<style>
html, body {
margin: 0;
padding: 0;
}
.main {
max-width: 400px;
width: 100%;
max-height: 360px;
margin: 0 auto;
}
.block, .block2 {
display: flex;
justify-content: start;
align-items: flex-end;
width: 100%;
border: 2px solid red;
box-sizing: border-box;
padding-bottom: 100%;
}
.block {
margin-bottom: 10px;
}
span {
display: inline-block;
width: 100%;
}
</style>
</head>
<body>
<div class="main">
<div class="block">
<!--<div><span>ПРИВЕТ</span></div>-->
</div>
<div class="block2">
<!--<div><span>ПРИВЕТ</span></div>-->
</div>
</div>