.project-section {
  padding: 40px 20px;
  text-align: center;
}

.project-section h2 {
  color: #c00;
  margin-bottom: 30px;
font-weight: bold;
}

.project-section h3 {
    font-size: 22px;
    font-weight: 500;
    color: #01bf25;
}

.project-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.project-item {
  position: relative;
  overflow: hidden;
  border-radius: 12px;
  cursor: pointer;
}

.project-item img {
  width: 100%;
  object-fit: cover;
  transition: 0.4s;
}

/* hover zoom nhẹ */
.project-item:hover img {
  transform: scale(1.05);
}

/* overlay */
.overlay {
  position: absolute;
  bottom: -100%;
  left: 0;
  width: 100%;
  padding: 15px;
  background: rgba(0,0,0,0.7);
  color: #fff;
  text-align: center;
  transition: 0.4s;
}

.project-item:hover .overlay {
  bottom: 0;
}

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

.lightbox img {
  max-width: 90%;
  max-height: 80%;
  border-radius: 10px;
}

/* close */
.close {
  position: absolute;
  top: 20px;
  right: 30px;
  font-size: 35px;
  color: #fff;
  cursor: pointer;
}

/* next prev */
.nav {
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  font-size: 40px;
  color: #fff;
  cursor: pointer;
  padding: 10px;
}

.prev { left: 20px; }
.next { right: 20px; }

/* responsive */
@media (max-width: 768px) {
  .project-grid {
    grid-template-columns: repeat(1, 1fr);
  }

  .project-item img {
    height: 180px;
  }
  .project-section h3 {
    font-size: 17px;
    font-weight: 500;
    color: #01bf25;
    }

}