.pdf-tabs {
  display: flex;
  gap: 12px;
  margin-bottom: 24px;
  flex-wrap: wrap;
}

.pdf-tab {
  padding: 12px 24px;
  border: 2px solid #e5e6eb;
  background: #fff;
  color: #4e5969;
  font-size: 15px;
  font-weight: 500;
  border-radius: 8px;
  cursor: pointer;
  transition: all 0.3s ease;
}

.pdf-tab:hover {
  border-color: #165DFF;
  color: #165DFF;
}

.pdf-tab.active {
  background: #165DFF;
  border-color: #165DFF;
  color: #fff;
}

.pdf-content {
  min-height: 400px;
}

.pdf-mode {
  animation: fadeIn 0.3s ease;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: translateY(0); }
}

.upload-zone {
  border: 2px dashed #c9cdd4;
  border-radius: 12px;
  padding: 60px 24px;
  text-align: center;
  cursor: pointer;
  transition: all 0.3s ease;
  background: #fafafa;
  margin-bottom: 20px;
  position: relative;
}

.upload-zone:hover {
  border-color: #165DFF;
  background: #f0f5ff;
}

.upload-zone.dragover {
  border-color: #165DFF;
  background: #e8f3ff;
}

.upload-text {
  font-size: 16px;
  color: #4e5969;
  font-weight: 500;
}

.file-list {
  margin-bottom: 20px;
  max-height: 300px;
  overflow-y: auto;
}

.file-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 12px 16px;
  background: #f7f8fa;
  border: 1px solid #e5e6eb;
  margin-bottom: 8px;
  border-radius: 6px;
}

.file-item-info {
  display: flex;
  align-items: center;
  gap: 12px;
  flex: 1;
}

.file-item-name {
  font-weight: 500;
  color: #1d2129;
}

.file-item-size {
  font-size: 13px;
  color: #86909c;
}

.file-item-remove {
  padding: 4px 12px;
  background: #fff2f0;
  color: #f53f3F;
  border: none;
  border-radius: 4px;
  cursor: pointer;
  font-size: 13px;
}

.file-item-remove:hover {
  background: #f53f3f;
  color: #fff;
}

.split-options,
.compress-options,
.toimage-options {
  display: flex;
  gap: 16px;
  align-items: center;
  margin-bottom: 20px;
  flex-wrap: wrap;
  padding: 16px;
  background: #f7f8fa;
  border-radius: 8px;
}

.split-options label,
.compress-options label,
.toimage-options label {
  font-size: 14px;
  font-weight: 500;
  color: #4e5969;
}

.split-options select,
.compress-options select,
.toimage-options select {
  padding: 8px 12px;
  border: 1px solid #c9cdd4;
  border-radius: 6px;
  font-size: 14px;
  cursor: pointer;
}

.split-options input[type="text"] {
  flex: 1;
  min-width: 200px;
  padding: 8px 12px;
  border: 1px solid #c9cdd4;
  border-radius: 6px;
  font-size: 14px;
}

.btn-lg {
  width: 100%;
  padding: 16px 32px;
  font-size: 16px;
  font-weight: 600;
  border-radius: 10px;
}

.result-area {
  margin-top: 24px;
  animation: fadeIn 0.3s ease;
}

#result-info {
  padding: 20px;
  line-height: 1.8;
  color: #4e5969;
}

.btn-tiny {
  padding: 6px 16px;
  font-size: 13px;
  border: 1px solid #c9cdd4;
  background: #fff;
  color: #4e5969;
  border-radius: 4px;
  cursor: pointer;
  transition: all 0.2s ease;
}

.btn-tiny:hover:not(:disabled) {
  border-color: #165DFF;
  color: #165DFF;
}

.btn-tiny:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

@media (max-width: 768px) {
  .pdf-tabs {
    gap: 8px;
  }
  
  .pdf-tab {
    padding: 10px 16px;
    font-size: 14px;
  }

  .upload-zone {
    padding: 40px 16px;
  }

  .split-options,
  .compress-options,
  .toimage-options {
    flex-direction: column;
    align-items: stretch;
  }
}