/* ── Viestri · Case Study Deep-Dive Shared Styles ─────────── */
:root {
  --black:       #0A0A0F;
  --black-mid:   #1A1A2E;
  --blue:        #2563EB;
  --blue-dark:   #1D4ED8;
  --blue-light:  #3B82F6;
  --blue-pale:   #EFF6FF;
  --blue-pale2:  #DBEAFE;
  --white:       #FFFFFF;
  --gray-50:     #F9FAFB;
  --gray-100:    #F3F4F6;
  --gray-200:    #E5E7EB;
  --gray-400:    #9CA3AF;
  --gray-600:    #4B5563;
  --shadow-sm:   0 1px 3px rgba(0,0,0,0.08), 0 1px 2px rgba(0,0,0,0.06);
  --shadow-md:   0 4px 16px rgba(0,0,0,0.08), 0 2px 6px rgba(0,0,0,0.05);
  --shadow-lg:   0 10px 40px rgba(0,0,0,0.10), 0 4px 12px rgba(0,0,0,0.06);
  --radius:      12px;
  --radius-lg:   20px;
  --radius-xl:   28px;
}

* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  font-family: 'Inter', -apple-system, system-ui, sans-serif;
  background: var(--white);
  color: var(--black);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}
a { color: var(--blue); text-decoration: none; }
a:hover { color: var(--blue-dark); }

.container { max-width: 960px; margin: 0 auto; padding: 0 32px; }

/* ── Top nav (mini) ── */
.cs-nav {
  position: sticky; top: 0; z-index: 50;
  background: rgba(255,255,255,0.92);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--gray-200);
}
.cs-nav-inner {
  max-width: 1160px; margin: 0 auto; padding: 16px 32px;
  display: flex; align-items: center; justify-content: space-between;
}
.cs-nav-brand {
  display: flex; align-items: center; gap: 10px;
  font-weight: 800; font-size: 18px; color: var(--black); letter-spacing: -0.02em;
}
.cs-nav-brand img { height: 28px; width: auto; }
.cs-nav-links { display: flex; align-items: center; gap: 28px; }
.cs-nav-links a { font-size: 14px; font-weight: 600; color: var(--gray-600); }
.cs-nav-links a:hover { color: var(--black); }
.cs-nav-cta {
  background: var(--blue); color: var(--white);
  padding: 9px 18px; border-radius: var(--radius);
  font-size: 13px; font-weight: 700; letter-spacing: 0.01em;
  transition: background .2s;
}
.cs-nav-cta:hover { background: var(--blue-dark); color: var(--white); }
@media (max-width: 720px) {
  .cs-nav-links a:not(.cs-nav-cta) { display: none; }
}

/* ── Hero ── */
.cs-hero { padding: 72px 0 48px; background: var(--white); }
.cs-back {
  display: inline-flex; align-items: center; gap: 6px;
  font-size: 13px; font-weight: 600; color: var(--gray-600);
  margin-bottom: 28px;
}
.cs-back:hover { color: var(--blue); }
.cs-badges { display: flex; align-items: center; gap: 10px; flex-wrap: wrap; margin-bottom: 22px; }
.cs-id {
  display: inline-block; background: var(--black); color: var(--white);
  font-size: 11px; font-weight: 800; letter-spacing: .14em; text-transform: uppercase;
  padding: 6px 12px; border-radius: 6px;
}
.cs-vertical {
  display: inline-block; background: var(--blue-pale); color: var(--blue-dark);
  font-size: 12px; font-weight: 700; letter-spacing: .04em;
  padding: 6px 12px; border-radius: 6px; border: 1px solid var(--blue-pale2);
}
.cs-h1 {
  font-size: clamp(32px, 5vw, 52px); font-weight: 900;
  letter-spacing: -0.03em; line-height: 1.1; color: var(--black);
  margin-bottom: 20px; max-width: 820px;
}
.cs-lead {
  font-size: 18px; line-height: 1.65; color: var(--gray-600);
  max-width: 760px;
}

/* ── Stat grid ── */
.cs-stat-grid {
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px;
  margin: 48px 0 56px;
}
.cs-stat {
  background: var(--gray-50);
  border: 1px solid var(--gray-200);
  border-radius: var(--radius-lg);
  padding: 24px 22px;
}
.cs-stat.hero {
  background: var(--blue-pale);
  border-color: var(--blue-pale2);
  border-width: 1.5px;
}
.cs-stat-value {
  font-size: clamp(28px, 3.4vw, 38px); font-weight: 900;
  letter-spacing: -0.04em; line-height: 1; color: var(--blue);
}
.cs-stat.hero .cs-stat-value { color: var(--blue-dark); }
.cs-stat-label {
  font-size: 11px; font-weight: 700; color: var(--gray-400);
  letter-spacing: .08em; text-transform: uppercase;
  margin-top: 10px;
}
@media (max-width: 800px) {
  .cs-stat-grid { grid-template-columns: repeat(2, 1fr); }
}

/* ── Section blocks ── */
.cs-section { margin-bottom: 40px; }
.cs-section-title {
  font-size: 12px; font-weight: 800; color: var(--blue);
  letter-spacing: .14em; text-transform: uppercase;
  margin-bottom: 14px;
}
.cs-section h2 {
  font-size: 28px; font-weight: 800; color: var(--black);
  letter-spacing: -0.02em; margin-bottom: 16px;
}
.cs-section p {
  font-size: 16px; line-height: 1.75; color: var(--gray-600);
  margin-bottom: 16px;
}
.cs-section ul {
  list-style: none; padding: 0; margin: 14px 0;
}
.cs-section li {
  position: relative; padding: 10px 0 10px 26px;
  font-size: 15px; line-height: 1.7; color: var(--gray-600);
  border-bottom: 1px solid var(--gray-100);
}
.cs-section li:last-child { border-bottom: none; }
.cs-section li::before {
  content: ''; position: absolute; left: 4px; top: 18px;
  width: 8px; height: 8px; border-radius: 50%;
  background: var(--blue);
}
.cs-section li strong { color: var(--black); font-weight: 700; }

/* ── Callout ── */
.cs-callout {
  background: var(--gray-50);
  border-left: 4px solid var(--blue);
  border-radius: 0 var(--radius) var(--radius) 0;
  padding: 22px 26px;
  margin: 32px 0;
  font-size: 16px; line-height: 1.7; color: var(--gray-600);
}
.cs-callout strong { color: var(--black); font-weight: 800; }

/* ── Table ── */
.cs-table {
  width: 100%; border-collapse: collapse;
  margin: 16px 0 24px;
  border: 1px solid var(--gray-200);
  border-radius: var(--radius); overflow: hidden;
}
.cs-table th, .cs-table td {
  text-align: left; padding: 14px 18px;
  font-size: 14px; line-height: 1.55;
  border-bottom: 1px solid var(--gray-200);
}
.cs-table tr:last-child td { border-bottom: none; }
.cs-table th {
  background: var(--gray-50); color: var(--black);
  font-weight: 700; font-size: 11px;
  text-transform: uppercase; letter-spacing: .08em;
}
.cs-table td { color: var(--gray-600); }
.cs-table td.right { text-align: right; font-variant-numeric: tabular-nums; font-weight: 600; color: var(--black); }
@media (max-width: 640px) {
  .cs-table th, .cs-table td { padding: 10px 12px; font-size: 13px; }
}

/* ── Anonymity / source note ── */
.cs-note {
  font-size: 13px; font-style: italic;
  color: var(--gray-400);
  background: var(--gray-50);
  border-left: 2px solid var(--gray-200);
  padding: 12px 18px;
  border-radius: 0 6px 6px 0;
  margin-top: 32px;
}

/* ── CTA strip ── */
.cs-cta {
  margin: 72px 0 80px;
  background: var(--black);
  color: var(--white);
  border-radius: var(--radius-xl);
  padding: 56px 48px;
  text-align: center;
}
.cs-cta h3 {
  font-size: clamp(24px, 3.4vw, 36px); font-weight: 900;
  letter-spacing: -0.02em; margin-bottom: 14px;
}
.cs-cta p {
  font-size: 16px; line-height: 1.7;
  color: rgba(255,255,255,0.65);
  max-width: 580px; margin: 0 auto 28px;
}
.cs-cta a {
  display: inline-block;
  background: var(--blue); color: var(--white);
  padding: 16px 34px; border-radius: var(--radius);
  font-size: 15px; font-weight: 700; letter-spacing: 0.01em;
  transition: background .2s, transform .2s;
}
.cs-cta a:hover { background: var(--blue-dark); color: var(--white); transform: translateY(-2px); }

/* ── Other cases (related) ── */
.cs-related { padding: 48px 0 80px; background: var(--gray-50); border-top: 1px solid var(--gray-200); }
.cs-related-title {
  font-size: 12px; font-weight: 800; color: var(--blue);
  letter-spacing: .14em; text-transform: uppercase;
  margin-bottom: 24px; text-align: center;
}
.cs-related-grid {
  display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px;
}
.cs-related-card {
  background: var(--white); border: 1px solid var(--gray-200);
  border-radius: var(--radius-lg); padding: 22px;
  transition: transform .25s, box-shadow .25s, border-color .25s;
  display: flex; flex-direction: column; gap: 10px;
}
.cs-related-card:hover {
  transform: translateY(-3px); box-shadow: var(--shadow-md);
  border-color: var(--blue-pale2);
}
.cs-related-card .cs-id { font-size: 9.5px; padding: 4px 8px; }
.cs-related-card h4 { font-size: 16px; font-weight: 800; color: var(--black); letter-spacing: -0.01em; line-height: 1.3; }
.cs-related-card p { font-size: 13px; color: var(--gray-600); line-height: 1.55; }
@media (max-width: 760px) {
  .cs-related-grid { grid-template-columns: 1fr; }
}

/* ── Footer ── */
.cs-footer {
  background: var(--black); color: rgba(255,255,255,0.55);
  padding: 36px 0; font-size: 13px;
  text-align: center;
}
.cs-footer a { color: rgba(255,255,255,0.75); }
.cs-footer a:hover { color: var(--white); }