<!-- https://opentutorials.org/module/2367/13464 의 수업 예제 -->
<h1>Hello world</h1>
<h1>Hello world</h1>
          h1{
              border:1px solid red;
              margin:100px;
          }
Run Pen

External CSS

This Pen doesn't use any external CSS resources.

External JavaScript

This Pen doesn't use any external JavaScript resources.