Create A Snippet for Sidebar

See video on what it looks like but follow instructions below on how to implement the code.

1. First, we have to add a Sidebar menu in the Navigation
Go to Online Store >Navigation> Click Add menu.
2. Make sure you write title "Sidebar Menu"
3. Link collections you want to show
4. Click "save menu"
5. Then, we need to go to Online store> Themes> Actions> Edit code>
6. Go to Snippets folder, create a new snippet and name it custom-sidenav. Replace the code below, then click SAVE

<style>
.sidenav {
height: 90%;
width: 0;
position: fixed;
z-index: 5;
top: 100;
left: 10;
background-color: {{ background_color }};
overflow-x: hidden;
transition: 0.3s;
padding-top: 10px;
}

.sidenav a {
padding: 8px 8px 8px 15px;
text-decoration: none;
font-size: 20px;
color: {{ font_color}};
line-height: 20px;
display: block;
transition: 0.3s;
}

.sidenavTitle {
color: {{ title_font_color }};
font-size: 20px;
}
.sidenav a:hover {
color: {{ title_hover_color }};
}
/* Dancing Title */
.dancing {
height: 10%;
width: 50%;
font-size:20px;
color: {{ dancing_title_color }};
border: 0;
padding: 10px 20px;
position: relative;
padding-left: 40px;
word-wrap: break-word;
animation-name: shake;
animation-duration: 1s;
animation-iteration-count: infinite;
animation-timing-function: ease-in;
cursor:pointer;
}

.dancing :hover {
color: {{ dancing_title_hoover_color }};
animation-duration: 5s;

}

@keyframes shake {
0% { transform: translate(2px, 2px) rotate(0deg); }
10% { transform: translate(-2px, -3px) rotate(-3deg); }
20% { transform: translate(-4px, 1px) rotate(3deg); }
30% { transform: translate(4px, 3px) rotate(2deg); }
40% { transform: translate(2px, -5px) rotate(3deg); }
50% { transform: translate(-2px, 3px) rotate(-3deg); }
60% { transform: translate(-4px, 2px) rotate(0deg); }
70% { transform: translate(4px, 2px) rotate(-3deg); }
80% { transform: translate(-2px, -5px) rotate(3deg); }
90% { transform: translate(2px, 3px) rotate(0deg); }
100% { transform: translate(4px, -2px) rotate(-3deg); }
}

.dropdown-btn {
text-decoration: none;
font-size: 30px;
color: {{ dropdown_color }};
border: none;
background: none;
cursor: pointer;
outline: none;
margin-left: 0;
padding: 0;
margin-right: 25px;
}

.dropdown-container {
display: none;
padding-left: 30px;
}

@media screen and (max-height: 450px) {
.sidenavTitle {
font-size: 10px; };
.sidenav {padding-top: 10px;
padding-left: 10px;
z-index: 9999;}
.sidenav a {font-size: 20px;
z-index: 9999;}
}

</style>

<div id="mySidenav" class="sidenav" onmouseleave="closeNav()" onclick="closeNavClick()">
<div class="grid grid__item small-up--two-thirds" >
<h3 class="sidenavTitle text-center" > {{ sidenav_title }} </h3>

{% assign sidebar_link = linklists.sidebar-menu.links %}
<ul> {% for sidebar in sidebar_link %}
<li> <a href="{{ sidebar.url }}">{{ sidebar.title }}</a>
<button class="dropdown-btn">
{% assign child_list_handle = sidebar.title | handleize %}
{% assign child_list = linklists[child_list_handle] %}
{% for child_link in child_list.links %}
{% if child_list != blank %}
<strong>+</strong>
</button>
<ul class="dropdown-container">
<li><a href="{{ child_link.url }}">{{ child_link.title }}</a></li>
</ul>
</li>
{% endif %}
{% endfor %}
{% endfor %}
</ul>

</div>
</div>

<div class= "dancing">
<span onclick="openNav()">
<h3>{{ dancing_title }}</h3>
</span>
</div>

<script>
function openNav() {
document.getElementById("mySidenav").style.width = "250px";
document.body.style.backgroundColor = 'rgba(0,0,0,0)';
}

function closeNav() {
document.getElementById("mySidenav").style.width = "0";
}

document.addEventListener('mousedown',function(event){
var side_dom = document.getElementById("mySidenav")
if(side_dom.style.width == '250px'){
if(!side_dom.contains(event.target)){
document.getElementById("mySidenav").style.width = "0";
}
}
})

var dropdown = document.getElementsByClassName("dropdown-btn");
var i;
for (i = 0; i < dropdown.length; i++) {
dropdown[i].addEventListener("click", function() {
this.classList.toggle("active");

var dropdownContent = this.nextElementSibling;
if (dropdownContent.style.display === "block") {
dropdownContent.style.display = "none";
this.innerHTML = "<strong>+</strong>";
} else {
dropdownContent.style.display = "block";
this.innerHTML = "<strong>-</strong>";

}
});
}
</script>

7. Replace the code in green to real value. 
8. Go to Section folder and open header.liquid. Before </header>, place the code below, then click SAVE
{% render 'custom-sidenav' %}