Vertical Alignment - html

Question

I am trying to align my "cards" vertically when viewed from a mobile phone however I cannot seem to get the syntax right. I tried to 'text-align: center;' float:none' among other tries but I can't seem to figure it out. Any help will be appreciated. thank you.
/* Extra small devices (portrait phones, less than 576px) */
#media (max-width: 575px) {
.card {
display: block;
float: none;
width: 100%;
text-align: center;
}
}
<div class="card">
<img src="img/websume.png" height="240" width="356" alt="Card image cap">
<p class="card-text">My "Web-sume" was my first site to include Bootstrap 4. The site is a responsive site, with a feature only available to moblie devises. The site consist of mostly Bootstrap custom layouts.</p>
</div>
<div class="card">
<img src="img/websume_drpdwn.png" height="240" width="356" alt="Card image cap">
<p class="card-text">The "Web-sume" has several fixed images as well as a drop down section which includes my address as well as social links. I used the -web kit layouts for the 'Experience' section of the site.</p>
</div>
<div class="card">
<img src="img/websume_exp.png" height="240" width="356" alt="Card image cap">
<p class="card-text">As mentioned before, the site, when viewed through a mobile devise has a feature where if a client wants to get in contact with me they do not have to scroll all the way to the bottom of the page to get my contact information, a 'email' and 'phone' button appears for easy access.</p>
</div>

Answer 1

Just a simple oversight - it's the CSS comment breaking your #media query. You used // Extra small devices (portrait phones, less than 576px) initially, and in CSS, the comment syntax is /* Extra small devices (portrait phones, less than 576px) */

Answer 2

If I understand the problem correctly, your cards are going off the edge of the screen. This is due to the fact that while you're setting the width of .card to 100% for mobiles, you're hard-coding in the widths of the images, and not actually forcing the images to be contained within the bounds of their respective .card containers.
The best way to correct this is to specify a max width for all images:
img {
max-width: 100%;
}
Note that you'll probably also want to set height: auto, to make sure that the images don't get squashed:
#media (max-width: 575px) {
img {
height: auto;
}
}
I've created a fiddle showcasing this here.
Hope this helps! :)