/* ============================================================
   INSTITUTE HERO SLIDER
   Full-viewport photo spotlight. Navbar overlays transparently.
   Photos go in  assets/images/institute/1.jpg – 5.jpg
   ============================================================ */

/* ── Section shell ───────────────────────────────────────── */
.inst-hero {
  position: relative;
  width: 100%;
  height: 80vh;
  min-height: 400px;
  overflow: hidden;
  background: #06111f;       /* fallback while images load */
  z-index: 1;                /* sit above the fixed bg-mesh / bg-grid */
}

/* ── Slides ──────────────────────────────────────────────── */
.ih-slides {
  position: absolute;
  inset: 0;
}

.ih-slide {
  position: absolute;
  inset: 0;
  background-size: cover;
  background-position: center center;
  background-repeat: no-repeat;
  background-color: #06111f;   /* solid fallback — prevents bg-mesh bleed */
  opacity: 0;
  transform: scale(1.06);
  transition: opacity 1.1s ease, transform 7s ease;
  will-change: opacity, transform;
}

.ih-slide.ih-active {
  opacity: 1;
  transform: scale(1);        /* Ken Burns: zoom to natural size */
}

/* Placeholder gradient when image is missing or not yet added */
.ih-slide.ih-no-img {
  background-image: none !important;
  background: linear-gradient(135deg, #040e28 0%, #0a1e44 55%, #081060 100%);
  opacity: 1;
  transform: none;
}

/* ── Top gradient — keeps navbar text readable over any image ── */
.inst-hero::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 140px;
  background: linear-gradient(
    to bottom,
    rgba(4, 10, 28, 0.72) 0%,
    rgba(4, 10, 28, 0.30) 60%,
    transparent 100%
  );
  z-index: 3;
  pointer-events: none;
}

/* ── Bottom gradient — creates depth, shows bottom bar clearly ── */
.ih-overlay-bottom {
  position: absolute;
  bottom: 0; left: 0; right: 0;
  height: 45%;
  background: linear-gradient(
    to top,
    rgba(4, 10, 28, 0.90) 0%,
    rgba(4, 10, 28, 0.55) 40%,
    transparent 100%
  );
  z-index: 2;
  pointer-events: none;
}

/* ── Bottom bar ──────────────────────────────────────────── */
.ih-bottom-bar {
  position: absolute;
  bottom: 32px;
  left: 40px;
  right: 40px;
  z-index: 4;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

/* ── Label (bottom-left) ─────────────────────────────────── */
.ih-label-wrap {
  display: flex;
  align-items: center;
  gap: 10px;
  background: rgba(0, 0, 0, 0.50);
  border: 1px solid rgba(255, 255, 255, 0.14);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  padding: 10px 18px;
  border-radius: 100px;
}

.ih-live-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: #00e5ff;
  box-shadow: 0 0 8px rgba(0, 229, 255, 0.8);
  flex-shrink: 0;
  animation: ihPulse 2s ease-in-out infinite;
}

@keyframes ihPulse {
  0%, 100% { opacity: 1; box-shadow: 0 0 8px rgba(0,229,255,0.8); }
  50%       { opacity: 0.5; box-shadow: 0 0 3px rgba(0,229,255,0.3); }
}

.ih-label-text {
  font-size: 0.82rem;
  font-weight: 600;
  color: rgba(255, 255, 255, 0.90);
  letter-spacing: 0.04em;
  white-space: nowrap;
}

/* ── Dots (centre) ───────────────────────────────────────── */
.ih-dots {
  display: flex;
  align-items: center;
  gap: 8px;
}

.ih-dot-btn {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.35);
  border: none;
  cursor: pointer;
  padding: 0;
  transition: background 0.3s, width 0.3s, border-radius 0.3s;
}

.ih-dot-btn.ih-dot-active {
  background: #fff;
  width: 24px;
  border-radius: 4px;
}

/* ── Combined arrow pill (bottom-right) ──────────────────── */
.ih-arrow-pill {
  display: flex;
  align-items: center;
  background: rgba(255, 255, 255, 0.92);
  border-radius: 100px;
  overflow: hidden;
  box-shadow: 0 4px 24px rgba(0, 0, 0, 0.35);
}

.ih-arrow-pill button {
  background: none;
  border: none;
  cursor: pointer;
  color: #06111f;
  font-size: 1.25rem;
  font-weight: 700;
  width: 52px;
  height: 52px;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background 0.2s;
  line-height: 1;
}

.ih-arrow-pill button:hover {
  background: rgba(0, 0, 0, 0.08);
}

.ih-pill-divider {
  width: 1px;
  height: 24px;
  background: rgba(0, 0, 0, 0.15);
  flex-shrink: 0;
}

/* ── Progress bar ────────────────────────────────────────── */
.ih-progress {
  position: absolute;
  bottom: 0;
  left: 0;
  height: 3px;
  width: 0%;
  background: linear-gradient(90deg, #00e5ff, #0070f3);
  z-index: 5;
  box-shadow: 0 0 10px rgba(0, 229, 255, 0.5);
  transition: width linear;
}

/* ── Navbar: transparent + readable when over the slider ────── */
nav.main-nav.ih-at-top {
  background: transparent;
  backdrop-filter: none;
  -webkit-backdrop-filter: none;
  border-bottom-color: transparent;
  box-shadow: none;
}

/* Force all nav text white + text-shadow so it reads on any photo */
nav.main-nav.ih-at-top .nav-link-item,
nav.main-nav.ih-at-top .nav-logo {
  color: #ffffff;
  text-shadow: 0 1px 8px rgba(0, 0, 0, 0.75);
}

nav.main-nav.ih-at-top .nav-logo .accent {
  text-shadow: 0 1px 8px rgba(0, 0, 0, 0.75);
}

nav.main-nav.ih-at-top .nav-link-item:hover {
  color: var(--cyan, #00e5ff);
  text-shadow: 0 0 12px rgba(0, 229, 255, 0.6);
}

/* ── Reduced motion ──────────────────────────────────────── */
@media (prefers-reduced-motion: reduce) {
  .ih-slide { transition: opacity 0.8s ease; transform: none !important; }
}

/* ── Mobile ──────────────────────────────────────────────── */
@media (max-width: 768px) {
  /*
   * Use vw-based height instead of vh so the container stays
   * landscape-proportioned on portrait phones.
   * 56vw ≈ 16:9 ratio — landscape group photos fill edge-to-edge
   * with no side-cropping. max() keeps a decent minimum on tiny screens.
   */
  .inst-hero {
    height: max(56vw, 220px);
    min-height: unset;
  }

  .ih-bottom-bar {
    bottom: 14px;
    left: 12px;
    right: 12px;
    flex-wrap: wrap;
    gap: 8px;
  }

  .ih-label-wrap { padding: 7px 12px; }
  .ih-label-text { font-size: 0.72rem; }

  .ih-dots { order: 3; width: 100%; justify-content: center; margin-top: 2px; }

  .ih-arrow-pill button { width: 40px; height: 40px; font-size: 1.05rem; }
}

@media (max-width: 480px) {
  .ih-label-wrap { display: none; }
}