<!DOCTYPE html>
<html>
<head>
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<style>
* {
box-sizing: border-box;
}
body {
margin: 0;
font-family: Arial, Helvetica, sans-serif;
}
.header {
text-align: center;
padding: 32px;
}
.row {
display: -ms-flexbox;
display: flex;
-ms-flex-wrap: wrap;
flex-wrap: wrap;
padding: 0 4px;
}
.column {
-ms-flex: 50%;
flex: 50%;
padding: 0 4px;
}
.column img {
margin-top: 8px;
vertical-align: middle;
}
.btn {
border: none;
outline: none;
padding: 10px 16px;
background-color: #f1f1f1;
cursor: pointer;
font-size: 18px;