Вы не можете выровнять элементы, которые не имеют общего родителя, но что вы можете сделать, это нажать каждый «плюс» в нижней части каждой плитки.
Просто примените margin-top: auto;
к элементам «плюс».
Поскольку все плитки имеют одинаковую высоту, элементы «плюс» выстраиваются в ряд.
.tl {
width: 80%;
margin: auto;
display: flex;
color: #000;
margin-top: 70px;
justify-content: space-evenly;
padding-left: 18px;
/* padding-top: 30px; */
}
.tile {
text-align: left;
padding: 5px;
margin-top: 0px;
padding-top: 0px;
width: 100%;
padding-bottom: 20px;
display: flex;
flex-direction: column;
border: 1px solid green;
}
.plus {
align-self: flex-end;
padding: 1em;
background: red;
margin-top: auto;
}
<div class="tiles">
<div class="container tl">
<div class="tile chart">
<h3>SEO Optimized</h3>
<p>Lorem Ipsum is simply dummy text of the printing and typesetting industry. Lorem Ipsum has been the industry's standard dummy text ever since the 1500s, when an unknown printer took a galand scrambled it to make</p>
<a href="#" class="plus">+</a>
</div>
<div class="tile pad">
<h3>SEO Optimized</h3>
<p>Lorem ipsum dolor sit amet consectetur adipisicing elit. Ipsa animi ea commodi autem aspernatur dolores aliquam vel illo, voluptatum magni aperiam quibusdam blanditiis cum laboriosam earum, exercitationem rerum. Error, deleniti sequi quod repellendus
ducimus excepturi inventore aliquam impedit doloribus reprehenderit beatae obcaecati voluptates voluptas, ut fuga dignissimos culpa? Explicabo aperiam expedita nulla unde sed asperiores nostrum iure reiciendis qui aliquam id doloribus vel officiis
modi iusto mollitia, eum at, libero et dolore facilis suscipit dicta aspernatur corporis?</p><a href="#" class="plus">+</a>
</div>
<div class="tile cloud">
<h3>SEO Optimized</h3>
<p>Lorem Ipsum is simply dummy text of the printing and typesetting industry. Lorem Ipsum has been the industry's standard dummy text ever since the 1500s, when an unknown printer took a galley of type and scrambled it to make</p>
<a href="#" class="plus">+</a></div>
</div>