/* ==========================================================================
   CranioPlan — style.css
   Single-page static site for a remote orthognathic surgery planning service.
   ========================================================================== */

/* --------------------------------------------------------------------------
   1. CSS Custom Properties (Design Tokens)
   -------------------------------------------------------------------------- */
:root {
  --navy:       #0D1B3E;
  --bone:       #F1EFE9;
  --gray-mid:   #8A8F99;
  --gray-light: #E3E0D9;
  --accent:     #6B8FA0;
  --white:      #FFFFFF;

  /* Typography */
  --font-display:  'Cormorant Garamond', Georgia, serif;
  --font-body:     'DM Sans', system-ui, sans-serif;
  --font-mono:     'IBM Plex Mono', 'Courier New', monospace;

  /* Type Scale */
  --size-hero:    clamp(2.8rem, 5vw, 5rem);
  --size-h2:      clamp(1.8rem, 3vw, 2.8rem);
  --size-h3:      1.3rem;
  --size-body:    1rem;
  --size-label:   0.78rem;

  /* Spacing */
  --section-pad:  clamp(80px, 10vw, 140px);
  --max-width:    1200px;
  --gutter:       clamp(20px, 4vw, 48px);
}


/* --------------------------------------------------------------------------
   2. Reset & Base
   -------------------------------------------------------------------------- */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  background-color: var(--bone);
  color: var(--navy);
  font-family: var(--font-body);
  font-weight: 300;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

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

a {
  color: inherit;
  text-decoration: none;
}

ul {
  list-style: none;
}

button {
  cursor: pointer;
  font-family: inherit;
  border: none;
  background: none;
}


/* --------------------------------------------------------------------------
   3. Layout Utilities
   -------------------------------------------------------------------------- */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin-left: auto;
  margin-right: auto;
  padding-left: var(--gutter);
  padding-right: var(--gutter);
}

/* Section label (monospace, uppercase, letter-spaced) */
.section-label {
  font-family: var(--font-mono);
  font-size: var(--size-label);
  font-weight: 400;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--accent);
  display: block;
  margin-bottom: 16px;
}

/* Section headline */
.section-headline {
  font-family: var(--font-display);
  font-size: var(--size-h2);
  font-weight: 500;
  color: var(--navy);
  line-height: 1.2;
  margin-bottom: 1rem;
}

/* Horizontal divider */
.section-divider {
  width: 100%;
  height: 1px;
  background-color: var(--gray-light);
  border: none;
}


/* --------------------------------------------------------------------------
   4. Buttons
   -------------------------------------------------------------------------- */

/* Primary button — navy fill, no border-radius */
.btn-primary {
  display: inline-block;
  background-color: var(--navy);
  color: var(--bone);
  font-family: var(--font-body);
  font-size: 0.9rem;
  font-weight: 400;
  letter-spacing: 0.04em;
  padding: 14px 32px;
  border-radius: 0;
  border: 1px solid var(--navy);
  transition: background-color 0.2s ease, color 0.2s ease;
}

.btn-primary:hover {
  background-color: var(--accent);
  border-color: var(--accent);
  color: var(--white);
}

/* Secondary button — outlined, transparent */
.btn-secondary {
  display: inline-block;
  background-color: transparent;
  color: var(--navy);
  font-family: var(--font-body);
  font-size: 0.9rem;
  font-weight: 400;
  letter-spacing: 0.04em;
  padding: 14px 32px;
  border-radius: 0;
  border: 1px solid var(--navy);
  transition: background-color 0.2s ease, color 0.2s ease;
}

.btn-secondary:hover {
  background-color: var(--navy);
  color: var(--bone);
}

/* Ghost button for dark sections — bone outline */
.btn-ghost {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  background-color: transparent;
  color: var(--bone);
  font-family: var(--font-body);
  font-size: 0.9rem;
  font-weight: 400;
  letter-spacing: 0.04em;
  padding: 14px 32px;
  border-radius: 0;
  border: 1px solid rgba(245, 240, 232, 0.4);
  transition: background-color 0.2s ease, border-color 0.2s ease;
}

.btn-ghost:hover {
  background-color: rgba(245, 240, 232, 0.08);
  border-color: var(--bone);
}

/* WhatsApp ghost button — special hover */
.btn-ghost--whatsapp:hover {
  background-color: #25D366;
  border-color: #25D366;
}

/* Nav CTA — compact, no border-radius */
.btn-nav {
  display: inline-block;
  background-color: var(--navy);
  color: var(--bone);
  font-family: var(--font-body);
  font-size: 0.82rem;
  font-weight: 400;
  letter-spacing: 0.05em;
  padding: 10px 22px;
  border-radius: 0;
  border: 1px solid var(--navy);
  transition: background-color 0.2s ease, color 0.2s ease;
  white-space: nowrap;
}

.btn-nav:hover {
  background-color: var(--accent);
  border-color: var(--accent);
  color: var(--white);
}


/* --------------------------------------------------------------------------
   5. Navigation
   -------------------------------------------------------------------------- */
.site-nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  background-color: var(--white);
  border-bottom: 1px solid transparent;
  transition: border-color 0.3s ease, box-shadow 0.3s ease;
}

/* Scrolled state — added via JS */
.site-nav.scrolled {
  border-bottom-color: var(--gray-light);
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 108px;
  gap: 32px;
}

/* Logo */
.nav-logo {
  flex-shrink: 0;
  display: flex;
  align-items: center;
}

.nav-logo img {
  max-height: 96px;
  width: auto;
}

/* Desktop nav links */
.nav-links {
  display: flex;
  align-items: center;
  gap: 22px;   /* reduced from 32px to accommodate 6 links */
  flex: 1;
  justify-content: flex-end;
  margin-right: 24px;
}

.nav-links a {
  font-family: var(--font-body);
  font-size: 0.88rem;
  font-weight: 400;
  color: var(--navy);
  letter-spacing: 0.02em;
  opacity: 0.8;
  transition: opacity 0.2s ease, color 0.2s ease;
  white-space: nowrap;
}

.nav-links a:hover {
  opacity: 1;
  color: var(--accent);
}

/* Active page indicator — set via aria-current="page" on sub-pages */
.nav-links a[aria-current="page"] {
  color: var(--accent);
  opacity: 1;
}

.nav-overlay a[aria-current="page"] {
  color: var(--accent);
}

/* Hamburger (mobile only) */
.nav-hamburger {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 32px;
  height: 32px;
  padding: 4px;
  background: none;
  border: none;
  cursor: pointer;
  flex-shrink: 0;
}

.nav-hamburger span {
  display: block;
  width: 100%;
  height: 1px;
  background-color: var(--navy);
  transition: transform 0.3s ease, opacity 0.3s ease;
}

/* Hamburger open state */
.nav-hamburger.open span:nth-child(1) {
  transform: translateY(6px) rotate(45deg);
}

.nav-hamburger.open span:nth-child(2) {
  opacity: 0;
}

.nav-hamburger.open span:nth-child(3) {
  transform: translateY(-6px) rotate(-45deg);
}

/* Mobile overlay menu */
.nav-overlay {
  display: none;
  position: fixed;
  inset: 0;
  background-color: var(--white);
  z-index: 99;
  flex-direction: column;
  align-items: flex-start;
  justify-content: center;
  padding: 80px var(--gutter) var(--gutter);
  gap: 0;
}

.nav-overlay.open {
  display: flex;
}

.nav-overlay a {
  font-family: var(--font-display);
  font-size: clamp(1.6rem, 4vw, 2.2rem);
  font-weight: 400;
  color: var(--navy);
  padding: 14px 0;
  border-bottom: 1px solid var(--gray-light);
  width: 100%;
  transition: color 0.2s ease;
}

.nav-overlay a:hover {
  color: var(--accent);
}

.nav-overlay .btn-nav {
  margin-top: 32px;
  font-size: 1rem;
  padding: 16px 40px;
}


/* --------------------------------------------------------------------------
   6. Hero
   -------------------------------------------------------------------------- */
.hero {
  min-height: 90vh;
  display: flex;
  align-items: center;
  padding-top: 108px; /* offset fixed nav */
  padding-bottom: clamp(60px, 8vw, 100px);
  border-bottom: 1px solid var(--gray-light);
}

.hero-content {
  max-width: 640px;
  flex: 1 1 auto;
  min-width: 0;
}

/* Eyebrow label above headline */
.hero-eyebrow {
  font-family: var(--font-mono);
  font-size: var(--size-label);
  font-weight: 400;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--gray-mid);
  display: block;
  margin-bottom: 24px;
}

.hero-headline {
  font-family: var(--font-display);
  font-size: var(--size-hero);
  font-weight: 300;
  color: var(--navy);
  line-height: 1.08;
  margin-bottom: 28px;
}

/* Accent word styling — applied inline */
.hero-headline em {
  font-style: normal;
  font-weight: 400;
  color: var(--accent);
}

.hero-subheadline {
  font-family: var(--font-body);
  font-size: 1.05rem;
  font-weight: 300;
  color: var(--gray-mid);
  line-height: 1.7;
  margin-bottom: 40px;
  max-width: 560px;
}

.hero-actions {
  display: flex;
  align-items: center;
  gap: 16px;
  flex-wrap: wrap;
}

/* Two-column hero layout — text left, logo right */
.hero-layout {
  display: flex;
  align-items: center;
  gap: clamp(40px, 6vw, 80px);
}

/* Hero logo mark — right side, decorative — constrained to 46% max */
.hero-logo-mark {
  flex: 0 0 auto;
  max-width: 46%;
  overflow: hidden;
  display: flex;
  align-items: center;
  justify-content: center;
}

.hero-logo-img {
  width: 100%;
  max-width: 580px;
  height: auto;
  opacity: 0.72;
}

/* Subtle fade-in on load */
.hero-content {
  opacity: 0;
  transform: translateY(16px);
  animation: heroFadeIn 0.8s ease 0.15s forwards;
}

@keyframes heroFadeIn {
  to {
    opacity: 1;
    transform: translateY(0);
  }
}


/* --------------------------------------------------------------------------
   7. Services
   -------------------------------------------------------------------------- */
.services {
  padding-top: var(--section-pad);
  padding-bottom: var(--section-pad);
  border-bottom: 1px solid var(--gray-light);
}

.services-header {
  margin-bottom: clamp(40px, 6vw, 64px);
}

.services-intro {
  font-size: 1rem;
  font-weight: 300;
  color: var(--gray-mid);
  max-width: 560px;
  margin-top: 12px;
}

/* 3-column grid, collapses to 2 then 1 */
.services-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1px; /* hairline grid — uses background color to show through */
  background-color: var(--gray-light);
  border: 1px solid var(--gray-light);
}

.service-card {
  background-color: var(--white);
  padding: clamp(28px, 3vw, 40px);
  position: relative;
  border-left: 3px solid transparent;
  transition: border-left-color 0.2s ease;
}

.service-card:hover {
  border-left-color: var(--accent);
}

/* Monospace number label */
.service-number {
  font-family: var(--font-mono);
  font-size: var(--size-label);
  font-weight: 500;
  color: var(--accent);
  letter-spacing: 0.1em;
  display: block;
  margin-bottom: 20px;
}

.service-title {
  font-family: var(--font-display);
  font-size: var(--size-h3);
  font-weight: 500;
  color: var(--navy);
  line-height: 1.3;
  margin-bottom: 12px;
}

/* Category prefix in accent colour — e.g. "3D Orthognatic:" */
.service-category {
  color: var(--accent);
  font-weight: 500;
}

.service-description {
  font-size: 0.92rem;
  font-weight: 300;
  color: var(--gray-mid);
  line-height: 1.7;
}


/* --------------------------------------------------------------------------
   8. How It Works
   -------------------------------------------------------------------------- */
.how-it-works {
  padding-top: var(--section-pad);
  padding-bottom: var(--section-pad);
  border-bottom: 1px solid var(--gray-light);
}

.how-it-works-header {
  margin-bottom: clamp(48px, 7vw, 80px);
}

/* 5 steps in a row on desktop */
.steps-track {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 0;
  position: relative;
}

/* Dashed connecting line between steps */
.steps-track::before {
  content: '';
  position: absolute;
  top: 36px; /* aligns with center of step number */
  left: calc(100% / 8);
  right: calc(100% / 8);
  height: 1px;
  border-top: 1px dashed var(--gray-light);
  z-index: 0;
}

.step {
  padding: 0 clamp(16px, 2vw, 28px);
  position: relative;
  z-index: 1;
}

.step:first-child {
  padding-left: 0;
}

.step:last-child {
  padding-right: 0;
}

/* Large monospace step number */
.step-number {
  font-family: var(--font-mono);
  font-size: 2.2rem;
  font-weight: 500;
  color: var(--accent);
  line-height: 1;
  margin-bottom: 24px;
  display: block;
  background-color: var(--bone); /* covers the dashed line */
  width: fit-content;
  padding-right: 12px;
}

.step-title {
  font-family: var(--font-display);
  font-size: 1.2rem;
  font-weight: 500;
  color: var(--navy);
  line-height: 1.3;
  margin-bottom: 10px;
}

.step-description {
  font-size: 0.9rem;
  font-weight: 300;
  color: var(--gray-mid);
  line-height: 1.7;
}


/* --------------------------------------------------------------------------
   9. Software Tools — Logo Grid
   Section 5 in CONTENT.md. Logo-only trust/tool strip, no descriptions.
   4-column on desktop, 2-column on mobile.
   -------------------------------------------------------------------------- */
.software-tools {
  padding-top: var(--section-pad);
  padding-bottom: var(--section-pad);
  border-bottom: 1px solid var(--gray-light);
}

.tools-header {
  margin-bottom: clamp(40px, 6vw, 64px);
}

/* 4-column logo grid
   7 logos → row 1: items 1–4 / row 2: items 5–7 (last cell intentionally empty) */
.tools-logo-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1px;                         /* hairline grid seams */
  background-color: var(--gray-light);
  border: 1px solid var(--gray-light);
}

/* Each logo cell */
.tool-logo-item {
  background-color: var(--white);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: clamp(24px, 3vw, 40px) clamp(20px, 2.5vw, 44px);
  min-height: 128px;
  transition: background-color 0.2s ease;
}

.tool-logo-item:hover {
  background-color: var(--bone);
}

/* Logos that have inherently dark backgrounds (Meshmixer, Lightroom)
   — keep them at full opacity, just constrain the image size */
.tool-logo-item--dark {
  background-color: var(--white);
}

/* Logo image — constrained height, natural width, centred */
.tool-logo-item img {
  display: block;
  max-height: 56px;
  width: auto;
  max-width: 100%;
  height: auto;
  object-fit: contain;
  opacity: 0.85;
  transition: opacity 0.2s ease;
}

.tool-logo-item:hover img {
  opacity: 1;
}


/* --------------------------------------------------------------------------
   10. Contact Section
   -------------------------------------------------------------------------- */
.contact {
  background-color: var(--navy);
  padding-top: var(--section-pad);
  padding-bottom: var(--section-pad);
}

/* Override section label color for dark section */
.contact .section-label {
  color: var(--accent);
}

.contact .section-headline {
  color: var(--bone);
}

.contact-body {
  font-size: 1rem;
  font-weight: 300;
  color: rgba(245, 240, 232, 0.65);
  line-height: 1.7;
  max-width: 520px;
  margin-top: 12px;
  margin-bottom: 40px;
}

.contact-actions {
  display: flex;
  align-items: center;
  gap: 16px;
  flex-wrap: wrap;
}

/* SVG icon sizing inside buttons */
.contact-actions svg,
.btn-ghost svg {
  width: 18px;
  height: 18px;
  flex-shrink: 0;
}


/* --------------------------------------------------------------------------
   11. Footer
   -------------------------------------------------------------------------- */
.site-footer {
  background-color: var(--bone);
  border-top: 1px solid var(--gray-light);
  padding: clamp(32px, 4vw, 52px) 0;
}

.footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  flex-wrap: wrap;
}

.footer-tagline {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 400;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--gray-mid);
}

.footer-meta {
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  gap: 4px;
}

.footer-copyright {
  font-size: 0.82rem;
  font-weight: 300;
  color: var(--gray-mid);
}

.footer-email {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--gray-mid);
  transition: color 0.2s ease;
}

.footer-email:hover {
  color: var(--navy);
}

.footer-legal {
  font-size: 0.78rem;
  font-weight: 300;
  color: var(--gray-mid);
  opacity: 0.7;
  margin-top: 8px;
  width: 100%;
  border-top: 1px solid var(--gray-light);
  padding-top: 16px;
}


/* --------------------------------------------------------------------------
   12. Placeholder Styling (dev only — marks [FILL IN] content)
   -------------------------------------------------------------------------- */
.placeholder {
  background-color: rgba(200, 169, 110, 0.12);
  border: 1px dashed var(--accent);
  color: var(--accent);
  font-family: var(--font-mono);
  font-size: 0.78rem;
  padding: 4px 8px;
  display: inline-block;
}


/* --------------------------------------------------------------------------
   13. Responsive — Tablet (≤ 1024px)
   -------------------------------------------------------------------------- */
@media (max-width: 1024px) {

  .services-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .steps-track {
    grid-template-columns: repeat(3, 1fr);
    gap: clamp(24px, 4vw, 48px);
  }

  /* Hide dashed line on tablet/mobile — too complex to reposition */
  .steps-track::before {
    display: none;
  }

  /* Logo grid: 3 columns on tablet (7 logos → 3+3+1) */
  .tools-logo-grid {
    grid-template-columns: repeat(3, 1fr);
  }

}


/* --------------------------------------------------------------------------
   14. Responsive — Mobile (≤ 768px)
   -------------------------------------------------------------------------- */
@media (max-width: 768px) {

  /* Nav */
  .nav-links,
  .btn-nav {
    display: none;
  }

  .nav-hamburger {
    display: flex;
  }

  /* Hero */
  .hero {
    min-height: 80vh;
    padding-top: 124px;
  }

  .hero-layout {
    flex-direction: column-reverse;
    gap: 32px;
  }

  .hero-logo-mark {
    max-width: 72vw; /* override 46% desktop constraint on mobile */
  }

  .hero-logo-img {
    width: clamp(200px, 60vw, 400px);
    opacity: 0.55;
  }

  .hero-actions {
    flex-direction: column;
    align-items: flex-start;
  }

  .hero-actions .btn-primary,
  .hero-actions .btn-secondary {
    width: 100%;
    text-align: center;
  }

  /* Services */
  .services-grid {
    grid-template-columns: 1fr;
  }

  /* Steps */
  .steps-track {
    grid-template-columns: 1fr;
    gap: clamp(32px, 5vw, 48px);
  }

  /* Software Tools logo grid: 2 columns on mobile */
  .tools-logo-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .tool-logo-item img {
    max-height: 44px;
  }

  /* Contact */
  .contact-actions {
    flex-direction: column;
    align-items: flex-start;
  }

  .contact-actions .btn-ghost {
    width: 100%;
    justify-content: center;
  }

  /* Data requirements */
  .accordion-item summary {
    padding: 16px 0;
  }

  /* Downloads */
  .downloads-grid {
    grid-template-columns: 1fr;
  }

  .download-card {
    flex-direction: column;
    align-items: flex-start;
    gap: 16px;
  }

  /* Footer */
  .footer-inner {
    flex-direction: column;
    align-items: flex-start;
  }

  .footer-meta {
    align-items: flex-start;
  }

}


/* --------------------------------------------------------------------------
   15. Data Acquisition Requirements
   -------------------------------------------------------------------------- */
.data-requirements {
  padding-top: var(--section-pad);
  padding-bottom: var(--section-pad);
  border-bottom: 1px solid var(--gray-light);
}

.data-requirements-header {
  margin-bottom: clamp(40px, 6vw, 64px);
}

.data-requirements-intro {
  font-size: 1rem;
  font-weight: 300;
  color: var(--gray-mid);
  max-width: 560px;
  margin-top: 12px;
}

/* Accordion */
.accordion {
  display: flex;
  flex-direction: column;
  gap: 0;
  border: 1px solid var(--gray-light);
}

.accordion-item {
  border-bottom: 1px solid var(--gray-light);
}

.accordion-item:last-child {
  border-bottom: none;
}

.accordion-trigger {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: clamp(20px, 2.5vw, 28px) clamp(24px, 3vw, 40px);
  cursor: pointer;
  list-style: none;
  background-color: var(--white);
  transition: background-color 0.2s ease;
}

/* Remove default triangle marker */
.accordion-trigger::-webkit-details-marker { display: none; }
.accordion-trigger::marker { display: none; }

.accordion-item[open] .accordion-trigger {
  background-color: var(--bone);
}

.accordion-label {
  font-family: var(--font-display);
  font-size: 1.15rem;
  font-weight: 500;
  color: var(--navy);
}

.accordion-icon {
  font-family: var(--font-mono);
  font-size: 1.2rem;
  color: var(--accent);
  transition: transform 0.2s ease;
  flex-shrink: 0;
  margin-left: 16px;
}

.accordion-item[open] .accordion-icon {
  transform: rotate(45deg);
}

.accordion-body {
  padding: clamp(20px, 2.5vw, 32px) clamp(24px, 3vw, 40px);
  background-color: var(--white);
  border-top: 1px solid var(--gray-light);
}

/* Requirements list */
.requirements-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 10px;
  margin-bottom: 20px;
}

.requirements-list li {
  font-size: 0.92rem;
  font-weight: 300;
  color: var(--navy);
  line-height: 1.6;
  padding-left: 20px;
  position: relative;
}

/* Accent bullet */
.requirements-list li::before {
  content: '—';
  font-family: var(--font-mono);
  color: var(--accent);
  position: absolute;
  left: 0;
  font-size: 0.8rem;
}

.requirements-note {
  font-size: 0.85rem;
  font-weight: 400;
  color: var(--gray-mid);
  font-family: var(--font-mono);
  letter-spacing: 0.02em;
  border-left: 3px solid var(--accent);
  padding-left: 12px;
}


/* --------------------------------------------------------------------------
   16. Downloads
   -------------------------------------------------------------------------- */
.downloads {
  padding-top: var(--section-pad);
  padding-bottom: var(--section-pad);
  border-bottom: 1px solid var(--gray-light);
}

.downloads-header {
  margin-bottom: clamp(40px, 6vw, 64px);
}

/* 2-column card grid on desktop */
.downloads-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: clamp(16px, 2vw, 24px);
}

/* Each download card */
.download-card {
  background-color: var(--white);
  border: 1px solid var(--gray-light);
  padding: clamp(24px, 3vw, 36px);
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 24px;
  transition: border-color 0.2s ease;
}

.download-card:hover {
  border-color: var(--accent);
}

.download-card-info {
  flex: 1;
}

/* File type badge */
.download-file-type {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  font-weight: 500;
  letter-spacing: 0.1em;
  color: var(--accent);
  display: block;
  margin-bottom: 8px;
}

.download-title {
  font-family: var(--font-display);
  font-size: 1.15rem;
  font-weight: 500;
  color: var(--navy);
  margin-bottom: 8px;
  line-height: 1.3;
}

.download-description {
  font-size: 0.88rem;
  font-weight: 300;
  color: var(--gray-mid);
  line-height: 1.6;
}

/* Download button — compact secondary style with icon */
.download-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  white-space: nowrap;
  flex-shrink: 0;
  padding: 10px 20px;
  font-size: 0.85rem;
}


/* --------------------------------------------------------------------------
   17. Page Header — used on sub-pages (data-requirements.html, downloads.html)
   -------------------------------------------------------------------------- */
.page-header {
  padding-top: calc(108px + clamp(48px, 6vw, 80px));
  padding-bottom: clamp(48px, 6vw, 80px);
  border-bottom: 1px solid var(--gray-light);
}

/* Back link — breadcrumb style */
.page-header-back {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 400;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--gray-mid);
  margin-bottom: 32px;
  transition: color 0.2s ease;
}

.page-header-back:hover {
  color: var(--accent);
}

/* Page title — slightly smaller than hero, same family */
.page-header-title {
  font-family: var(--font-display);
  font-size: clamp(2rem, 4vw, 3.2rem);
  font-weight: 300;
  color: var(--navy);
  line-height: 1.15;
  margin-bottom: 20px;
  max-width: 760px;
}

/* Optional intro paragraph beneath the title */
.page-header-intro {
  font-family: var(--font-body);
  font-size: 1rem;
  font-weight: 300;
  color: var(--gray-mid);
  line-height: 1.7;
  max-width: 600px;
}

/* Inline links in step descriptions — subtle accent colour */
.step-description a {
  color: var(--accent);
  text-decoration: underline;
  text-decoration-color: rgba(200, 169, 110, 0.4);
  text-underline-offset: 3px;
  transition: text-decoration-color 0.2s ease;
}

.step-description a:hover {
  text-decoration-color: var(--accent);
}


/* --------------------------------------------------------------------------
   18. Responsive adjustments for 6-item nav — Tablet (≤ 1024px)
   -------------------------------------------------------------------------- */
@media (max-width: 1024px) {

  .nav-links {
    gap: 14px;
  }

  .nav-links a {
    font-size: 0.80rem;
  }

}


/* --------------------------------------------------------------------------
   19. Credibility Strip
   A minimal 4-item strip between the hero and services sections.
   Communicates four key brand facts at a glance.
   -------------------------------------------------------------------------- */
.credibility-strip {
  background-color: var(--white);
  border-bottom: 1px solid var(--gray-light);
  padding: 0;
}

.credibility-items {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 0;
}

.credibility-item {
  padding: clamp(20px, 2.5vw, 28px) clamp(24px, 3vw, 40px);
  border-right: 1px solid var(--gray-light);
  display: flex;
  flex-direction: column;
  gap: 5px;
}

.credibility-item:first-child {
  padding-left: 0;
}

.credibility-item:last-child {
  border-right: none;
  padding-right: 0;
}

.credibility-label {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  font-weight: 400;
  text-transform: uppercase;
  letter-spacing: 0.14em;
  color: var(--gray-mid);
}

.credibility-value {
  font-family: var(--font-body);
  font-size: 0.92rem;
  font-weight: 400;
  color: var(--navy);
  line-height: 1.4;
}


/* --------------------------------------------------------------------------
   20. Why CranioPlan Section
   Two-column: editorial text left, differentiator items right.
   This is the anchor target for the nav link "About CranioPlan".
   -------------------------------------------------------------------------- */
.why-cranioplan {
  padding-top: var(--section-pad);
  padding-bottom: var(--section-pad);
  background-color: var(--white);
  border-bottom: 1px solid var(--gray-light);
}

/* Two-column split: ~40% text / ~60% differentiators */
.why-layout {
  display: grid;
  grid-template-columns: 2fr 3fr;
  gap: clamp(48px, 7vw, 96px);
  align-items: start;
}

/* Left text column — sticky so it stays visible while scrolling differentiators */
.why-text {
  position: sticky;
  top: calc(108px + 48px);
}

.why-intro {
  font-size: 1rem;
  font-weight: 300;
  color: var(--gray-mid);
  line-height: 1.8;
  margin-top: 24px;
  max-width: 420px;
}

/* Right: stacked differentiator items */
.why-differentiators {
  display: flex;
  flex-direction: column;
  gap: 0;
  border-top: 1px solid var(--gray-light);
}

.differentiator-item {
  display: grid;
  grid-template-columns: 56px 1fr;
  gap: 20px;
  align-items: start;
  padding: clamp(24px, 3vw, 36px) 0;
  border-bottom: 1px solid var(--gray-light);
}

.differentiator-number {
  font-family: var(--font-mono);
  font-size: var(--size-label);
  font-weight: 500;
  color: var(--accent);
  letter-spacing: 0.1em;
  padding-top: 3px;
}

.differentiator-content {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.differentiator-title {
  font-family: var(--font-display);
  font-size: 1.2rem;
  font-weight: 500;
  color: var(--navy);
  line-height: 1.3;
}

.differentiator-text {
  font-size: 0.92rem;
  font-weight: 300;
  color: var(--gray-mid);
  line-height: 1.75;
}


/* --------------------------------------------------------------------------
   21. Responsive — Credibility Strip & Why Section (≤ 1024px)
   -------------------------------------------------------------------------- */
@media (max-width: 1024px) {

  /* Credibility: 2-column on tablet */
  .credibility-items {
    grid-template-columns: repeat(2, 1fr);
  }

  .credibility-item:nth-child(2) {
    border-right: none;
    padding-right: 0;
  }

  .credibility-item:nth-child(3) {
    padding-left: 0;
    border-right: 1px solid var(--gray-light);
  }

  .credibility-item:nth-child(4) {
    border-right: none;
    padding-right: 0;
  }

  .credibility-item:nth-child(1),
  .credibility-item:nth-child(2) {
    border-bottom: 1px solid var(--gray-light);
  }

  /* Why layout: stack on tablet */
  .why-layout {
    grid-template-columns: 1fr;
    gap: 40px;
  }

  .why-text {
    position: static;
  }

  .why-intro {
    max-width: 100%;
  }

}


/* --------------------------------------------------------------------------
   22. Responsive — Credibility Strip & Why Section (≤ 768px)
   -------------------------------------------------------------------------- */
@media (max-width: 768px) {

  /* Credibility: 1-column on mobile */
  .credibility-items {
    grid-template-columns: 1fr;
  }

  .credibility-item {
    border-right: none;
    border-bottom: 1px solid var(--gray-light);
    padding-left: 0;
    padding-right: 0;
  }

  .credibility-item:last-child {
    border-bottom: none;
  }

  .credibility-item:nth-child(3) {
    border-right: none;
    padding-left: 0;
  }

  /* Differentiator: tighter column grid on mobile */
  .differentiator-item {
    grid-template-columns: 44px 1fr;
    gap: 14px;
  }

}