html {
  scroll-behavior: smooth;
}

/* Hero Section */
.gallery-hero {
  position: relative;
  background: url('../images/auto-expo-23/wheelkart-auto-expo-23.jpg') center/cover fixed no-repeat !important;
  color: #fff;
  text-align: center;
  min-height: 70vh; /* ensure a good height */
  display: flex;
  align-items: center; /* vertical centering */
  justify-content: center; /* horizontal centering */
  flex-direction: column;
  border-radius: 0 0 24px 24px;
  box-shadow: 0 8px 22px rgba(0,0,0,0.12);
  overflow: hidden;
  z-index: 1;
}

/* Dark overlay */
.gallery-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background: rgba(0, 30, 80, 0.65); /* dark blue */
  z-index: 0;
}

/* Text container */
.gallery-hero .hero-content {
  position: relative;
  z-index: 1;
  max-width: 800px;
  padding: 0 20px;
}




/* Back Button */
.gallery-hero .btn-back {
  display: inline-block;
  margin-bottom: 28px;
  padding: 10px 20px;
  color: #fff;
  font-size: 14px;
  font-weight: 600;
  text-decoration: none;
  border: 1.5px solid rgba(255,255,255,0.8);
  border-radius: 50px;
  background: rgba(255,255,255,0.1);
  backdrop-filter: blur(8px);
  transition: all 0.3s ease;
}
.gallery-hero .btn-back:hover {
  background: #fff;
  color: #0d6efd;
  border-color: #fff;
  transform: translateX(-4px);
}


/* Title */
.gallery-hero h1 {
  font-size: 44px;
  margin: 0 0 18px;
  font-weight: 800;
  line-height: 1.2;
}
.gallery-hero h1::after {
  content: "";
  display: block;
  margin: 14px auto 0;
  width: 80px;
  height: 4px;
  border-radius: 2px;
  background: #ffdd57; /* accent bar */
}
/* Responsive */
@media (max-width: 768px) {
  .gallery-hero {
    padding: 80px 15px 70px;
    background-attachment: scroll; /* avoid issues on mobile */
  }
  .gallery-hero h1 {
    font-size: 30px;
  }
  .gallery-hero p {
    font-size: 15px;
  }
}

/* Subtitle */
.gallery-hero p {
  font-size: 18px;
  opacity: 0.95;
  max-width: 720px;
  margin: 0 auto;
  line-height: 1.6;
}

/* Sticky Nav */
.gallery-nav {
  display: flex;
  justify-content: center;
  gap: 40px;
  padding: 14px 20px;
  background: #fff;
  border-bottom: 1px solid #eee;
  position: sticky;
  top: 0;
  z-index: 99;
}
.gallery-nav a {
  position: relative;
  text-decoration: none;
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  font-weight: 600;
  font-size: 14px;
  color: #000;
  padding: 10px 10px;
  transition: color 0.3s ease;
  cursor: pointer;
}
/* Red underline */
.gallery-nav a::after {
  content: '';
  position: absolute;
  bottom: 2px;
  left: 0;
  width: 0;
  height: 2px;
  background-color: #d50032;
  transition: width 0.3s ease;
}
.gallery-nav a:hover::after,
.gallery-nav a.active::after {
  width: 100%;
}
.gallery-nav a.active {
  color: #d50032;
}
.gallery-nav ul {
  display: flex;
  justify-content: center;
  gap: 20px;
  margin: 0;
  padding: 0;
  list-style: none;
}

/* Masonry Collage */
.masonry {
  column-count: 3;
  column-gap: 16px;
  padding: 40px 8%;
}
.masonry img {
  width: 100%;
  margin-bottom: 16px;
  border-radius: 12px;
  display: block;
  break-inside: avoid;
  box-shadow: 0 6px 16px rgba(0,0,0,0.08);
  cursor: pointer;
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}
.masonry img:hover {
  transform: scale(1.03);
  box-shadow: 0 10px 24px rgba(0,0,0,0.12);
}

/* Lightbox */
#lightbox {
  display: none;
  position: fixed;
  z-index: 1000;
  padding: 40px;
  inset: 0;
  width: 100%;
  height: 100%;
  background: rgba(0,0,0,0.9);
}
#lightbox img {
  margin: auto;
  display: block;
  max-width: 90%;
  max-height: 80%;
  border-radius: 10px;
}
#lightbox .close {
  position: absolute;
  top: 20px;
  right: 40px;
  color: #fff;
  font-size: 36px;
  font-weight: bold;
  cursor: pointer;
}

/* Responsive */
@media (max-width: 992px) {
  .masonry {
    column-count: 2;
    padding: 30px 5%;
  }
}
@media (max-width: 600px) {
  .gallery-hero {
    padding: 70px 15px 60px;
  }
  .gallery-hero h1 {
    font-size: 28px;
  }
  .gallery-hero p {
    font-size: 15px;
  }
  .masonry {
    column-count: 1;
    padding: 20px 5%;
  }
}