svg-css/bars-fade.svg

<svg width="24" height="24" viewBox="0 0 24 24" xmlns="http://www.w3.org/2000/svg"><style>.spinner_GmWz{animation:spinner_Ctle .8s linear infinite;animation-delay:-.8s}.spinner_NuDr{animation-delay:-.65s}.spinner_OlQ0{animation-delay:-.5s}@keyframes spinner_Ctle{93.75%,100%{opacity:.2}}</style><rect class="spinner_GmWz" x="1" y="4" width="6" height="14"/><rect class="spinner_GmWz spinner_NuDr" x="9" y="4" width="6" height="14"/><rect class="spinner_GmWz spinner_OlQ0" x="17" y="4" width="6" height="14"/></svg>