admin/public/plugins/element-plus/theme-chalk/src/header.scss

@use 'mixins/mixins' as *;
@use 'mixins/var' as *;
@use 'common/var' as *;

@include b(header) {
  @include set-component-css-var('header', $header);

  padding: getCssVar('header-padding');
  box-sizing: border-box;
  flex-shrink: 0;
  height: getCssVar('header-height');
}