:root {
  --border: rgba(0,0,0,.12);
  --border-light: rgba(0,0,0,.08);
  --shadow-sm: 0 4px 12px rgba(0,0,0,.05);
  --shadow-xs: 0 2px 6px rgba(0,0,0,.04);
  --shadow: 0 10px 38px rgba(0,0,0,.08);
  --radius-lg: 16px;
  --red-dark: #c41e14;
  --white: #fff;
}
.dark {
  --border: rgba(255,255,255,.12);
  --border-light: rgba(255,255,255,.08);
  --shadow-sm: 0 4px 12px rgba(0,0,0,.25);
  --shadow-xs: 0 2px 6px rgba(0,0,0,.15);
  --shadow: 0 10px 40px rgba(0,0,0,.35);
}

/* HERO */
.partners-hero {
  padding: 64px 0 32px;
  text-align: center;
  position: relative;
  overflow: hidden;
  background: var(--bg);
  background: radial-gradient(circle at center top, var(--card) 0%, var(--bg) 60%);
}
.partners-hero .kicker {
  font-weight: 800;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--muted);
  font-size: .9rem;
  margin: 0 0 12px;
}
.partners-hero .display {
  font-family: var(--font-display);
  font-size: clamp(2.8rem, 7vw, 5rem);
  line-height: .9;
  margin: 0 auto 16px;
  letter-spacing: -0.02em;
  max-width: 14ch;
}
.partners-hero .sublead {
  color: var(--ink-weak);
  max-width: 80ch;
  margin: 0 auto 32px;
  font-size: 1.1rem;
}

/* LAYOUT */
.partners-frame {
  display: grid;
  gap: var(--gap);
  margin-top: 40px;
  grid-template-columns: minmax(0, 1fr);
}
@media (min-width: 1024px) {
  .partners-frame {
    grid-template-columns: 280px minmax(0, 1fr);
  }
}

/* STICKY TIER NAVIGATION RAIL */
.tier-rail {
  position: sticky;
  top: 92px;
  display: none;
  padding: 16px;
  border-radius: var(--radius);
  background: var(--card);
  border: 1px solid var(--border-light);
  box-shadow: var(--shadow-sm);
  align-self: start;
  height: fit-content;
  transition: all 0.2s ease-out;
}
@media (min-width: 1024px) {
  .tier-rail {
    display: grid;
    gap: 10px;
  }
}

.tier-link {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 14px;
  border-radius: 8px;
  background: var(--bg);
  color: var(--ink);
  text-decoration: none;
  font-weight: 700;
  border: 1px solid var(--border);
  transition: all 0.2s ease-out;
  font-size: 0.95rem;
}
.tier-link:hover {
  background: var(--border-light);
  transform: translateX(4px);
  box-shadow: var(--shadow-xs);
}
.tier-link.active {
  background: var(--red);
  color: var(--white);
  border-color: var(--red);
  outline: none;
  box-shadow: var(--shadow);
  transform: none;
}
.tier-link.active:hover {
  background: var(--red-dark);
  border-color: var(--red-dark);
}

.rail-note {
  margin-top: 10px;
  font-size: .8rem;
  color: var(--muted);
  border-top: 1px dashed var(--border-light);
  padding-top: 10px;
  line-height: 1.4;
}

/* TIERS */
.tiers {
  display: grid;
  gap: 80px;
}
.tier {
  scroll-margin-top: 100px;
  padding-top: 20px;
}
@media (min-width: 1024px) {
  .tier {
    scroll-margin-top: 80px;
  }
}

.tier-head {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 6px;
  margin-bottom: 24px;
  border-bottom: 2px solid var(--border-light);
  padding-bottom: 12px;
  position: relative;
}
.tier-head .kicker {
  margin-bottom: 0;
  font-size: 0.9rem;
  color: var(--red);
  font-weight: 700;
}
.tier-title {
  margin: 0;
  font-family: var(--font-display);
  font-size: clamp(2rem, 4.5vw, 3rem);
  letter-spacing: -0.01em;
  line-height: 1.1;
  color: var(--ink);
}
.tier-description {
  font-size: 1rem;
  color: var(--ink-weak);
  margin-top: 8px;
  max-width: 60ch;
}

/* LOGO GRID */
.logo-grid {
  --min: 160px;
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(var(--min), 1fr));
  gap: var(--gap);
  margin-top: 32px;
}
.logo-grid.md { --min: 140px; }
.logo-grid.lg { --min: 180px; }
.logo-grid.xl { --min: 220px; }

.logo-card {
  display: grid;
  place-items: center;
  min-height: 140px;
  padding: 16px;
  border-radius: var(--radius-lg);
  background: var(--bg);
  border: 1px solid var(--border);
  text-decoration: none;
  transition: transform .2s ease, box-shadow .2s ease, border-color .2s ease;
  box-shadow: var(--shadow-sm);
}
.logo-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow);
  border-color: var(--red);
}
.logo-card img {
  max-width: 90%;
  max-height: 72px;
  object-fit: contain;
  width: auto;
  filter: grayscale(80%);
  opacity: .8;
  transition: filter .2s ease, opacity .2s ease;
}
.logo-card:hover img {
  filter: none;
  opacity: 1;
}

/* CTA */
.partners-cta {
  margin: 40px 0 0;
  padding: 30px 0;
}
.cta {
  text-align: center;
  padding: 48px 32px;
  border-radius: var(--radius-lg);
  background: var(--card);
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
}
.cta h3 {
  margin: 0 0 12px;
  font-family: var(--font-display);
  font-size: clamp(1.8rem, 4vw, 2.8rem);
  letter-spacing: -0.01em;
}
.cta p {
  margin: 0 auto 24px;
  color: var(--ink-weak);
  max-width: 60ch;
  font-size: 1.1rem;
}
.btn.red {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 14px 24px;
  border: 2px solid var(--red);
  background: var(--red);
  color: var(--white);
  border-radius: 12px;
  font-weight: 900;
  letter-spacing: .03em;
  text-transform: uppercase;
  transition: transform .16s ease, box-shadow .16s ease, background .16s ease;
}
.btn.red:hover {
  transform: translateY(-3px);
  background: var(--red-dark);
  box-shadow: var(--shadow);
}

section {
  padding: 20px 0;
}