/* ============================================================
   Layout: nav, section shells, grids, responsive breakpoints
   ============================================================ */

.container {
  max-width: var(--container-max);
  margin: 0 auto;
  position: relative;
}

/* ---------- Fixed nav ---------- */
.site-nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 50;
  display: flex;
  align-items: center;
  gap: 28px;
  padding: 14px 36px;
  background: var(--nav-glass);
  -webkit-backdrop-filter: blur(10px);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid rgba(20, 20, 20, 0.12);
}

.nav-brand {
  display: flex;
  align-items: baseline;
  gap: 12px;
  color: var(--ink);
  min-width: 0;
}
.nav-wordmark { white-space: nowrap; }
.nav-brand img {
  width: 44px; height: 44px;
  object-fit: cover;
  border-radius: 50%;
  background: #fff;
  align-self: center;
}
.nav-wordmark {
  font-family: var(--font-display);
  font-size: 18px;
  letter-spacing: 0.06em;
}
.nav-at {
  font-family: var(--font-display);
  font-size: 13px;
  letter-spacing: 0.1em;
  color: var(--red);
  margin-left: -4px; /* tucked in close to the wordmark */
}

.nav-spacer { flex: 1; }

.nav-links {
  display: flex;
  align-items: center;
  gap: 26px;
  font-size: 14px;
  font-weight: 600;
  letter-spacing: 0.04em;
}
.nav-link { color: var(--ink); transition: color 0.18s ease; }
.nav-link:hover { color: var(--red); }

.nav-toggle {
  display: none;
  background: none;
  border: 2px solid var(--ink);
  width: 42px; height: 38px;
  padding: 0;
  cursor: pointer;
  position: relative;
}
.nav-toggle span {
  display: block;
  width: 20px; height: 2px;
  background: var(--ink);
  margin: 4px auto;
  transition: transform 0.25s ease, opacity 0.2s ease;
}
.nav-toggle[aria-expanded="true"] span:nth-child(1) { transform: translateY(6px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] span:nth-child(3) { transform: translateY(-6px) rotate(-45deg); }

.nav-panel { display: contents; }

/* ---------- Section shells ---------- */
.section {
  padding: var(--section-pad) var(--gutter);
  position: relative;
  overflow: hidden; /* contains gear watermarks */
}
.section--flush { overflow: visible; }

/* Two-column feature grid (mission, meetings intro).
   minmax(0,1fr) is load-bearing: bare 1fr lets photo slots blow the grid out. */
.grid-2 {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  gap: 60px;
  align-items: center;
}

/* Meeting cards / network logos */
.grid-cards { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 26px; }

/* Photo slot wrappers — min-width:0 + overflow guard (handoff gotcha) */
.photo-slot {
  min-width: 0;
  overflow: hidden;
  position: relative;
}
.photo-slot--420 { height: 420px; }
.photo-slot--400 { height: 400px; }

/* ---------- Responsive ---------- */
@media (max-width: 980px) {
  .nav-toggle { display: block; }
  .nav-panel {
    display: block;
    position: fixed;
    /* nav height: 14px padding x2 + 44px logo + 1px border */
    top: 73px; left: 0; right: 0;
    background: var(--bone);
    border-bottom: 1px solid var(--hairline-strong);
    padding: 10px 36px 24px;
    transform: translateY(-110%);
    /* visibility flips to hidden only AFTER the slide-away finishes,
       otherwise the close animation never paints */
    transition: transform 0.28s cubic-bezier(0.4, 0, 0.2, 1), visibility 0s linear 0.28s;
    visibility: hidden;
    z-index: 49;
  }
  .nav-panel.is-open {
    transform: translateY(0);
    visibility: visible;
    /* opening must show the panel immediately (no visibility delay) */
    transition: transform 0.28s cubic-bezier(0.4, 0, 0.2, 1), visibility 0s;
  }
  .nav-panel .nav-links {
    flex-direction: column;
    align-items: flex-start;
    gap: 0;
  }
  .nav-panel .nav-link {
    display: block;
    width: 100%;
    padding: 14px 0;
    border-bottom: 1px solid var(--hairline);
    font-size: 16px;
  }
}

@media (max-width: 900px) {
  :root { --section-pad: 72px; }
  .grid-2 { grid-template-columns: minmax(0, 1fr); gap: 40px; }
  .grid-cards { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .photo-slot--420, .photo-slot--400 { height: 320px; }
}

@media (max-width: 640px) {
  .grid-cards { grid-template-columns: minmax(0, 1fr); }
  .site-nav { padding: 12px 20px; gap: 16px; }
  /* nav height here: 12px padding x2 + 44px logo + 1px border */
  .nav-panel { padding: 6px 20px 18px; top: 69px; }
  .nav-wordmark { font-size: 15px; }
}

@media (max-width: 420px) {
  .nav-at { display: none; }
}