/**
 * Shared site navigation — link from every HTML page:
 * <link rel="stylesheet" href="nav.css">
 */
:root {
  --nav-bg: #1f3e59;
  --nav-bar-height: 64px;
  --nav-pad-x: 24px;
  --nav-inner-max: 1280px;
  --nav-brand-size: 19px;
  --nav-link-size: 14px;
  --nav-link-pad-y: 7px;
  --nav-link-pad-x: 14px;
  --nav-brand-pad-y: 7px;
  --nav-brand-pad-x: 3px;
  --nav-link-gap: 8px;
}

.navbar,
.top-nav {
  background-color: var(--nav-bg);
  box-shadow: 0 1px 0 rgba(0, 0, 0, 0.12);
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: var(--nav-bar-height);
  min-height: var(--nav-bar-height);
  z-index: 1000;
  padding: 0 var(--nav-pad-x);
  display: flex;
  align-items: center;
  box-sizing: border-box;
  backdrop-filter: none;
  /* Isolate nav from page-level typography (Tailwind preflight, body line-height, etc.). */
  font-family: Inter, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

.navbar-inner {
  width: 100%;
  max-width: var(--nav-inner-max);
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  position: relative;
  height: 100%;
}

/* Pages without Tailwind still use class="flex items-center" — those utilities do nothing,
   so the brand column must be defined here to match Tailwind-driven pages (index, about, …). */
.navbar-inner > div:first-child {
  flex: 0 0 auto;
  display: flex;
  align-items: center;
  height: 100%;
}

/* Case-study pages: fixed nav is out of flow; push hero so it starts below the bar like other layouts. */
body > nav.navbar + .project-hero {
  margin-top: var(--nav-bar-height);
}

.navbar-center-links {
  position: absolute;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  align-items: center;
  gap: var(--nav-link-gap);
  height: 100%;
}

.nav-links {
  list-style: none;
  display: flex;
  gap: var(--nav-link-gap);
  align-items: center;
  position: absolute;
  left: 50%;
  transform: translateX(-50%);
  margin: 0;
  padding: 0;
  height: 100%;
}

.navbar-brand,
.logo {
  color: #ffffff;
  font-weight: 700;
  text-decoration: none;
  padding: var(--nav-brand-pad-y) var(--nav-brand-pad-x);
  font-size: var(--nav-brand-size);
  letter-spacing: 0.01em;
  line-height: 1;
}

.navbar-brand:hover,
.logo:hover {
  color: #ffffff;
}

.navbar-link {
  color: #d2e1ec;
  font-weight: 500;
  padding: var(--nav-link-pad-y) var(--nav-link-pad-x);
  border-radius: 0.3rem;
  font-size: var(--nav-link-size);
  line-height: 1;
  display: inline-flex;
  align-items: center;
  text-decoration: none;
  transition: background-color 0.2s ease-in-out, color 0.2s ease-in-out;
}

.nav-links a {
  color: #d2e1ec;
  text-decoration: none;
  font-size: var(--nav-link-size);
  font-weight: 500;
  line-height: 1;
  padding: var(--nav-link-pad-y) var(--nav-link-pad-x);
  border-radius: 0.3rem;
  transition: background-color 0.2s ease-in-out, color 0.2s ease-in-out;
  display: inline-flex;
  align-items: center;
}

.navbar-link:hover,
.nav-links a:hover {
  background-color: rgba(255, 255, 255, 0.1);
  color: #ffffff;
}

.navbar-link.active,
.nav-links a.active {
  background-color: rgba(255, 255, 255, 0.16);
  color: #ffffff;
  font-size: var(--nav-link-size);
}

.navbar-link.active:hover {
  background-color: rgba(255, 255, 255, 0.2);
}

@media (max-width: 900px) {
  .navbar,
  .top-nav {
    /* Mobile: keep nav fully in-flow so it never overlays hero/header content. */
    position: relative;
    top: auto;
    left: auto;
    height: auto;
    min-height: var(--nav-bar-height);
    padding: 10px var(--nav-pad-x);
  }

  /* On mobile the nav is in-flow, so the hero should not be pushed down by a fixed-height offset. */
  body > nav.navbar + .project-hero {
    margin-top: 0;
  }

  .navbar-inner {
    flex-direction: column;
    justify-content: center;
    gap: 12px;
    height: auto;
  }

  .navbar-center-links,
  .nav-links {
    position: static;
    transform: none;
    flex-wrap: wrap;
    justify-content: center;
    height: auto;
  }
}