body {
  font-family: Arial, sans-serif;
  margin: 20px;
}

button {
  margin: 5px;
  padding: 8px 12px;
}

select {
  margin: 5px;
  padding: 5px;
}

#categoryDiv {
  margin-top: 10px;
  display: none;
}

table {
  border-collapse: collapse;
  margin-top: 20px;
  width: 100%;
  display: none;
}

th, td {
  border: 1px solid #ccc;
  padding: 8px;
  text-align: left;
}

th {
  background: #f4f4f4;
}

a:link,
a:visited {
  color: blue;      
}