/* ==========================================================================
   Key-Cert — Layout
   Containers, section rhythm, grid scaffolding, header/footer structure,
   the audit rail.
   ========================================================================== */

.container {
  max-width: var(--container-max);
  width: 100%;
  min-width: 0;
  margin-inline: auto;
  padding-inline: var(--container-pad);
}

.container--wide {
  max-width: var(--container-wide);
}

/* Section rhythm — set once here. Do not override in a component class. */
.section {
  padding-block: var(--section-pad);
  position: relative;
}

.section--white   { background: var(--kc-white); }
.section--mist    { background: var(--kc-mist); }
.section--marine  {
  background: var(--kc-gradient-marine);
  color: var(--kc-white);
}
.section--marine h2,
.section--marine h3,
.section--marine p { color: var(--kc-white); }

.section-head {
  max-width: 68ch;
  margin-bottom: var(--space-48);
}

.section-head h2 {
  margin-top: var(--space-12);
}

.section-head--split {
  display: flex;
  flex-wrap: wrap;
  align-items: flex-end;
  justify-content: space-between;
  gap: var(--space-24);
  max-width: none;
}

/* ---- grid scaffolding ---- */
.grid {
  display: grid;
  gap: var(--space-32);
}

.grid--cards {
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
}

.grid--2 { grid-template-columns: repeat(2, 1fr); }
.grid--3 { grid-template-columns: repeat(3, 1fr); }
.grid--4 { grid-template-columns: repeat(4, 1fr); }

@media (max-width: 900px) {
  .grid--2, .grid--3, .grid--4 {
    grid-template-columns: 1fr;
  }
}

@media (min-width: 601px) and (max-width: 900px) {
  .grid--3, .grid--4 {
    grid-template-columns: repeat(2, 1fr);
  }
}

/* ==========================================================================
   Header
   ========================================================================== */

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  height: var(--header-height);
  background: var(--kc-white);
  border-bottom: 1px solid var(--kc-line);
  display: flex;
  align-items: center;
  transition: box-shadow var(--motion-fast) var(--ease);
}

.site-header.is-scrolled {
  box-shadow: 0 4px 16px rgba(6, 42, 67, 0.08);
}

.site-header__inner {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-24);
}

.brand {
  display: flex;
  align-items: center;
  gap: var(--space-12);
  text-decoration: none;
  flex-shrink: 0;
}

.brand__mark {
  height: 40px;
  width: auto;
}

.brand__word {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 1.25rem;
  letter-spacing: -0.01em;
  color: var(--kc-marine);
}

/* primary nav */
.primary-nav {
  display: flex;
  align-items: center;
  gap: var(--space-32);
}

.primary-nav__list {
  display: flex;
  align-items: center;
  gap: var(--space-16);
}

.primary-nav__link {
  position: relative;
  display: inline-flex;
  align-items: center;
  height: var(--header-height);
  font-family: var(--font-mono);
  font-size: 11.5px;
  font-weight: 500;
  letter-spacing: .03em;
  text-transform: uppercase;
  color: var(--kc-ink);
  text-decoration: none;
  border-bottom: 2px solid transparent;
}

.primary-nav__link:hover {
  color: var(--kc-blue-deep);
}

.primary-nav__link[aria-current="page"] {
  color: var(--kc-marine);
  border-bottom-color: var(--kc-seal);
}

.primary-nav__item {
  position: relative;
  display: flex;
  align-items: center;
  flex-shrink: 0;
}

.primary-nav__cta {
  display: none;
}

.primary-nav__trigger {
  display: inline-flex;
  align-items: center;
  gap: var(--space-4);
  background: none;
  border: none;
  height: var(--header-height);
  font-family: var(--font-mono);
  font-size: 11.5px;
  font-weight: 500;
  letter-spacing: .03em;
  text-transform: uppercase;
  color: var(--kc-ink);
  border-bottom: 2px solid transparent;
}

.primary-nav__trigger:hover { color: var(--kc-blue-deep); }

.primary-nav__trigger[aria-expanded="true"] {
  color: var(--kc-marine);
  border-bottom-color: var(--kc-seal);
}

.primary-nav__caret {
  width: 9px;
  height: 9px;
  transition: transform var(--motion-fast) var(--ease);
}

.primary-nav__trigger[aria-expanded="true"] .primary-nav__caret {
  transform: rotate(180deg);
}

.dropdown-panel {
  position: absolute;
  top: 100%;
  left: 50%;
  transform: translateX(-50%);
  min-width: 260px;
  background: var(--kc-white);
  border: 1px solid var(--kc-line);
  border-radius: var(--radius);
  box-shadow: 0 12px 32px rgba(6, 42, 67, 0.14);
  padding: var(--space-12);
  display: grid;
  gap: 2px;
}

.dropdown-panel[hidden] { display: none; }

.dropdown-panel a {
  display: block;
  padding: var(--space-8) var(--space-12);
  border-radius: 2px;
  text-decoration: none;
  color: var(--kc-ink);
  font-size: var(--step-small);
}

.dropdown-panel a:hover,
.dropdown-panel a:focus-visible {
  background: var(--kc-mist);
  color: var(--kc-blue-deep);
}

.dropdown-panel .scheme-code {
  display: block;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .06em;
  color: var(--kc-slate);
  margin-top: 2px;
}

.header-actions {
  display: flex;
  align-items: center;
  gap: var(--space-16);
}

.menu-toggle {
  display: none;
  align-items: center;
  gap: var(--space-8);
  background: none;
  border: 1px solid var(--kc-line);
  border-radius: var(--radius);
  padding: var(--space-8) var(--space-12);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .08em;
  text-transform: uppercase;
}

.menu-toggle__icon {
  width: 18px;
  height: 14px;
  position: relative;
}

.menu-toggle__icon span,
.menu-toggle__icon::before,
.menu-toggle__icon::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  height: 2px;
  background: var(--kc-ink);
}

.menu-toggle__icon::before { top: 0; }
.menu-toggle__icon span { top: 6px; }
.menu-toggle__icon::after { top: 12px; }

@media (max-width: 1024px) {
  .primary-nav__list,
  .primary-nav > .primary-nav__list { display: none; }
  .menu-toggle { display: inline-flex; }

  .primary-nav {
    position: fixed;
    inset: var(--header-height) 0 0 0;
    background: var(--kc-white);
    flex-direction: column;
    align-items: stretch;
    justify-content: flex-start;
    padding: var(--space-24) var(--container-pad);
    overflow-y: auto;
    transform: translateX(100%);
    transition: transform var(--motion-med) var(--ease);
    z-index: 99;
  }

  .primary-nav.is-open { transform: translateX(0); }

  .primary-nav__list {
    display: flex !important;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    width: 100%;
  }

  .primary-nav__item {
    justify-content: space-between;
    border-bottom: 1px solid var(--kc-line);
  }

  .primary-nav__item:has(.dropdown-panel) {
    flex-wrap: wrap;
  }

  .primary-nav__link,
  .primary-nav__trigger {
    height: auto;
    width: auto;
    flex: 1 1 auto;
    padding: var(--space-16) 0;
    border-bottom: none;
    justify-content: flex-start;
  }

  .primary-nav__trigger {
    flex: 0 0 auto;
    justify-content: flex-end;
    padding-left: var(--space-16);
  }

  .primary-nav__item:has(.dropdown-panel) .dropdown-panel {
    flex-basis: 100%;
  }

  .dropdown-panel {
    position: static;
    transform: none;
    box-shadow: none;
    border: none;
    border-left: 2px solid var(--kc-line);
    margin: 0 0 var(--space-8) var(--space-12);
    padding-left: var(--space-16);
  }

  .primary-nav__cta {
    display: block;
    margin-top: auto;
    padding-top: var(--space-24);
    position: sticky;
    bottom: 0;
    background: var(--kc-white);
  }

  .primary-nav__cta .btn { width: 100%; }

  .header-actions .btn--seal { display: none; }

  @media (prefers-reduced-motion: reduce) {
    .primary-nav { transition: none; }
  }
}

/* ==========================================================================
   Audit rail — signature element, ≥1024px only
   ========================================================================== */

.audit-rail {
  display: none;
}

@media (min-width: 1024px) {
  .audit-rail {
    display: block;
    position: absolute;
    left: clamp(20px, 3vw, 40px);
    top: 0;
    bottom: 0;
    width: 2px;
    background: var(--kc-line);
    z-index: 1;
  }

  .audit-rail__fill {
    position: sticky;
    top: var(--header-height);
    width: 2px;
    height: calc(100vh - var(--header-height));
    background: var(--kc-blue);
    opacity: .35;
  }

  main {
    position: relative;
  }

  .section[data-rail-step]::before {
    counter-reset: none;
    content: attr(data-rail-step);
    position: absolute;
    left: clamp(20px, 3vw, 40px);
    top: var(--space-64);
    transform: translateX(-50%);
    width: 26px;
    height: 26px;
    background: var(--kc-white);
    border: 2px solid var(--kc-blue);
    color: var(--kc-marine);
    font-family: var(--font-mono);
    font-size: 11px;
    letter-spacing: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 2;
  }
}

/* ==========================================================================
   Footer
   ========================================================================== */

.site-footer {
  background: var(--kc-marine);
  color: var(--kc-white);
  padding-block: var(--space-96) var(--space-32);
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr repeat(3, 1fr);
  gap: var(--space-32);
  padding-bottom: var(--space-64);
  border-bottom: 1px solid rgba(255,255,255,.14);
}

@media (max-width: 900px) {
  .footer-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 560px) {
  .footer-grid {
    grid-template-columns: 1fr;
  }
}

.footer-brand {
  display: flex;
  align-items: center;
  gap: var(--space-12);
  margin-bottom: var(--space-16);
  text-decoration: none;
}

.footer-brand__mark {
  height: 48px;
  width: auto;
}

.footer-brand__word {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 1.25rem;
  color: var(--kc-white);
}

.footer-col__heading {
  color: var(--kc-white);
  font-size: 13px;
  font-family: var(--font-mono);
  letter-spacing: .1em;
  text-transform: uppercase;
  font-weight: 500;
  margin-bottom: var(--space-16);
}

.footer-col ul { display: grid; gap: var(--space-8); }

.footer-col a {
  color: rgba(255,255,255,.78);
  text-decoration: none;
  font-size: var(--step-small);
}

.footer-col a:hover { color: var(--kc-white); text-decoration: underline; }

.footer-legal {
  padding-top: var(--space-24);
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-16) var(--space-24);
  justify-content: space-between;
  align-items: center;
  font-size: 13px;
  color: rgba(255,255,255,.64);
}

.footer-legal__links {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-16);
}

.footer-legal a {
  color: rgba(255,255,255,.64);
}