I am building a wordpress theme on a localhost, using phpmyadmin and Ampps.
I have pasted the following into the style.css folder
    body {
    font-family: Arial;
    font-size: 15px;
    color:  #333333
    background: #f4f4f4;
    margin:0;
    padding:0;
    line-height: 1.7em;
}
header {
    background: #393939;
    color: #ffffff;
    padding: 20px 10px;
}
header h1 {
    color: #ffffff;
    margin:0;
    padding:0;
    padding-bottom: 10px;
}
a {
    color: #333333;
}
article.post {
    border-bottom: 1px #cccccc solid;
    overflow: hidden;
    padding-bottom: 20px;
}
.container {
    width:1020px;
    margin:0 auto;
    overflow: auto;
}
.main {
        margin: 15px 0;
}
footer {
    background: #393939;
    color: #ffffff;
    padding: 20px 10px;
    text-align: center;
}
article.post a.button {
    display: inline-block;
    background:#333333;
    color:white;
    padding: 10px 5px;
    margin-bottom:  10px;
    text-decoration: none;
}
.meta {
    background:#333333;
    color:white;
    padding: 5px;
}
.post-thumbnail img{
    width: 100%;
    height:auto;
.main-nav li{
    list-style: none;
    float: left;
    padding-right: 15px;
}
.main-nav {
    background: #4169E1;
    color: #ffffff;
}
The code in my header.php folder is this:
<nav class="main-nav">
        <div class="container">
            <?php 
                $args = array(
                'theme_location'    => 'primary'
            );
            ?>
            <?php wp_nav_menu($args); ?>
        </div>
    </nav>
And then the functions.php code is this:
function simple_theme_setup() {
        //Featured Image Support
        add_theme_support('post-thumbnails');
        //Menus
        register_nav_menus(array(
            'primary'   => __('Primary Menu')
        ));
    }
I'm expecting to see the changes immediately on the site, as it has before, but this isn't occurring.
I go to "view page source" and click on the style.css link. it takes me there but the changes to the style sheet are not present.
I retried a couple of minutes later, and the changes to the stylesheet are present, but the changes have not taken effect on the site.
I read that I may need to clear cache files so I cleared my browsing cache but that didn't do anything . Would anyone have any input on this?
EDIT: after some more digging, I'm getting the feeling it's some other style that's  overriding it that was declared earlier (based on this answer). I put the !important tags on the main-nav styles but that still didn't return anything.
