css selectors

HTML

<input type="text" />
<input readonly="readonly" type="text" />
<input read-only="readonly" type="text" />
<input read-only="read-only" type="text" />
<input read-only="read-only" type="text" />

CSS

input {
    float:left;
    clear:both;
    margin: 10px;
    background: #ff0;
}

input[readonly=readonly] {
    background: #333;
}

input[read-only=readonly] {
    background: #000000;
}

input[read-only=read-only] {
    background: #333;
}

input[read-only="read-only"] {
    background: #888;
}