input {
  display: block;
  margin-top: 5px;
  margin-bottom: 15px;
}

th, td {
  padding: 15px;
}

table, th, td {
  border: 1px solid black;
}

input {
  border: 2px solid currentcolor;
}

input:invalid {
  border: 2px dashed red;
}

input:invalid:focus {
  background-image: linear-gradient(magenta, pink);
}