margin: 8px 0 0; color: var(--ink-soft); font-size: 13.5px; max-width: 70ch; }

/* ---------- snapshot strip (scan-first content) ---------- */
.snapshot {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1px;
  background: var(--ink);
  border-radius: 10px;
  overflow: hidden;
  margin: 0 0 8px;
}
.snapshot div {
  background: var(--teal-deep);
  color: var(--card);
  padding: 20px 22px;
}
.snapshot strong {
  display: block;
  font-family: var(--mono);
  font-size: 24px;
}
.snapshot span { font-size: 12.5px; opacity: 0.85; }

/* ---------- footer ---------- */
.footer {
  text-align: center;
  padding: 40px 0 60px;
  color: var(--ink-faint);
  font-size: 13px;
  font-family: var(--mono);
}

.next-case-study {
  margin-top: 80px;
  padding: 80px 0;
  border-top: 1px solid var(--border-color);
}

.next-case-content {
  max-width: 760px;
}

.next-case-content h2 {
  margin: 12px 0 16px;
}

.next-case-content p {
  max-width: 600px;
  margin-bottom: 32px;
}

.next-case-link {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  font-weight: 600;
}

.next-case-link span {
  font-size: 20px;
  transition: transform 0.2s ease;
}

.next-case-link:hover span {
  transform: translateX(5px);
}
/* ============================================================
   RESPONSIVE
   ============================================================ */
@media (max-width: 980px) {
  main { padding: 0 22px; }
  .header-inner { padding: 12px 22px; }
  .hero { grid-template-columns: 1fr; gap: 32px; padding-top: 36px; }
  .hero-image { order: -1; transform: none; }
  .meta-grid { grid-template-columns: repeat(2, 1fr); }
  .meta-grid div:nth-child(3) { border-left: none; }
  .problem-grid,
  .ui-rationale,
  .testing-findings,
  .outcome-grid,
  .screen-grid { grid-template-columns: 1fr 1fr; }
  .research-questions { grid-template-columns: 1fr 1fr; }
  .persona-grid,
  .next-steps,
  .flow-grid { grid-template-columns: 1fr; }
  .wireframe-block { grid-template-columns: 1fr; }
  .wireframe-row { grid-template-columns: repeat(4, 1fr); }
  .before-after { grid-template-columns: 1fr; }
  .ba-arrow { transform: rotate(90deg); justify-self: center; }
  .measurement-grid { grid-template-columns: 1fr 1fr; }
  .snapshot { grid-template-columns: 1fr; }
}

@media (max-width: 600px) {
  body { font-size: 16px; }
  .section { padding: 56px 0; }
  .problem-grid,
  .ui-rationale,
  .testing-findings,
  .outcome-grid,
  .screen-grid,
  .research-questions,
  .wireframe-row,
  .measurement-grid { grid-template-columns: 1fr; }
  .meta-grid { grid-template-columns: 1fr 1fr; }
  .meta-grid div:nth-child(odd) { border-left: none; }
  .meta-grid div:nth-child(n+3) { border-top: 1px solid var(--line); }
  .section-heading { padding: 22px 20px 4px; }
}