The Html:
  <!-- // Education --
        <section id="education" class="education">
        <div class="content-wrap">
        <h2>Education</h2>

        <!-- School details: copy this whole block to add more schools. -->
        <h3>School name 2017 - present</h3>
        <p>Designation received</p>

        <!-- Add as many paragraphs as you need. -->
        <p>Summary.</p>
        <!-- End of school details. -->
        </div>
       </section>

The CSS:
        .education {
         background: linear-gradient(rgba(141, 153, 174, 0.8),
        (rgba(141, 153, 174, 0.5)),
        url("samuel-beckett-bridge.jpg") no-repeat fixed);
        background-size: cover;
        }