How to change design for mobile (Bootstrap)

I am currently working on building a website. I have designed a basic pricing chart for the site (using bootstrap) The problem I am having, is when I resize my window, the design gets mis-aligned.

Here is the code for the current design so far

<div class="background-pricing container-fluid">
    <div class="container">
        <div class="row">
            <div class="payment-method">We accept:  Cash and Checks with payment due on Fridays of each week.</div>
        </div>
<!--infants and children -->
        <div class="row">
            <div class="infants-box col-sm-6 col-md-6 col-lg-6">
                <div class="infants">Infants</div>
            </div>
            <div class="col-sm-6 col-md-6 col-lg-6">
                <div class="children">Children 2+</div>
            </div>
        </div>

        <div class="row">
            <div class="full-time col-sm-6 col-md-6 col-lg-2">Full Time</div>
            <div class="prices-left-box col-sm-5 col-md-3 col-lg-5">
                <div class="prices-left">$200 Per Week</div>
            </div>
            <div class="prices-right-box col-sm-5 col-md-3 col-lg-5">
                <div class="prices-right">$150 Per Week</div>
            </div>
        </div>
        <div class="row">
            <div class="full-time col-sm-2 col-md-2 col-lg-2">Up to 4 Hours</div>
            <div class="prices-left-box col-sm-5 col-md-5 col-lg-5">
                <div class="prices-left">$125 Per Week</div>
            </div>
            <div class="prices-right-box col-sm-5 col-md-5 col-lg-5">
                <div class="prices-right">$100 Per Week</div>
            </div>
        </div>
    </div>
</div>

As you can see, in full screen, the chart is legible, but when resized, the chart is unreadable with the "infants" and "children 2+" side by side.

How would I make it easier to read?