Decrease the margin and push down content below

When the link stay closed it has a very big bottom margin. I need decrease the margin and push down content below upon the slidedown.

#menu-toggle2 {
  display: none;
}

#collapse-menu2 {
  transition: transform 0.3s;
  transform-origin: top;
}

input:not(:checked)~#collapse-menu2 {
  transform: scaleY(0);
}

.pinkdok {
  color: #FF4870;
  cursor: pointer;
}

<h4>Архив прошлых уведомлений</h4>
<input id="menu-toggle2" type="checkbox">
<label id="menu-label" for="menu-toggle2">
  <h6 class="pinkdok">Подробнее</h6>
</label>
<ul id="collapse-menu2">
  <li>Должники на 01.01.2019<br>
    <a class="pinkdok" href="https://domain.ru/wp-content/uploads/2019/02/Dolgi01012019g.xls.pdf" target="_blank" rel="noopener noreferrer">Скачать документ (.pdf)</a></li>
</ul>

Solution

When your elements aren't visible within the DOM, that doesn't mean they don't take their space. The UL element still had some height. Although this is a quick fix. This will help you forward.

For example this CSS:

opacity: 0; /* The element is invisible, but still takes space */
---
display: none; /* The element is invisible, and won't take any space */

Within your example, you used scaleY() but the element will still take it's space within the DOM.

#menu-toggle2 {
  display: none;
}

#collapse-menu2 {
  transition: transform 0.3s;
  transform-origin: top;
  height: auto;  /* added to example */
}

input:not(:checked)~#collapse-menu2 {
  transform: scaleY(0);
  height: 0; /* added to example */
}

.pinkdok {
  color: #FF4870;
  cursor: pointer;
}


/* Not question related */

p {
  margin: 0;
}

<h4>Архив прошлых уведомлений</h4>
<input id="menu-toggle2" type="checkbox">
<label id="menu-label" for="menu-toggle2">
  <h6 class="pinkdok">Подробнее</h6>
</label>
<ul id="collapse-menu2">
  <li>Должники на 01.01.2019<br>
    <a class="pinkdok" href="https://gbu-chs.ru/wp-content/uploads/2019/02/Dolgi01012019g.xls.pdf" target="_blank" rel="noopener noreferrer">Скачать документ (.pdf)</a></li>
</ul>
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