Custom CSS no longer working (help)

Site URL: https://www.startupvillage.nl/

I tried to add some Custom CSS to add a hover effect to my logo. However at some point, I apparently messed up the entire Custom CSS to the point where the CSS that was already created and working (made about an outside company) no longer works. Honestly, I'm freaking out.  I didn't copy the original CSS because I'm an idiot so now I don't know why the CSS is now longer working across my site. I have removed the custom CSS that I tried to use to create the hover effect but still nothing is working. I've attached the code and any help at all would be really appreciated!!

https://static1.squarespace.com/static/5e789f950317543ce8f43447/t/5e902a8f49de1a6c63629294/1586506383842/meetings_grid.pnghttps://static1.squarespace.com/static/5e789f950317543ce8f43447/t/5e902a8f49de1a6c63629294/1586506383842/meetings_grid.pnghttps://static1.squarespace.com/static/5e789f950317543ce8f43447/t/5e90267cf9c5f208f22ab146/1586505341004/flexdesks_grid.pnghttps://static1.squarespace.com/static/5e789f950317543ce8f43447/t/5f5e902a8f49de1a6c63629294/1586506383842/meetings_grid.pnghttps://static1.squarespace.com/static/5e789f950317543ce8f43447/t/5e90267cf9c5f208f22ab146/1586505341004/flexdesks_grid.pnghttps://static1.squarespace.com/static/5e789f950317543ce8f43447/t/5e902a8f49de1a6c63629294/1586506383842/meetings_grid.png
/* --- HOME PAGE ---  */

/* --- NAVIGATION --- */
#header > div.header-announcement-bar-wrapper > div > div.header-display > div.header-title-nav-wrapper > div.header-nav > div > nav > div:nth-child(n) > a{
        display:inline-block;
        position: relative;
}

#header > div.header-announcement-bar-wrapper > div > div.header-display > div.header-title-nav-wrapper > div.header-nav > div > nav > div:nth-child(n) > a::before{
    content:'';
    position: absolute;
    width:100%;
    transform: scaleX(0);
    height:2px;
    bottom:0;
    left:0;
    background-color: #000000;
    transform-origin: bottom right;
    transition: transform 0.25s ease-out;
}

#header > div.header-announcement-bar-wrapper > div > div.header-display > div.header-title-nav-wrapper > div.header-nav > div > nav > div:nth-child(n) > a:hover::before{
    transform: scaleX(1);
    transform-origin: bottom left;
}

/* --- Work Spaces --- */
#header > div.header-announcement-bar-wrapper > div > div.header-display > div.header-title-nav-wrapper > div.header-nav > div > nav > div.header-nav-item.header-nav-item--folder > div > div:nth-child(n) > a{
    text-align: left;
    padding-top: 10px;
}

#header > div.header-announcement-bar-wrapper > div > div.header-display > div.header-title-nav-wrapper > div.header-nav > div > nav > div.header-nav-item.header-nav-item--folder > div{
    right:auto !important;
  	left:-1em !important;
}

/* --- Community tabs --- */

.tab-btn{
  font-family:"Space Mono";
  color:#F95043;
  max-width:200px;
  display: inline-block;
  padding: 12px 18px;
  font-size:1.2em;
  background:white;
  border:2px solid #F95043;
  margin:20px;
}

.tab-btn:hover{
  background-color:#F95043;
  color:white;
  transition: 0.5s;
}

.tab-btn.active{
  background:#F95043;
  color:white;
 font-family:"Space Mono"
}

.tab-section-hide{
  display:none;
}
.tab-section-show{
  display:block;
}

/* --- Font styles --- */

@import url('https://fonts.googleapis.com/css2?family=Work+Sans:wght@500&display=swap');

.sqsrte-large {
  font-family:"Work Sans", sans-serif;
  font-weight:500;
}

.sqsrte-small{
  color:#A9A9A9;
  }

/* --- Offices background red --- */

.background-right-blocks{
  width:80%;
  background-color:#F95043; 
  padding:10%;
  }

.background-right-blocks > p.sqsrte-large, .background-right-blocks, .background-right-blocks > p.sqsrte-small, .background-right-blocks-blue > p.sqsrte-large, .background-right-blocks-blue, .background-right-blocks-blue > p.sqsrte-small{
  color:white;
}

.background-right-blocks > a, #background-right-meetings > p.sqsrte-medium > a{
  text-decoration:underline;
  color:white;
}

#background-right-offices_image {
  background-image:url("https://static1.squarespace.com/static/5e789f950317543ce8f43447/t/5e8ee73ad24dde73b9f88cc9/1586423610491/02_offices_offices%401x.png");
  width:606px;
  height:188px;
  float:right;
  margin-top:8px;
}

/* --- Flexdesks background red --- */

#background-right-flexdesks-image {
  background-image:url("https://static1.squarespace.com/static/5e789f950317543ce8f43447/t/5e90267cf9c5f208f22ab146/1586505341004/flexdesks_grid.png");
  width:606px;
  height:188px;
  float:right;
  margin-top:8px;
  margin-bottom:20px;
}


/* --- Meetings background blue --- */

.background-right-blocks-blue{
  width:80%;
  background-color:#0F5B6D; 
  padding:10%;
  }

#background-right-meetings-image {
  background-image:url("https://static1.squarespace.com/static/5e789f950317543ce8f43447/t/5e902a8f49de1a6c63629294/1586506383842/meetings_grid.png");
  width:606px;
  height:188px;
  float:right;
  margin-top:8px;
  margin-bottom:20px;
}

/* --- Events background red --- */

#background-right-events-image {
  background-image:url("https://static1.squarespace.com/static/5e789f950317543ce8f43447/t/5e902c11e5b08e4c70caa11b/1586506770208/events_grid.png");
  width:606px;
  height:188px;
  float:right;
  margin-top:8px;
  margin-bottom:20px;
}

/* --- Our Story background red --- */

#background-right-ourstory-image {
  background-image:url("https://static1.squarespace.com/static/5e789f950317543ce8f43447/t/5e902cef8d142251c7baabef/1586506991815/ourstory_sciencepark_grid.png");
  width:606px;
  height:188px;
  float:right;
  margin-top:8px;
  margin-bottom:20px;
}

/* --- Calendar cursor inactive --- */

#yui_3_17_2_1_1586507539487_262 > div.summary-thumbnail-outer-container > a{
  cursor:default !important;
}

Remove Line 01

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1 minute ago, tuanphan said:

Remove Line 01

https://static1.squarespace.com/static/5e789f950317543ce8f43447/t/5e902a8f49de1a6c63629294/1586506383842/meetings_grid.pnghttps://static1.squarespace.com/static/5e789f950317543ce8f43447/t/5e902a8f49de1a6c63629294/1586506383842/meetings_grid.pnghttps://static1.squarespace.com/static/5e789f950317543ce8f43447/t/5e90267cf9c5f208f22ab146/1586505341004/flexdesks_grid.pnghttps://static1.squarespace.com/static/5e789f950317543ce8f43447/t/5f5e902a8f49de1a6c63629294/1586506383842/meetings_grid.pnghttps://static1.squarespace.com/static/5e789f950317543ce8f43447/t/5e90267cf9c5f208f22ab146/1586505341004/flexdesks_grid.pnghttps://static1.squarespace.com/static/5e789f950317543ce8f43447/t/5e902a8f49de1a6c63629294/1586506383842/meetings_grid.png

 

I did but it says "Cannot read property 'href' of undefined"

I responded in your other thread as well. What isn't working?

It seems that all of the CSS is loading properly with no errors.