/* <length> values */
padding-block-start: 10px; /* An absolute length */
padding-block-start: 1em; /* A length relative to the text size */

/* <percentage> value */
padding-block-start: 5%; /* A padding relative to the block container's width */

/* Global values */
padding-block-start: inherit;
padding-block-start: initial;
padding-block-start: revert;
padding-block-start: revert-layer;
padding-block-start: unset;

<div>
  <p class="exampleText">Example text</p>
</div>

div {
  background-color: yellow;
  width: 120px;
  height: 120px;
}

.exampleText {
  writing-mode: vertical-lr;
  padding-block-start: 20px;
  background-color: #c8c800;
}