/* ============================
   Top Navigation
============================ */

.top-nav {
  position: sticky;
  top: 0;
  z-index: 20;

  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);

  background: color-mix(
    in srgb,
    var(--panel) 85%,
    transparent
  );

  border-bottom: 1px solid var(--border-subtle);
}

nav {
  position: sticky;
  top: 0;
  z-index: 10;

  background: color-mix(
    in srgb,
    var(--panel) 88%,
    transparent
  );

  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);

  padding: 1rem 2rem;
  align-items: center;
  grid-template-columns: auto minmax(0, 1fr) auto;
}


nav ul {
      list-style: none;
      display: flex;
      grid-gap: 1.5rem;
      margin: 0;
      padding: 0;
    }

nav a {
  color: var(--text);
  text-decoration: none;
  position: relative;
  padding-bottom: 2px;
}

nav a::after {
      content: "";
      position: absolute;
      left: 0;
      bottom: 0;
      width: 0;
      height: 2px;
      background: linear-gradient(90deg, var(--accent), var(--accent-warm));
      transition: width 0.3s ease;
    }

    nav a:hover::after,
    nav a.active::after {
      width: 100%;
    }


.nav-inner {
  display: grid;
  align-items: center;
  padding: 0.75rem 1.5rem;
  max-width: 1000px;
  margin: 0 auto;
  grid-template-columns: 1fr auto 1fr;
  grid-column: 2;
}

.nav-brand {
  display: flex;
  align-items: center;
  grid-gap: 0.6rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  color: var(--text);
  text-decoration: none;

  transition:
    opacity var(--hover-duration) var(--hover-ease),
    transform var(--hover-duration) var(--hover-ease);
}

.nav-brand:hover {
  opacity: 0.85;
}
.nav-brand::after {
  content: none;
}

.logo {
  display: flex;
  align-items: center;
}
.nav .logo {
  width: 26px;
  height: 26px;
}

.site-logo {
  width: 48px;
  height: 48px;
  display: block;
}

.site-logo .logo-accent {
  fill: var(--logo-accent);
}

.site-logo .logo-accent-dark {
  fill: var(--logo-accent-dark);
}

.site-logo .logo-accent-warm {
  fill: var(--accent-warm);
}

.site-logo .logo-accent-warm-dark {
  fill: var(--accent-warm-dark);
}

/* Optional subtle hover polish */
.nav-brand:hover .site-logo {
  filter: drop-shadow(0 0 10px var(--accent-glow));
}

.nav-links {
  display: grid;
  justify-content: center;
  grid-auto-flow: column;
  list-style: none;
  grid-gap: 2rem;
}

.nav-links li a {
  position: relative;
  text-decoration: none;
  color: var(--text);
  font-size: 0.85rem;
  opacity: 0.85;
  padding: 0.3rem 0;
  transition: opacity var(--hover-duration) var(--hover-ease),
              transform var(--hover-duration) var(--hover-ease);
}

.nav-links li a[aria-current="true"],
.nav-links li a[aria-current="true"] {
      opacity: 1;
    }

.nav-links li a:hover {
  opacity: 1;
  transform: translateY(-1px);
}

.nav-links li a::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -4px;
  width: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--accent), var(--accent-warm));
  transition: width 0.25s ease;
}

.nav-links li a:hover::after,
.nav-links li a[aria-current="true"]::after {
  width: 100%;
}

.nav-actions {
  justify-self: end;
  display: grid;
  grid-auto-flow: column;
  grid-gap: .5rem;
}

.theme-toggle, .nav-toggle, .search-toggle {
  background: transparent;
  border: 2px solid var(--accent-dark);
  border-radius: 999px;
  font-size: 1rem;
  color: var(--text);
  cursor: pointer;
  transition: box-shadow 0.25s ease, transform 0.25s ease;
  width: 40px;
  height: 40px;
  padding: 5px;
  display: grid;
  place-items: center;
  position: relative;
}

.search-toggle {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  text-decoration: none;
  box-sizing: border-box;
  line-height: 1;
}

.search-toggle::after {
  content: none;
}

.search-toggle svg {
  width: 20px;
  height: 20px;
}

/* active search state change */
.theme-toggle[aria-pressed="false"],
.search-toggle[aria-current="true"],
.nav-toggle[aria-expanded="true"] {
  border-color: var(--accent);
  box-shadow:
    0 0 0 2px var(--border-soft),
    0 0 16px var(--border-soft);
}
/* pressed state */
.theme-toggle[aria-pressed="true"],
.search-toggle[aria-current="true"],
.nav-toggle[aria-expanded="true"] {
  transform: translateY(0); /* cancel hover lift */
}
/* icon colour */
.theme-toggle[aria-pressed="false"] svg,
.search-toggle[aria-current="true"] svg,
.nav-toggle[aria-expanded="true"] svg {
  color: var(--accent);
}

.search-toggle[aria-current="true"] svg {
  color: var(--accent);
  transform: none;
}

.nav-toggle {
  display: none;
}

.theme-toggle:hover, .nav-toggle:hover, .search-toggle:hover, .search-toggle:focus {
  transform: translateY(-1px);
  box-shadow: 0 0 0 2px var(--border-soft),
              0 0 16px var(--border-soft);
}
    
.theme-icon {
  width: 20px;
  height: 20px;
  position: absolute;
  transition:
    opacity 200ms ease,
    transform 260ms cubic-bezier(.2,.8,.2,1);
}

/* light mode */
.theme-icon.sun {
  opacity: 1;
  transform: rotate(0deg) scale(1);
}

.theme-icon.moon {
  opacity: 0;
  transform: rotate(-90deg) scale(0.6);
}

/* dark mode */
:root[data-theme="dark"] .theme-icon.sun {
  opacity: 0;
  transform: rotate(90deg) scale(0.6);
}

:root[data-theme="dark"] .theme-icon.moon {
  opacity: 1;
  transform: rotate(0deg) scale(1);
}

/* Small device tweaks */
@media (max-width: 410px) {
  .nav-inner {
    padding: 0.25rem 0.5rem;
  }
}

/* Mobile */
@media (max-width: 768px) {
  nav {
    padding: 0;
  }
  .nav-inner {
    grid-template-columns: auto auto;
  }
  .nav-brand {
    grid-column: 1;
  }
  .nav-links {
    grid-column: 1 / -1;
    grid-auto-flow: row;
    justify-self: stretch;
    grid-auto-rows: min-content;
    grid-gap: 1rem;
    margin-top: 0.75rem;
    padding: 1rem 0;
    border-top: 1px solid var(--border-subtle);
    opacity: 0;
    transform: translateY(-8px);
    pointer-events: none;
    transition: opacity 220ms ease, transform 220ms ease;
    display: none;
  }

  .nav-links.open {
    opacity: 1;
    transform: translateY(0);
    pointer-events: auto;
    display: grid;
  }
  .nav-actions {
    grid-column: 2;
    grid-row: 1;
  }
  .theme-toggle, 
  .nav-toggle, 
  .search-button {
    display: inline-flex;
    align-items: center;
    justify-content: center;
  }
  
}

@media (prefers-reduced-motion: reduce) {
  .nav-links {
    transition: none;
  }
  .theme-toggle,
  .search-toggle,
  .nav-toggle {
    transition: none;
    transform: none;
  }
}