$(document).ready(function () {
    var result = $('#result'),
        base = $('#base'),
        list = $('#list');
        
    $('#calc').on('click', function () {
        var baseVal = base.val(),
            px = list.val().split(','),
            html = [];
            
        $.each(px, function (i, v) {
            var px = parseInt(v),
                rem = parseFloat((px / parseInt(baseVal, 10)).toPrecision(4)),
                isBase = rem === 1 ? ' <i>(base)</i>' : '';
            html.push('<li>' + v + 'px = <span>' + rem + 'rem</span>' + isBase + '</li>');
        });
        
        result.html(html.join(''));
    }).click();
    
    $(document).on('click', '#result li', function () {
        var unit = $(this).find('span').text();
        prompt('Copy to clipboard: Ctrl+C, Enter', unit);
    });
});