Making checkbox transparent [duplicate]

This question already has an answer here:

• How to style checkbox using CSS? 19 answers

I've made a form with a checkbox. Now I need to make a checkbox appear as on the image:

What would be the best way to achieve this?

Also, they checkbox should be :checked once the label is clicked.

HTML:

<label>
    <input id="custom-checkbox" type="checkbox" required>
    Disclaimer: Click here if you are okay...
</label>