/* Layout: nav, banner, footer, page shells and the home grid. */

/* ---- Site nav: wordmark, uppercase links and italic-red featured-program
 * entries (Pupper with a photo badge, Build-A-ROSBot). ---- */
.site-nav {
  background: var(--header-bg);
  border-bottom: var(--rule);
  padding: 0.9rem 1.5rem;
  position: sticky;
  top: 0;
  z-index: 100;
}

.site-nav__inner {
  max-width: 1280px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
  flex-wrap: wrap;
}

.site-nav__brand {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  text-decoration: none;
  flex-shrink: 0;
}

.site-nav__logo {
  height: 26px;
  width: 26px;
  display: block;
}

/* Hand-drawn mark is solid dark ink on transparent - invert to white for
   dark mode instead of shipping a second asset. */
:root[data-theme="dark"] .site-nav__logo {
  filter: invert(1);
}

.site-nav__wordmark {
  font-weight: 900;
  font-size: 1.7rem;
  letter-spacing: -0.02em;
  text-transform: uppercase;
  color: var(--text);
  white-space: nowrap;
}

.site-nav__links {
  display: flex;
  align-items: center;
  gap: 1.25rem;
  flex-wrap: wrap;
}

.site-nav__link {
  font-weight: 800;
  text-transform: uppercase;
  font-size: var(--fs-md);
  letter-spacing: 0.02em;
  color: var(--text);
  text-decoration: none;
  border-bottom: 2px solid transparent;
  padding-bottom: 2px;
}

.site-nav__link:hover,
.site-nav__link.active,
.site-nav__featured-link.active {
  border-color: var(--primary);
}

.site-nav__featured-link {
  font-style: italic;
  font-weight: 600;
  font-size: var(--fs-md);
  color: var(--primary);
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  border-bottom: 2px solid transparent;
  padding-bottom: 2px;
}

.site-nav__pupper-photo {
  width: 26px;
  height: 26px;
  border-radius: 999px;
  object-fit: cover;
  border: 2px solid var(--primary);
}

.theme-toggle-btn {
  width: 36px;
  height: 36px;
  border-radius: 999px;
  border: var(--rule);
  background: var(--bg);
  color: var(--text);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: var(--fs-base);
  cursor: pointer;
  transition: background 0.2s ease, border-color 0.2s ease;
  flex-shrink: 0;
}

.theme-toggle-btn:hover {
  border-color: var(--primary);
  color: var(--primary);
}

.theme-toggle-btn__icon {
  display: none;
  width: 18px;
  height: 18px;
}

.theme-toggle-btn__icon svg {
  width: 100%;
  height: 100%;
}

/* Shows the moon in light mode (prompting a switch to dark), the sun in
   dark mode - matches the icon's meaning to what clicking it will do. */
:root:not([data-theme="dark"]) .theme-toggle-btn__icon--moon {
  display: block;
}

:root[data-theme="dark"] .theme-toggle-btn__icon--sun {
  display: block;
}

@media (max-width: 980px) {
  .site-nav {
    position: static;
  }
}

@media (max-width: 620px) {
  .site-nav {
    padding: 0.6rem 1rem;
  }

  .site-nav__inner {
    gap: 0.5rem 1rem;
  }

  .site-nav__wordmark {
    font-size: var(--fs-lg);
  }

  .site-nav__links {
    gap: 0.25rem 0.75rem;
  }

  .site-nav__link {
    font-size: var(--fs-sm);
  }
}

/* ---- Banner: full-width photo with overlaid title ---- */
.banner-header {
  width: 100%;
}

.banner {
  width: 100%;
  height: 204px;
  background-color: #1a1a1a;
  background-size: cover;
  background-position: center;
  text-align: center;
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
}

.banner > div {
  position: relative;
  z-index: 1;
}

.banner h1 {
  color: white;
  text-shadow: 2px 2px 4px black;
}

.banner p {
  color: white;
  text-shadow: 1px 1px 2px black;
  font-size: var(--fs-xl);
  line-height: 1.4;
  letter-spacing: 0.05em;
}

/* ---- Page shells (layouts/home.html, page.html and detail.html) ---- */
.page-content {
  max-width: 1220px;
  margin: 0 auto;
  padding: 1rem 1.5rem 3rem;
}

/* Short intro above a page's main content */
.page-intro {
  padding: 0.75rem 1.5rem;
  margin: 0;
  text-align: center;
  color: var(--text-muted);
}

.page-intro__inner {
  max-width: 70rem;
  margin: 0 auto;
  padding: 0 1.5rem;
}

.page-intro p {
  margin-bottom: 0.75rem;
}

.page-intro *:last-child {
  margin-bottom: 0;
}

.detail-page {
  max-width: 760px;
  margin: 0 auto;
  padding: 2rem 1.5rem 3rem;
}

.detail-page:has(.detail-brief-layout) {
  max-width: 920px;
}

.detail-back {
  margin-top: 2.5rem;
  padding-top: 1.5rem;
  border-top: var(--rule);
}

/* ---- Home page news and rail columns ---- */
.home-grid {
  display: grid;
  grid-template-columns: 1fr 340px;
  gap: 3rem;
}

@media (max-width: 980px) {
  .home-grid {
    grid-template-columns: 1fr;
  }
}

/* ---- Footer ---- */
footer {
  width: 100%;
  padding: 2rem 1rem;
  margin: 3rem 0 0;
  text-align: center;
  background: linear-gradient(to bottom, transparent, var(--bg));
  border-top: var(--rule);
  color: var(--text-muted);
}

footer p {
  margin: 0;
  font-size: var(--fs-sm);
}