Fix WordPress admin styles when loading theme styles in the admin

wordpress-fix-admin-styles.scss

// Restore WordPress sidebar core styles which are broken by theme styles
.edit-post-sidebar {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen-Sans, Ubuntu, Cantarell, "Helvetica Neue", sans-serif;
  font-size: 13px;
  font-weight: unset;
  line-height: 1.4em;
  text-align: unset;

  * {
    font-family: inherit;
    font-size: inherit;
    font-weight: inherit;
    line-height: inherit;
  }

  ul,
  ol {
    list-style: none;
    margin-bottom: unset;
    margin-top: unset;
    padding: 0;
  }

  button {
    border-radius: unset;
    margin: unset;
    overflow: unset;
    text-transform: unset;
    -webkit-appearance: unset;
  }

  a {
    color: #0073aa;
    text-decoration-color: unset;

    &:active,
    &:hover {
      color: #00a0d2;
    }
  }

  .edit-post-post-link__link-post-name {
    font-weight: 600;
  }

  .editor-post-featured-image__toggle {
    line-height: 20px;
  }

  .components-color-palette__item {
    border-radius: 50%;
  }
}

// Restore WordPress post header and admin menu core styles which are broken by theme styles
.edit-post-header,
body #adminmenu {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen-Sans, Ubuntu, Cantarell, "Helvetica Neue", sans-serif;
}