/* ==========================================================================
   Layout v2 — masthead header / footer
   Header now shares the exact same .container width as page content
   (previous version floated at a narrower width — that mismatch is fixed).
   ========================================================================== */

/* ---- Site header: full-width masthead, not a floating pill ---- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 500;
  background: var(--bg-base);
  border-bottom: var(--rule-thick, 2px solid var(--ink-950));
  border-bottom-color: var(--text-primary);
}

.header-inner {
  max-width: var(--container);
  margin-inline: auto;
  padding-inline: var(--gutter);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--sp-3);
  padding-block: 1.1rem;
}

.brand {
  display: flex;
  align-items: center;
  gap: .7rem;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.3rem;
  white-space: nowrap;
}
.brand-mark {
  width: 40px; height: 40px;
  border: 2px solid var(--text-primary);
  border-radius: 50%;
  display: grid; place-items: center;
  color: var(--text-primary);
  font-family: var(--font-display);
  font-size: 1.05rem;
}

.main-nav { display: flex; }
.main-nav ul { display: flex; align-items: center; gap: .1rem; }
.main-nav a {
  display: inline-block;
  padding: .5rem .9rem;
  font-size: .92rem;
  color: var(--text-secondary);
  border-bottom: 2px solid transparent;
  transition: color var(--dur-fast) ease, border-color var(--dur-fast) ease;
}
.main-nav a:hover,
.main-nav a[aria-current="page"] {
  color: var(--text-primary);
  border-color: var(--accent);
}

.header-actions { display: flex; align-items: center; gap: .6rem; }

.theme-toggle {
  width: 42px; height: 42px;
  border-radius: 50%;
  border: 1px solid var(--border-strong);
  display: grid; place-items: center;
  background: var(--bg-raised);
  transition: background var(--dur-fast) ease;
  position: relative;
  overflow: hidden;
}
.theme-toggle:hover { background: var(--accent-soft); }
.theme-icon {
  position: absolute;
  inset: 0;
  display: grid;
  place-items: center;
  transition: transform var(--dur-slow) var(--ease-editorial), opacity var(--dur-med) ease;
}
.theme-icon svg { width: 18px; height: 18px; }
/* Light theme (default): sun visible, moon hidden above it */
.icon-sun  { opacity: 1; transform: rotate(0deg) scale(1); }
.icon-moon { opacity: 0; transform: rotate(70deg) scale(.5); }
/* Dark theme: swap them with a gentle rotate + fade */
[data-theme="dark"] .icon-sun  { opacity: 0; transform: rotate(-70deg) scale(.5); }
[data-theme="dark"] .icon-moon { opacity: 1; transform: rotate(0deg) scale(1); }

.nav-toggle {
  display: none;
  width: 42px; height: 42px;
  border-radius: 50%;
  border: 1px solid var(--border-strong);
  background: var(--bg-raised);
  position: relative;
}
.nav-toggle span, .nav-toggle span::before, .nav-toggle span::after {
  content: "";
  position: absolute;
  width: 18px;
  height: 1.5px;
  background: var(--text-primary);
  transition: transform var(--dur-fast) ease, opacity var(--dur-fast) ease;
  -webkit-transition: transform var(--dur-fast) ease, opacity var(--dur-fast) ease;
  -moz-transition: transform var(--dur-fast) ease, opacity var(--dur-fast) ease;
  -ms-transition: transform var(--dur-fast) ease, opacity var(--dur-fast) ease;
  -o-transition: transform var(--dur-fast) ease, opacity var(--dur-fast) ease;
  right: 50%;
  transform: translateX(50%);
  -webkit-transform: translateX(50%);
  -moz-transform: translateX(50%);
  -ms-transform: translateX(50%);
  -o-transform: translateX(50%);
}
.nav-toggle span { top: 20px; }
.nav-toggle span::before { top: -6px; }
.nav-toggle span::after { top: 6px; }

@media (max-width: 880px) {
  .main-nav {
    position: fixed; inset: 74px var(--gutter) auto var(--gutter);
    background: var(--bg-raised);
    border: 2px solid var(--text-primary);
    padding: var(--sp-3);
    transform: translateY(-10px);
    opacity: 0;
    visibility: hidden;
    transition: all var(--dur-med) var(--ease-editorial);
  }
  .main-nav.is-open { transform: translateY(0); opacity: 1; visibility: visible; }
  .main-nav ul { flex-direction: column; align-items: stretch; width: 100%; }
  .main-nav a { display: block; padding: .8rem .2rem; border-bottom: 1px solid var(--border); }
  .nav-toggle { display: block; }
}

/* ---- Footer: masthead echo at the bottom ---- */
/* ---- Footer: boxed to the same width as the rest of the site content
   (previously the outer background/border spanned the full viewport while
   the site's other bordered blocks stop at the container edge — mismatch) ---- */
.site-footer {
  margin-inline: auto;
  margin-top: var(--sp-7);
  border-top: 2px solid var(--text-primary);
  background: var(--bg-base);
  padding-block: var(--sp-5) var(--sp-4);
}
.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1.1fr;
  gap: var(--sp-4);
}
@media (max-width: 880px) {
  .footer-grid { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 560px) {
  .footer-grid { grid-template-columns: 1fr; }
}
.footer-col h4 {
  font-size: var(--fs-small);
  text-transform: uppercase;
  letter-spacing: .1em;
  color: var(--text-muted);
  margin-bottom: var(--sp-3);
  font-family: var(--font-mono);
  font-weight: 500;
}
.footer-col a, .footer-col li { color: var(--text-secondary); font-size: .95rem; }
.footer-col li + li { margin-top: .7rem; }
.footer-col a:hover { color: var(--accent); }

.footer-bottom {
  margin-top: var(--sp-5);
  padding-top: var(--sp-3);
  border-top: 1px solid var(--border);
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: var(--sp-2);
  font-size: var(--fs-small);
  color: var(--text-muted);
}
.social-row { display: flex; gap: .6rem; }
.social-row a {
  width: 38px; height: 38px;
  border-radius: 50%;
  border: 1px solid var(--border-strong);
  display: grid; place-items: center;
  transition: border-color var(--dur-fast) ease, background var(--dur-fast) ease;
}
.social-row a:hover { background: var(--accent); border-color: var(--accent); color: var(--accent-ink); }

/* ---- Back to top ---- */
#back-to-top {
  position: fixed;
  bottom: var(--sp-4);
  inset-inline-end: var(--sp-4);
  width: 48px; height: 48px;
  border-radius: 50%;
  background: var(--text-primary);
  color: var(--bg-base);
  display: grid; place-items: center;
  opacity: 0; visibility: hidden; transform: translateY(10px);
  transition: all var(--dur-med) var(--ease-editorial);
  z-index: 400;
  border: none;
}
#back-to-top.is-visible { opacity: 1; visibility: visible; transform: translateY(0); }