hugo-simpleIntro/layouts/partials/utilities/wave.html

    <div
      class="wave wave1"
      style="background-image: url('{{ .Site.BaseURL }}/img/wave.png');"
    ></div>
    <div
      class="wave wave2"
      style="background-image: url('{{ .Site.BaseURL }}/img/wave.png');"
    ></div>
    <div
      class="wave wave3"
      style="background-image: url('{{ .Site.BaseURL }}/img/wave.png');"
    ></div>
    <div
      class="wave wave4"
      style="background-image: url('{{ .Site.BaseURL }}/img/wave.png');"
    ></div>