/* Styles for the popup window and overlay */ .popup { display: none; /* Hidden by default */ position: fixed; z-index: 1; left: 0; top: 0; width: 100%; height: 100%; overflow: auto; background-color: rgb(0,0,0); background-color: rgba(0,0,0,0.4); padding-top: 15%; } .popup-content { background-color: #fefefe; margin: 5% auto; padding: 20px; border: 1px solid #888; width: 80%; max-width: 600px; } .close-btn { color: #aaa; float: right; font-size: 28px; font-weight: bold; } .close-btn:hover, .close-btn:focus { color: black; text-decoration: none; cursor: pointer; } Insulation is 40 gsm thermal poly fill in front hybrid panel Water-repellent Center front reverse coil zipper with faux leather toggles Lower-zippered pockets Contrast striping detail at zippers 100% recycled nylon overlay polyester/rayon/spandex weft knit Size Chart × HOW TO MEASURE WIDTH Measure the shirt from armpit to armpit on a flat surface. Men's Medium Large XL XXL XXXL Width (in) 22.25 23.75 25.75 27.25 29.25 Length (in) 28 29 30 31 32 Sleeve (in) 34.5 35.5 36.5 37.5 38.5 // Get the popup var popup = document.getElementById("popup"); // Get the button that opens the popup var btn = document.getElementById("popupBtn"); // Get the element that closes the popup var span = document.getElementsByClassName("close-btn")[0]; // When the user clicks the button, open the popup btn.onclick = function() { popup.style.display = "block"; } // When the user clicks on (x), close the popup span.onclick = function() { popup.style.display = "none"; } // When the user clicks anywhere outside of the popup, close it window.onclick = function(event) { if (event.target == popup) { popup.style.display = "none"; } }