.product_list > ul {
    list-style: none outside none;
    padding: 0;
    margin: 0;   
    overflow: hidden;
}
.product_list li {
    float: left;  
}

.category_list > ul {
    list-style: none outside none;
    padding: 0;
    margin: 0;   
    overflow: hidden;
}
.category_list li {
    float: left;  
}