/* ==========================================================================
   Layout: containers, sections, nav, footer, grids
   ========================================================================== */

/* ---- Containers ---------------------------------------------------------- */

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

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

/* ---- Sections ------------------------------------------------------------ */

.section {
  padding-block: var(--section-padding);
}

.section--tight {
  padding-block: calc(var(--section-padding) * 0.6);
}

.section--subtle {
  background-color: var(--color-bg-subtle);
}

.section__header {
  max-width: 42rem;
  margin-bottom: var(--space-12);
}

.section__eyebrow {
  display: inline-block;
  font-size: var(--text-sm);
  font-weight: var(--weight-semibold);
  letter-spacing: var(--tracking-wide);
  text-transform: uppercase;
  color: var(--color-accent-text);
  margin-bottom: var(--space-4);
}

.section__title {
  margin-bottom: var(--space-5);
}

/* With no lead paragraph following, the title's own margin would stack on
   top of the header's, leaving too much air above the content. */
.section__title:last-child {
  margin-bottom: 0;
}

.section__lead {
  font-size: var(--text-lg);
  color: var(--color-text-secondary);
  line-height: var(--leading-relaxed);
}

/* ---- Grid ---------------------------------------------------------------- */

.grid {
  display: grid;
  gap: var(--space-6);
}

/* Mobile-first: one column, widening at the breakpoints below. */
@media (min-width: 40rem) {
  .grid--2,
  .grid--3 {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 60rem) {
  .grid--3 {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .grid {
    gap: var(--space-8);
  }
}

/* ---- Site header / nav --------------------------------------------------- */

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background-color: transparent;
  border-bottom: 1px solid transparent;
  transition: background-color var(--duration-base) var(--ease-out),
    border-color var(--duration-base) var(--ease-out),
    backdrop-filter var(--duration-base) var(--ease-out);
}

/* Applied by JS once the page scrolls past the top. */
.site-header.is-scrolled {
  background-color: var(--color-nav-bg);
  border-bottom-color: var(--color-border);
  backdrop-filter: saturate(180%) blur(12px);
  -webkit-backdrop-filter: saturate(180%) blur(12px);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-6);
  height: var(--nav-height);
}

.nav__brand {
  display: inline-flex;
  align-items: center;
  gap: var(--space-3);
  color: var(--color-text);
  font-weight: var(--weight-semibold);
  font-size: var(--text-lg);
  letter-spacing: var(--tracking-snug);
  flex-shrink: 0;
}

.nav__brand:hover {
  color: var(--color-text);
}

.nav__mark {
  display: grid;
  place-items: center;
  width: 2rem;
  height: 2rem;
  border-radius: var(--radius-md);
  background: linear-gradient(
    135deg,
    var(--color-accent) 0%,
    var(--color-accent-active) 100%
  );
  color: #fff;
  font-size: var(--text-sm);
  font-weight: var(--weight-bold);
  letter-spacing: 0;
  transition: transform var(--duration-base) var(--ease-out);
}

.nav__brand:hover .nav__mark {
  transform: rotate(-6deg) scale(1.05);
}

/* Desktop link cluster, hidden on small screens in favor of the drawer. */
.nav__links {
  display: none;
  align-items: center;
  gap: var(--space-1);
  list-style: none;
  margin: 0;
  padding: 0;
}

.nav__link {
  display: block;
  padding: var(--space-2) var(--space-3);
  border-radius: var(--radius-md);
  font-size: var(--text-sm);
  font-weight: var(--weight-medium);
  color: var(--color-text-secondary);
  transition: color var(--duration-fast) var(--ease-out),
    background-color var(--duration-fast) var(--ease-out);
}

.nav__link:hover {
  color: var(--color-text);
  background-color: var(--color-bg-muted);
}

.nav__actions {
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

/* ---- Mobile nav drawer --------------------------------------------------- */

.nav__toggle {
  display: inline-grid;
  place-items: center;
  width: 2.5rem;
  height: 2.5rem;
  border-radius: var(--radius-md);
  color: var(--color-text-secondary);
  transition: color var(--duration-fast) var(--ease-out),
    background-color var(--duration-fast) var(--ease-out);
}

.nav__toggle:hover {
  color: var(--color-text);
  background-color: var(--color-bg-muted);
}

.nav__toggle-bars {
  position: relative;
  width: 1.125rem;
  height: 2px;
  border-radius: var(--radius-full);
  background-color: currentColor;
  transition: background-color var(--duration-fast) var(--ease-out);
}

.nav__toggle-bars::before,
.nav__toggle-bars::after {
  content: "";
  position: absolute;
  left: 0;
  width: 100%;
  height: 100%;
  border-radius: inherit;
  background-color: currentColor;
  transition: transform var(--duration-base) var(--ease-out);
}

.nav__toggle-bars::before {
  transform: translateY(-6px);
}

.nav__toggle-bars::after {
  transform: translateY(6px);
}

/* Bars morph into an X when the drawer is open. */
.nav__toggle[aria-expanded="true"] .nav__toggle-bars {
  background-color: transparent;
}

.nav__toggle[aria-expanded="true"] .nav__toggle-bars::before {
  transform: translateY(0) rotate(45deg);
}

.nav__toggle[aria-expanded="true"] .nav__toggle-bars::after {
  transform: translateY(0) rotate(-45deg);
}

.nav__drawer {
  position: fixed;
  inset: var(--nav-height) 0 auto 0;
  padding: var(--space-4) var(--container-gutter) var(--space-6);
  background-color: var(--color-bg);
  border-bottom: 1px solid var(--color-border);
  box-shadow: var(--shadow-md);
  transform: translateY(-8px);
  opacity: 0;
  visibility: hidden;
  transition: opacity var(--duration-base) var(--ease-out),
    transform var(--duration-base) var(--ease-out),
    visibility var(--duration-base);
}

.nav__drawer.is-open {
  transform: translateY(0);
  opacity: 1;
  visibility: visible;
}

.nav__drawer-list {
  display: flex;
  flex-direction: column;
  gap: var(--space-1);
  list-style: none;
  margin: 0;
  padding: 0;
}

.nav__drawer-link {
  display: block;
  padding: var(--space-3) var(--space-3);
  border-radius: var(--radius-md);
  font-size: var(--text-base);
  font-weight: var(--weight-medium);
  color: var(--color-text-secondary);
  transition: color var(--duration-fast) var(--ease-out),
    background-color var(--duration-fast) var(--ease-out);
}

.nav__drawer-link:hover {
  color: var(--color-text);
  background-color: var(--color-bg-muted);
}

.nav__drawer .btn {
  width: 100%;
  margin-top: var(--space-4);
}

@media (min-width: 48rem) {
  .nav__links {
    display: flex;
  }

  .nav__toggle,
  .nav__drawer {
    display: none;
  }
}

/* ---- Footer -------------------------------------------------------------- */

.site-footer {
  border-top: 1px solid var(--color-border);
  background-color: var(--color-bg-subtle);
  padding-block: var(--space-16) var(--space-8);
}

.footer__top {
  display: grid;
  gap: var(--space-10);
  padding-bottom: var(--space-12);
}

@media (min-width: 48rem) {
  .footer__top {
    /* Brand block on the left, link column pushed to the right edge. */
    grid-template-columns: minmax(0, 1fr) auto;
    gap: var(--space-16);
  }
}

.footer__blurb {
  margin-top: var(--space-4);
  max-width: 28rem;
  font-size: var(--text-sm);
  color: var(--color-text-secondary);
}

.footer__email {
  display: inline-block;
  margin-top: var(--space-4);
  font-size: var(--text-sm);
  font-weight: var(--weight-medium);
  color: var(--color-text-secondary);
  border-bottom: 1px solid var(--color-border-strong);
  padding-bottom: 1px;
  transition: color var(--duration-fast) var(--ease-out),
    border-color var(--duration-fast) var(--ease-out);
}

.footer__email:hover {
  color: var(--color-accent-text);
  border-bottom-color: currentColor;
}

.footer__heading {
  font-size: var(--text-xs);
  font-weight: var(--weight-semibold);
  letter-spacing: var(--tracking-wide);
  text-transform: uppercase;
  color: var(--color-text-muted);
  margin-bottom: var(--space-4);
}

/* Few enough links to read as a single row; wraps on narrow screens. The
   row gap only applies once wrapping happens. */
.footer__list {
  display: flex;
  flex-flow: row wrap;
  gap: var(--space-3) var(--space-6);
  list-style: none;
  margin: 0;
  padding: 0;
}

.footer__link {
  font-size: var(--text-sm);
  color: var(--color-text-secondary);
}

.footer__link:hover {
  color: var(--color-text);
}

.footer__bottom {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-4);
  padding-top: var(--space-8);
  border-top: 1px solid var(--color-border);
  font-size: var(--text-sm);
  color: var(--color-text-muted);
}