* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  color: white;
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen, Ubuntu, Cantarell, "Open Sans", "Helvetica Neue", sans-serif;
}

html, body {
  height: 100%;
  width: 100%;
}

#main {
  height: 100%;
  width: 100%;
  background-color: black;
  position: relative;
}

.elem {
  height: 150px;
  width: 100%;
  border-bottom: 2px solid white;
  display: flex;
  align-items: center;
  justify-content: flex-start;
  position: relative;
}
.elem h1 {
  font-size: 6vw;
  position: relative;
  z-index: 9;
  mix-blend-mode: difference;
}
.elem img {
  height: 150px;
  width: 150px;
  -o-object-fit: cover;
     object-fit: cover;
  -o-object-position: center;
     object-position: center;
  border-radius: 50%;
  position: absolute;
  opacity: 0;
  transition: all linear 0.3s;
}