<li>
    <a href="#" class="custom">
        <input type="checkbox" name="cb1" id="cb1" />
        <label for="cb1">checkbox 1</label>
    </a>
    <a href="#"></a>
</li>

.custom {
     padding: 0;
}

.custom > div {
    margin: 0;
}

.custom > div > label {
    border-radius: 0;
    border: 0;
}