Trouble with making my website responsive - html

Question

I am currently attempting to make my website responsive i.e. images scale up and down with page resizing, content stacks above each other, etc. I was under the impression that I had taken the appropriate steps, but the elements are still stretching in size when resizing and the contents are not staying in their original positions.
How can I achieve this result while keeping all of my elements intact?
* {
margin: 0;
padding: 0;
box-sizing: border-box;
}
body {
background-image: url(img/food-background.jpg);
background-attachment: fixed;
height: 100%;
}
.main-content {
display: flex;
flex-wrap: wrap;
}
.container {
margin-left: auto;
margin-right: auto;
width: 1140px;
}
.Navbar {
text-align: center;
display: block;
margin-top: 2%;
}
#center-logo {
width: 100%;
max-width: 200px;
height: auto;
text-align: center;
}
#Navbar_Link-Toggle {
display: none;
}
img {
width: 40%;
}
.links {
text-decoration: none;
font-size: 13px;
color: black;
font-weight: bold;
padding: 25px;
}
.links:hover {
color: #f58300
}
a:visited {
color: black;
}
.header {
width: 100%;
display: flex;
justify-content: center;
align-items: center;
margin-top: 3%;
height: auto;
background-color: yellow;
}
#food {
height: 65vh;
width: 100%
}
.footer {
margin-top: 100%;
bottom: 0;
width: 100%;
text-align: center;
font-size: 10px;
margin-left: auto;
margin-right: auto;
background-color: #f7f7f7;
}
.top {
float: left;
width: 100%;
}
#olive-green {
margin-top: 5%;
position: absolute;
right: 50px;
max-width: 450px;
}
#coral {
max-width: 450px;
position: absolute;
left: 50px;
margin-top: 5%;
}
#teal {
max-width: 450px;
position: absolute;
left: 50px;
margin-top: 50%;
}
#honey {
margin-top: 50%;
position: absolute;
right: 50px;
max-width: 450px;
}
.images {
content: "";
clear: both;
display: table;
}
#media screen and (max-width: 900px) {
.top {
width: 100%;
}
.bottom {
width: 100%;
}
}
<div class='main-content'></div>
<div id='Navbar_Link-Toggle' style='font-size: 20px'>
<i id='main' class='fas fa-bars'></i>
</div>
<div class='container'>
<div class='Navbar'>
<a class='links' href=''>FOOD</a>
<a class='links' href=''>FUN</a>
<img id='center-logo' src='img/SAMO.png'>
<a class='links' href=''>HISTORY</a>
<a class='links' href=''>LOCATION</a>
</div>
</div>
<div class='header'>
<img id='food' src='img/food.jpg'>
</div>
<div class='images'>
<div class='top'>
<img id='coral' src='img/coral.png'>
<img id='olive-green' src='img/olive-green.jpg'>
</div>
<div class='middle'>
<img id='teal' src='img/teal.jpg'>
<img id='honey' src='img/honey.jpg'>
</div>
</div>
</div>
<div class='footer'>
<p>200 Santa Monica Pier, Suite A Santa Monica, CA 90401</p><br>
<p>Questions? Drop us a message at: info#santamonicapier.org or 310-458-8900</p><br>
<p>All Rights Reserved © 2019 Santa Monica Pier</p>
</div>

Answer 1

You have an extra closing div on the first line of your HTML. So your .main-content element is actually being closed right away instead of wrapping around the rest of the elements.