.demo_btn_container {
  display: flex;
  justify-content: center;
  align-items: center;
}

.demo_btn {
  text-decoration: none;
  border: 1px solid rgb(163, 163, 163);
  position: relative;
  overflow: hidden;
  font-size: 1.5rem;
  padding: 1rem 3rem;
  color: #6f6f6f;
  text-transform: uppercase;
  cursor: pointer;
}

.demo_btn:hover {
  box-shadow: 1px 1px 25px 10px rgba(66, 66, 66, 0.4);
}

.demo_btn:before {
  content: "";
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(
    120deg,
    transparent,
    rgba(145, 145, 145, 0.4),
    transparent
  );
  transition: all 650ms;
}

.demo_btn:hover:before {
  left: 100%;
}