Todo styles

.css

body {
  font-family: Arial, sans-serif;
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

input[type='text'] {
  padding: 5px;
}

button {
  padding: 5px 10px;
  margin-left: 5px;
  cursor: pointer;
}

ul {
  list-style: none;
  padding: 0;
}

button {
  padding: 5px 10px;
  margin-left: 5px;
  cursor: pointer;
  border: 1px solid #ccc;
  background-color: #f9f9f9;
}

button:hover {
  background-color: #e0e0e0;
}

button:focus {
  outline: none;
  border-color: #000;
}

button.active {
  font-weight: bold;
  border-color: #000;
}