.pdf-merge-container {
  max-width: 600px;
  margin: 40px auto;
  padding: 30px;
  background: #1e1e1e;
  color: #f0f0f0;
  border-radius: 10px;
  box-shadow: 0 0 15px rgba(0,0,0,0.3);
  font-family: 'Montserrat', sans-serif;
}

.pdf-merge-container h1 {
  text-align: center;
  color: #605be5;
  font-family: 'Syne', sans-serif;
  font-weight: 700;
  margin-bottom: 10px;
}

.pdf-merge-container p {
  font-family: 'Montserrat', sans-serif;
  text-align: center;
  margin-bottom: 20px;
}

.pdf-merge-container input[type="file"] {
  width: 100%;
  margin-bottom: 20px;
  padding: 10px;
  background: #333;
  color: #fff;
  border: 1px solid #444;
  border-radius: 5px;
}

#fileList {
  list-style: none;
  padding: 0;
  margin: 20px 0;
}

#fileList li {
  background: #2c2c2c;
  margin: 5px 0;
  padding: 10px;
  border: 1px solid #555;
  border-radius: 5px;
  cursor: grab;
}

#mergeBtn {
  width: 100%;
  padding: 12px;
  background: #605be5;
  color: #fff;
  border: none;
  border-radius: 5px;
  font-family: 'Montserrat', sans-serif;
  font-weight: bold;
  cursor: pointer;
  margin-top: 10px;
}

#mergeBtn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}