input {
    border: none;
    border-bottom: solid 2px blue;
}

input.wordle {
    width: 1.1em;
    height: 1.1em;
    text-align: center;
    border: solid 3px gray;
    text-transform: uppercase;
    font-size: xxx-large;
    font-weight: bold;
    border-radius: 5px;
    color: transparent;
    text-shadow: 0 0 0 black;
}

input.wordle:focus {
    color: transparent;
    text-shadow: 0 0 0 black;
    outline: transparent;
    border: solid 6px lightgrey;
}

input:disabled {
  background: #eee;
}