/* Background Full Page */
body {
  margin: 0;
  font-family: Arial, sans-serif;
  background: url("deloitte3.jpeg") no-repeat center center/cover;
  min-height: 100vh;
  overflow-x: hidden;
}

/* Dark Overlay */
.overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.75);
  z-index: -1;
}

/* Header */
.gallery-header {
  text-align: center;
  padding: 50px 20px;
  color: white;
}

.gallery-header h1 {
  font-size: 50px;
  color: cyan;
  text-shadow: 0 0 20px rgba(0, 255, 255, 0.6);
}

.gallery-header p {
  font-size: 18px;
  opacity: 0.8;
}

/* Back Button */
.back-btn {
  display: inline-block;
  margin-top: 20px;
  padding: 10px 25px;
  border-radius: 25px;
  text-decoration: none;
  background: cyan;
  color: black;
  font-weight: bold;
  transition: 0.3s;
}

.back-btn:hover {
  transform: scale(1.1);
}

/* Gallery Grid */
.gallery-container {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 25px;
  padding: 40px;
}

/* Card */
.gallery-card {
  border-radius: 18px;
  overflow: hidden;
  cursor: pointer;
  box-shadow: 0 0 20px rgba(0, 255, 255, 0.15);
  transition: 0.4s ease;
}

.gallery-card img {
  width: 100%;
  height: 260px;
  object-fit: cover;
  transition: 0.4s ease;
}

/* Hover Effect */
.gallery-card:hover {
  transform: scale(1.05);
  box-shadow: 0 0 35px rgba(0, 255, 255, 0.5);
}

.gallery-card:hover img {
  transform: scale(1.15);
}

/* Popup Preview */
.popup-img {
  position: fixed;
  top: 0;
  left: 0;
  background: rgba(0, 0, 0, 0.9);
  height: 100%;
  width: 100%;
  display: none;
  justify-content: center;
  align-items: center;
  z-index: 999;
}

.popup-img img {
  max-width: 85%;
  max-height: 80%;
  border-radius: 20px;
  box-shadow: 0 0 30px cyan;
}

.popup-img span {
  position: absolute;
  top: 30px;
  right: 50px;
  font-size: 50px;
  color: white;
  cursor: pointer;
}