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                %h1 Underline heading
  The element has a
  %span display: block

%h1.custom With align center
  Add styling
  %span display: table
  %span margin: auto
  for align center.



  見出し要素に対してテキストの幅に合わせた下線と中央寄せのスタイルを付ける | deadwood
h1 {
  border-bottom: 1px solid #000;

h1.custom {
  display: table;
  margin: auto;

/* base styleing */
span {
  background-color: #000;
  color: #fff;