* {
  margin: 0;
  padding: 0;
}

.container {
  width: 100%;
  height: 100vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
}

#img {
  width: 150px;
  height: 150px;
}

.btn {
  position: relative;
  width: 160px;
  height: 45px;
  margin: 20px;
  font-size: 1.2rem;
  font-family: "Times New Roman", Times, serif;
  font-weight: 700;
  background: linear-gradient(45deg, black, #333);
  color: white;
  border: none;
  cursor: pointer;
  overflow: hidden;
  border-radius: 8px;
}

.btn::before {
  content: "";
  position: absolute;
  top: 50%;
  left: 50%;
  width: 300%;
  height: 300%;
  background: radial-gradient(
    circle,
    rgba(255, 255, 255, 0.3) 10%,
    transparent 50%
  );
  transition: width 0.3s, height 0.3s, top 0.3s, left 0.3s;
  transform: translate(-50%, -50%);
  opacity: 0;
}

.btn:hover::before {
  width: 100%;
  height: 100%;
  opacity: 1;
}

.btn:hover {
  color: #fff;
  background: linear-gradient(45deg, #333, black);
  box-shadow: 0px 0px 15px rgba(0, 0, 0, 0.3);
}