$(document).ready(function() {
    var children = $("#gsm").children();
    var count = children.length;
    var size = 0;
    for(var i=count; i>0; i--) {
        size += parseInt(children.eq(i-1).css("width").slice(0, -2));
        if(size > 510) {
            break;
        }
    }
    for(var k=0; k<i; k++) {
        children.eq(k).hide();
    }
});