* {
  box-sizing: border-box;
  font-family: system-ui, sans-serif;
}

body {
  margin: 0;
  background: #f4f6f8;
}

.container {
  max-width: 600px;
  margin: auto;
  padding: 1rem;
}

h1 {
  text-align: center;
}

#drop-zone {
  border: 2px dashed #888;
  padding: 2rem;
  text-align: center;
  border-radius: 12px;
  background: #fff;
  margin-bottom: 1rem;
}

#drop-zone.dragover {
  border-color: #007bff;
  background: #eef5ff;
}

.upload-btn {
  display: inline-block;
  padding: 0.5rem 1rem;
  background: #007bff;
  color: white;
  border-radius: 6px;
  cursor: pointer;
}

.controls {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 1rem;
}

button {
  padding: 0.6rem 1.2rem;
  border: none;
  border-radius: 6px;
  background: #28a745;
  color: white;
  cursor: pointer;
}

button:disabled {
  background: #aaa;
}

#fileList {
  list-style: none;
  padding: 0;
}

#fileList li {
  background: white;
  padding: 0.5rem;
  margin-bottom: 0.4rem;
  border-radius: 6px;
  font-size: 0.9rem;
}

#previewGrid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(120px, 1fr));
  gap: 0.75rem;
}

.image-card {
  background: white;
  border-radius: 10px;
  padding: 0.4rem;
  text-align: center;
  cursor: grab;
}

.image-card.dragging {
  opacity: 0.5;
}

.image-card img {
  width: 100%;
  height: 90px;
  object-fit: cover;
  border-radius: 8px;
}

.image-card button {
  margin-top: 0.3rem;
  width: 100%;
  background: #dc3545;
  font-size: 0.8rem;
}