@wordpress/block-library/build-style/buttons/editor.css

Block library for the WordPress editor.

.wp-block-buttons > .wp-block {
  margin: 0;
}
.wp-block-buttons > .wp-block-button.wp-block-button.wp-block-button.wp-block-button.wp-block-button {
  margin: 0;
}
.wp-block-buttons > .block-list-appender {
  display: inline-flex;
  align-items: center;
}
.wp-block-buttons.is-vertical > .block-list-appender .block-list-appender__toggle {
  justify-content: flex-start;
}
.wp-block-buttons > .wp-block-button:focus {
  box-shadow: none;
}
.wp-block-buttons {
  /* stylelint-disable @stylistic/indentation -- Disable the stylelint rule, otherwise this selector is ugly! */
}
.wp-block-buttons:not(.is-content-justification-space-between,
.is-content-justification-right,
.is-content-justification-left,
.is-content-justification-center) .wp-block[data-align=center] {
  /* stylelint-enable @stylistic/indentation */
  margin-left: auto;
  margin-right: auto;
  margin-top: 0;
  width: 100%;
}
.wp-block-buttons:not(.is-content-justification-space-between,
.is-content-justification-right,
.is-content-justification-left,
.is-content-justification-center) .wp-block[data-align=center] .wp-block-button {
  margin-bottom: 0;
}

.wp-block[data-align=center] > .wp-block-buttons {
  align-items: center;
  justify-content: center;
}

.wp-block[data-align=right] > .wp-block-buttons {
  justify-content: flex-end;
}