(Squarespace) Custom Fullscreen Burger Menu

Today I will guide you how to create a fullscreen burger menu on desktop (7.1 version). See demo in below screenshot
fullscreen-burger1-min
https://tuanphan.squarespace.com/burger-menu-2?noredirect
pass: abc
(here not include image change on hover text effect, if you need this effect just share your site url, I can tweak code for your case)

#1. First you need to add 2 Sections in Footer. Suppose section 3 and 4
then design your layout



You can design whatever you want, here is just a random design for me to write.

#2. Next, change Header Layout to this

#3. Use this code to Design > Custom CSS (or Website > Website Tools > Custom CSS)
This code will force Burger Icon appears on Desktop.

@media screen and (min-width:768px) {
.header-burger {
    display: flex !important;
    justify-content: flex-start !important;
}
.header-nav {
    display: none;
}
.header-actions-action {
    display: none !important;
}
.header .header-announcement-bar-wrapper {
    padding-top: 0px !important;
    padding-bottom: 0px !important;
}
}

#4. Next, add this to Design > Custom CSS or Website > Website Tools > Custom CSS

@media screen and (min-width:768px) {
    /* Fix footer invisible behind page content */
footer.sections {
     z-index: 9999999 !important;
 }
/* change footer 2 sections to 100% height and 50% width */
footer.sections section:nth-child(3), footer.sections section:nth-child(4) {
    width: 50%;
    height: 100vh;
    position: fixed;
    z-index: 9999;
    left: 0;
}
footer.sections section:nth-child(3) {
    left: 0;
}
/* move footer section 4 to right 50% */
footer.sections section:nth-child(4) {
    left: 50%;
    right: 0;
}
/* disable scroll when burger menu is open */
.header-burger--open body {
    overflow: hidden;
}
/* effect on 2 sections when click burger menu */
  body footer.sections section:nth-child(3), body footer.sections section:nth-child(4) {
    transition: transform 1.2s ease;
      top: 50px !important;
}
body footer.sections section:nth-child(3) {
    transform: translateY(-150%);
    transition: transform 0.75s ease;
}
body footer.sections section:nth-child(4) {
    transform: translateY(150%);
    transition: transform 0.75s ease;
}

body.header--menu-open footer.sections section:nth-child(3) {
    transform: translateY(-0%);
    transition: transform 0.75s ease;
}

body.header--menu-open footer.sections section:nth-child(4) {
    transform: translateY(0%);
    transition: transform 0.75s ease;
}
}

Note: 50px in top: 50px !important; is space between 2 sections with bottom of header. You can adjust this value.

#5. Extra
If you want to add Dropdown Menu, you can use Accordion Block and use this CSS to remove border, background around accordion items

header#header .accordion-divider {
    display: none !important;
}
header#header .sqs-block-accordion .accordion-item__click-target {
    padding-top: 10px !important;
    padding-bottom: 10px !important;
}

Done. If you have any other questions, just comment below.

Is it possible to add the hamburger menu alongside the regular menu? Example. I definitely want to keep my cart icon in my standard header.

I will work on this more tomorrow, but here is my website in case it is helpful.

To make menu appears, you can remove this red line

to make icon appear, remove this red line