body {
  height: 100vh;
  overflow: hidden;
  display: grid;
  place-items: center;
}

.loader {
  width: fit-content;
  font-weight: bold;
  font-family: monospace;
  font-size: 30px;
  background: linear-gradient(
      135deg,
      #0000 calc(50% - 0.5em),
      #000 0 calc(50% + 0.5em),
      #0000 0
    )
    right/300% 100%;
  animation: loading 2s infinite;
}

.loader::before {
  content: "Loading...";
  color: #0000;
  padding: 0 5px;
  background: inherit;
  background-image: linear-gradient(
    135deg,
    #000 calc(50% - 0.5em),
    #fff 0 calc(50% + 0.5em),
    #000 0
  );
  background-clip: text;
}

@keyframes loading {
  100% {
    background-position: left;
  }
}