/* =========================================================
 🧭 ACTIVITY DETAIL PAGE
========================================================= */

/* 🔹 โครงหลัก */
.activity-detail {
  max-width: 1000px;
  margin: 40px auto;
  padding: 20px;
  background: #fff;
  border-radius: 12px;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
}

/* 📸 Cover Image */
.activity-cover img {
  width: 100%;
  max-height: 400px;
  object-fit: cover;
  border-radius: 10px;
  margin-bottom: 20px;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.2);
}

/* 🏷️ Title */
.activity-title {
  font-size: 28px;
  color: #003399;
  font-weight: bold;
  margin-bottom: 15px;
  text-align: center;
}

/* 📝 Description */
.activity-description p {
  font-size: 16px;
  line-height: 1.6;
  color: #555;
  margin-bottom: 12px;
  text-align: justify;
}

/* 🖼️ Gallery */
.activity-gallery {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: 15px;
  margin: 25px 0;
}

.activity-gallery img {
  width: 100%;
  height: 180px;
  object-fit: cover;
  border-radius: 8px;
  cursor: pointer;
  transition: transform 0.25s ease, box-shadow 0.25s ease;
}

.activity-gallery img:hover {
  transform: scale(1.05);
  box-shadow: 0 4px 10px rgba(0, 0, 0, 0.25);
}

/* 🗂️ Meta Info */
.activity-meta {
  margin-top: 20px;
  font-size: 15px;
  color: #444;
  border-top: 1px solid #eee;
  padding-top: 15px;
}

.activity-meta p {
  margin: 5px 0;
}

/* 🔙 Back Button */
.btn-back {
  display: inline-block;
  margin-top: 25px;
  padding: 10px 20px;
  background: #003399;
  color: #fff;
  text-decoration: none;
  border-radius: 6px;
  transition: background 0.3s ease;
}

.btn-back:hover {
  background: #001f7a;
}

/* =========================================================
 📸 Lightbox Popup
========================================================= */

.lightbox {
  display: none;
  position: fixed;
  z-index: 9999;
  left: 0;
  top: 0;
  width: 100%;
  height: 100%;
  background-color: rgba(0, 0, 0, 0.8);
  justify-content: center;
  align-items: center;
}

.lightbox img.lightbox-content {
  max-width: 90%;
  max-height: 85%;
  border-radius: 10px;
  box-shadow: 0 0 15px rgba(255, 255, 255, 0.5);
}

.lightbox .close {
  position: absolute;
  top: 20px;
  right: 30px;
  color: #fff;
  font-size: 40px;
  font-weight: bold;
  cursor: pointer;
  transition: 0.3s;
}

.lightbox .close:hover {
  color: #ff5555;
}

/* =========================================================
 📱 Responsive Design
========================================================= */

@media (max-width: 900px) {
  .activity-title { font-size: 24px; }
  .activity-gallery {
    grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
  }
  .activity-gallery img { height: 160px; }
}

@media (max-width: 600px) {
  .activity-detail { padding: 15px; }
  .activity-title { font-size: 20px; }
  .activity-gallery {
    grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
    gap: 8px;
  }
  .activity-gallery img { height: 140px; }
  .activity-description p { font-size: 14px; }
}