<style>input[type=checkbox] { background-color: #F00; color: #0F0; } </style>
<input type="checkbox" CHECKED>
This is not a cross-browser solution (hey, IE!). Here is more portable:
<style> input.checkbox { background-color: #F00; color: #0F0; } </style>
<input type="checkbox" class="checkbox" CHECKED>
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