Overwrite style.css styles from index.php style

Add this code in your theme’s functions.php

add_action('wp_footer', 'my_home_page_styles', PHP_INT_MAX);
function my_home_page_styles() {
    if(is_front_page()) {
    ?>
    <style>
        #main {
            margin-left: 0 !important;
        }
        .container {
            width: 95% !important;
        }
    </style>
    <?php
    }
}

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