Hey kishan_vachhani111,

Please provide the page URL so we can write up what's possible.

Thanks 

Hey Again,

I am afraid this cant be adjusted with CSS alone. 

Try adding the JS code in the Salient Theme Options Panel and check:

jQuery(document).ready(function() {
    // Initialize the twentytwenty plugin
    jQuery('.twentytwenty-container').twentytwenty();

    // Reset the handle position to 20% after initialization
    setTimeout(function() {
        jQuery('.twentytwenty-handle').css('left', '20%');
        jQuery('.twentytwenty-before').css('clip', 'rect(0, ' + (jQuery('.twentytwenty-container').width() * 0.2) + 'px, 9999px, 0)');
    }, 100);
});

Thanks